RISC-V Patches for the 6.4 Merge Window, Part 1

* Support for runtime detection of the Svnapot extension.
 * Support for Zicboz when clearing pages.
 * We've moved to GENERIC_ENTRY.
 * Support for !MMU on rv32 systems.
 * The linear region is now mapped via huge pages.
 * Support for building relocatable kernels.
 * Support for the hwprobe interface.
 * Various fixes and cleanups throughout the tree.
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Merge tag 'riscv-for-linus-6.4-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:

 - Support for runtime detection of the Svnapot extension

 - Support for Zicboz when clearing pages

 - We've moved to GENERIC_ENTRY

 - Support for !MMU on rv32 systems

 - The linear region is now mapped via huge pages

 - Support for building relocatable kernels

 - Support for the hwprobe interface

 - Various fixes and cleanups throughout the tree

* tag 'riscv-for-linus-6.4-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (57 commits)
  RISC-V: hwprobe: Explicity check for -1 in vdso init
  RISC-V: hwprobe: There can only be one first
  riscv: Allow to downgrade paging mode from the command line
  dt-bindings: riscv: add sv57 mmu-type
  RISC-V: hwprobe: Remove __init on probe_vendor_features()
  riscv: Use --emit-relocs in order to move .rela.dyn in init
  riscv: Check relocations at compile time
  powerpc: Move script to check relocations at compile time in scripts/
  riscv: Introduce CONFIG_RELOCATABLE
  riscv: Move .rela.dyn outside of init to avoid empty relocations
  riscv: Prepare EFI header for relocatable kernels
  riscv: Unconditionnally select KASAN_VMALLOC if KASAN
  riscv: Fix ptdump when KASAN is enabled
  riscv: Fix EFI stub usage of KASAN instrumented strcmp function
  riscv: Move DTB_EARLY_BASE_VA to the kernel address space
  riscv: Rework kasan population functions
  riscv: Split early and final KASAN population functions
  riscv: Use PUD/P4D/PGD pages for the linear mapping
  riscv: Move the linear mapping creation in its own function
  riscv: Get rid of riscv_pfn_base variable
  ...

Documentation/admin-guide/kernel-parameters.txt

@@ -3612,7 +3612,10 @@
 			emulation library even if a 387 maths coprocessor
 			is present.
 
-	no5lvl		[X86-64] Disable 5-level paging mode. Forces
+	no4lvl		[RISCV] Disable 4-level and 5-level paging modes. Forces
+			kernel to use 3-level paging instead.
+
+	no5lvl		[X86-64,RISCV] Disable 5-level paging mode. Forces
 			kernel to use 4-level paging instead.
 
 	noaliencache	[MM, NUMA, SLAB] Disables the allocation of alien

Documentation/devicetree/bindings/riscv/cpus.yaml

@@ -66,6 +66,7 @@ properties:
       - riscv,sv32
       - riscv,sv39
       - riscv,sv48
+      - riscv,sv57
       - riscv,none
 
   riscv,cbom-block-size:
@@ -73,6 +74,11 @@ properties:
     description:
       The blocksize in bytes for the Zicbom cache operations.
 
+  riscv,cboz-block-size:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description:
+      The blocksize in bytes for the Zicboz cache operations.
+
   riscv,isa:
     description:
       Identifies the specific RISC-V instruction set architecture

Documentation/riscv/hwprobe.rst

@@ -0,0 +1,86 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+RISC-V Hardware Probing Interface
+---------------------------------
+
+The RISC-V hardware probing interface is based around a single syscall, which
+is defined in <asm/hwprobe.h>::
+
+    struct riscv_hwprobe {
+        __s64 key;
+        __u64 value;
+    };
+
+    long sys_riscv_hwprobe(struct riscv_hwprobe *pairs, size_t pair_count,
+                           size_t cpu_count, cpu_set_t *cpus,
+                           unsigned int flags);
+
+The arguments are split into three groups: an array of key-value pairs, a CPU
+set, and some flags. The key-value pairs are supplied with a count. Userspace
+must prepopulate the key field for each element, and the kernel will fill in the
+value if the key is recognized. If a key is unknown to the kernel, its key field
+will be cleared to -1, and its value set to 0. The CPU set is defined by
+CPU_SET(3). For value-like keys (eg. vendor/arch/impl), the returned value will
+be only be valid if all CPUs in the given set have the same value. Otherwise -1
+will be returned. For boolean-like keys, the value returned will be a logical
+AND of the values for the specified CPUs. Usermode can supply NULL for cpus and
+0 for cpu_count as a shortcut for all online CPUs. There are currently no flags,
+this value must be zero for future compatibility.
+
+On success 0 is returned, on failure a negative error code is returned.
+
+The following keys are defined:
+
+* :c:macro:`RISCV_HWPROBE_KEY_MVENDORID`: Contains the value of ``mvendorid``,
+  as defined by the RISC-V privileged architecture specification.
+
+* :c:macro:`RISCV_HWPROBE_KEY_MARCHID`: Contains the value of ``marchid``, as
+  defined by the RISC-V privileged architecture specification.
+
+* :c:macro:`RISCV_HWPROBE_KEY_MIMPLID`: Contains the value of ``mimplid``, as
+  defined by the RISC-V privileged architecture specification.
+
+* :c:macro:`RISCV_HWPROBE_KEY_BASE_BEHAVIOR`: A bitmask containing the base
+  user-visible behavior that this kernel supports.  The following base user ABIs
+  are defined:
+
+  * :c:macro:`RISCV_HWPROBE_BASE_BEHAVIOR_IMA`: Support for rv32ima or
+    rv64ima, as defined by version 2.2 of the user ISA and version 1.10 of the
+    privileged ISA, with the following known exceptions (more exceptions may be
+    added, but only if it can be demonstrated that the user ABI is not broken):
+
+    * The :fence.i: instruction cannot be directly executed by userspace
+      programs (it may still be executed in userspace via a
+      kernel-controlled mechanism such as the vDSO).
+
+* :c:macro:`RISCV_HWPROBE_KEY_IMA_EXT_0`: A bitmask containing the extensions
+  that are compatible with the :c:macro:`RISCV_HWPROBE_BASE_BEHAVIOR_IMA`:
+  base system behavior.
+
+  * :c:macro:`RISCV_HWPROBE_IMA_FD`: The F and D extensions are supported, as
+    defined by commit cd20cee ("FMIN/FMAX now implement
+    minimumNumber/maximumNumber, not minNum/maxNum") of the RISC-V ISA manual.
+
+  * :c:macro:`RISCV_HWPROBE_IMA_C`: The C extension is supported, as defined
+    by version 2.2 of the RISC-V ISA manual.
+
+* :c:macro:`RISCV_HWPROBE_KEY_CPUPERF_0`: A bitmask that contains performance
+  information about the selected set of processors.
+
+  * :c:macro:`RISCV_HWPROBE_MISALIGNED_UNKNOWN`: The performance of misaligned
+    accesses is unknown.
+
+  * :c:macro:`RISCV_HWPROBE_MISALIGNED_EMULATED`: Misaligned accesses are
+    emulated via software, either in or below the kernel.  These accesses are
+    always extremely slow.
+
+  * :c:macro:`RISCV_HWPROBE_MISALIGNED_SLOW`: Misaligned accesses are supported
+    in hardware, but are slower than the cooresponding aligned accesses
+    sequences.
+
+  * :c:macro:`RISCV_HWPROBE_MISALIGNED_FAST`: Misaligned accesses are supported
+    in hardware and are faster than the cooresponding aligned accesses
+    sequences.
+
+  * :c:macro:`RISCV_HWPROBE_MISALIGNED_UNSUPPORTED`: Misaligned accesses are
+    not supported at all and will generate a misaligned address fault.

Documentation/riscv/index.rst

@@ -7,6 +7,7 @@ RISC-V architecture
 
     boot-image-header
     vm-layout
+    hwprobe
     patch-acceptance
     uabi
 

arch/powerpc/tools/relocs_check.sh

@@ -15,21 +15,8 @@ if [ $# -lt 3 ]; then
 	exit 1
 fi
 
-# Have Kbuild supply the path to objdump and nm so we handle cross compilation.
-objdump="$1"
-nm="$2"
-vmlinux="$3"
-
-# Remove from the bad relocations those that match an undefined weak symbol
-# which will result in an absolute relocation to 0.
-# Weak unresolved symbols are of that form in nm output:
-# "                  w _binary__btf_vmlinux_bin_end"
-undef_weak_symbols=$($nm "$vmlinux" | awk '$1 ~ /w/ { print $2 }')
-
 bad_relocs=$(
-$objdump -R "$vmlinux" |
-	# Only look at relocation lines.
-	grep -E '\<R_' |
+${srctree}/scripts/relocs_check.sh "$@" |
 	# These relocations are okay
 	# On PPC64:
 	#	R_PPC64_RELATIVE, R_PPC64_NONE
@@ -44,8 +31,7 @@ R_PPC_ADDR16_LO
 R_PPC_ADDR16_HI
 R_PPC_ADDR16_HA
 R_PPC_RELATIVE
-R_PPC_NONE' |
-	([ "$undef_weak_symbols" ] && grep -F -w -v "$undef_weak_symbols" || cat)
+R_PPC_NONE'
 )
 
 if [ -z "$bad_relocs" ]; then

arch/riscv/Kconfig

@@ -33,6 +33,7 @@ config RISCV
 	select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL
 	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
 	select ARCH_HAS_UBSAN_SANITIZE_ALL
+	select ARCH_HAS_VDSO_DATA
 	select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
 	select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
 	select ARCH_STACKWALK
@@ -44,7 +45,7 @@ config RISCV
 	select ARCH_USE_QUEUED_RWLOCKS
 	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
 	select ARCH_WANT_FRAME_POINTERS
-	select ARCH_WANT_GENERAL_HUGETLB
+	select ARCH_WANT_GENERAL_HUGETLB if !RISCV_ISA_SVNAPOT
 	select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
 	select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
 	select ARCH_WANT_LD_ORPHAN_WARN if !XIP_KERNEL
@@ -60,6 +61,7 @@ config RISCV
 	select GENERIC_ATOMIC64 if !64BIT
 	select GENERIC_CLOCKEVENTS_BROADCAST if SMP
 	select GENERIC_EARLY_IOREMAP
+	select GENERIC_ENTRY
 	select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
 	select GENERIC_IDLE_POLL_SETUP
 	select GENERIC_IOREMAP if MMU
@@ -121,6 +123,7 @@ config RISCV
 	select HAVE_SYSCALL_TRACEPOINTS
 	select IRQ_DOMAIN
 	select IRQ_FORCED_THREADING
+	select KASAN_VMALLOC if KASAN
 	select MODULES_USE_ELF_RELA if MODULES
 	select MODULE_SECTIONS if MODULES
 	select OF
@@ -181,8 +184,8 @@ config MMU
 
 config PAGE_OFFSET
 	hex
-	default 0xC0000000 if 32BIT
-	default 0x80000000 if 64BIT && !MMU
+	default 0xC0000000 if 32BIT && MMU
+	default 0x80000000 if !MMU
 	default 0xff60000000000000 if 64BIT
 
 config KASAN_SHADOW_OFFSET
@@ -249,7 +252,7 @@ config AS_HAS_INSN
 	def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero)
 
 source "arch/riscv/Kconfig.socs"
-source "arch/riscv/Kconfig.erratas"
+source "arch/riscv/Kconfig.errata"
 
 menu "Platform type"
 
@@ -283,7 +286,6 @@ config ARCH_RV32I
 	select GENERIC_LIB_ASHRDI3
 	select GENERIC_LIB_LSHRDI3
 	select GENERIC_LIB_UCMPDI2
-	select MMU
 
 config ARCH_RV64I
 	bool "RV64I"
@@ -324,6 +326,14 @@ config SMP
 
 	  If you don't know what to do here, say N.
 
+config SCHED_MC
+	bool "Multi-core scheduler support"
+	depends on SMP
+	help
+	  Multi-core scheduler support improves the CPU scheduler's decision
+	  making when dealing with multi-core CPU chips at a cost of slightly
+	  increased overhead in some places. If unsure say N here.
+
 config NR_CPUS
 	int "Maximum number of CPUs (2-512)"
 	depends on SMP
@@ -382,9 +392,9 @@ config RISCV_ALTERNATIVE
 	depends on !XIP_KERNEL
 	help
 	  This Kconfig allows the kernel to automatically patch the
-	  errata required by the execution platform at run time. The
-	  code patching is performed once in the boot stages. It means
-	  that the overhead from this mechanism is just taken once.
+	  erratum or cpufeature required by the execution platform at run
+	  time. The code patching overhead is minimal, as it's only done
+	  once at boot and once on each module load.
 
 config RISCV_ALTERNATIVE_EARLY
 	bool
@@ -402,13 +412,32 @@ config RISCV_ISA_C
 
 	  If you don't know what to do here, say Y.
 
-config RISCV_ISA_SVPBMT
-	bool "SVPBMT extension support"
+config RISCV_ISA_SVNAPOT
+	bool "Svnapot extension support for supervisor mode NAPOT pages"
 	depends on 64BIT && MMU
 	depends on RISCV_ALTERNATIVE
 	default y
 	help
-	   Adds support to dynamically detect the presence of the SVPBMT
+	  Allow kernel to detect the Svnapot ISA-extension dynamically at boot
+	  time and enable its usage.
+
+	  The Svnapot extension is used to mark contiguous PTEs as a range
+	  of contiguous virtual-to-physical translations for a naturally
+	  aligned power-of-2 (NAPOT) granularity larger than the base 4KB page
+	  size. When HUGETLBFS is also selected this option unconditionally
+	  allocates some memory for each NAPOT page size supported by the kernel.
+	  When optimizing for low memory consumption and for platforms without
+	  the Svnapot extension, it may be better to say N here.
+
+	  If you don't know what to do here, say Y.
+
+config RISCV_ISA_SVPBMT
+	bool "Svpbmt extension support for supervisor mode page-based memory types"
+	depends on 64BIT && MMU
+	depends on RISCV_ALTERNATIVE
+	default y
+	help
+	   Adds support to dynamically detect the presence of the Svpbmt
 	   ISA-extension (Supervisor-mode: page-based memory types) and
 	   enable its usage.
 
@@ -416,7 +445,7 @@ config RISCV_ISA_SVPBMT
 	   that indicate the cacheability, idempotency, and ordering
 	   properties for access to that page.
 
-	   The SVPBMT extension is only available on 64Bit cpus.
+	   The Svpbmt extension is only available on 64-bit cpus.
 
 	   If you don't know what to do here, say Y.
 
@@ -460,6 +489,19 @@ config RISCV_ISA_ZICBOM
 
 	   If you don't know what to do here, say Y.
 
+config RISCV_ISA_ZICBOZ
+	bool "Zicboz extension support for faster zeroing of memory"
+	depends on MMU
+	depends on RISCV_ALTERNATIVE
+	default y
+	help
+	   Enable the use of the Zicboz extension (cbo.zero instruction)
+	   when available.
+
+	   The Zicboz extension is used for faster zeroing of memory.
+
+	   If you don't know what to do here, say Y.
+
 config TOOLCHAIN_HAS_ZIHINTPAUSE
 	bool
 	default y
@@ -586,6 +628,20 @@ config COMPAT
 
 	  If you want to execute 32-bit userspace applications, say Y.
 
+config RELOCATABLE
+	bool "Build a relocatable kernel"
+	depends on MMU && 64BIT && !XIP_KERNEL
+	help
+          This builds a kernel as a Position Independent Executable (PIE),
+          which retains all relocation metadata required to relocate the
+          kernel binary at runtime to a different virtual address than the
+          address it was linked at.
+          Since RISCV uses the RELA relocation format, this requires a
+          relocation pass at runtime even if the kernel is loaded at the
+          same address it was linked at.
+
+          If unsure, say N.
+
 endmenu # "Kernel features"
 
 menu "Boot options"

arch/riscv/Makefile

@@ -7,9 +7,13 @@
 #
 
 OBJCOPYFLAGS    := -O binary
-LDFLAGS_vmlinux :=
+LDFLAGS_vmlinux := -z norelro
+ifeq ($(CONFIG_RELOCATABLE),y)
+	LDFLAGS_vmlinux += -shared -Bsymbolic -z notext --emit-relocs
+	KBUILD_CFLAGS += -fPIE
+endif
 ifeq ($(CONFIG_DYNAMIC_FTRACE),y)
-	LDFLAGS_vmlinux := --no-relax
+	LDFLAGS_vmlinux += --no-relax
 	KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
 ifeq ($(CONFIG_RISCV_ISA_C),y)
 	CC_FLAGS_FTRACE := -fpatchable-function-entry=4
@@ -183,3 +187,7 @@ rv64_randconfig:
 PHONY += rv32_defconfig
 rv32_defconfig:
 	$(Q)$(MAKE) -f $(srctree)/Makefile defconfig 32-bit.config
+
+PHONY += rv32_nommu_virt_defconfig
+rv32_nommu_virt_defconfig:
+	$(Q)$(MAKE) -f $(srctree)/Makefile nommu_virt_defconfig 32-bit.config

arch/riscv/Makefile.postlink

@@ -0,0 +1,49 @@
+# SPDX-License-Identifier: GPL-2.0
+# ===========================================================================
+# Post-link riscv pass
+# ===========================================================================
+#
+# Check that vmlinux relocations look sane
+
+PHONY := __archpost
+__archpost:
+
+-include include/config/auto.conf
+include $(srctree)/scripts/Kbuild.include
+
+quiet_cmd_relocs_check = CHKREL  $@
+cmd_relocs_check = 							\
+	$(CONFIG_SHELL) $(srctree)/arch/riscv/tools/relocs_check.sh "$(OBJDUMP)" "$(NM)" "$@"
+
+ifdef CONFIG_RELOCATABLE
+quiet_cmd_cp_vmlinux_relocs = CPREL   vmlinux.relocs
+cmd_cp_vmlinux_relocs = cp vmlinux vmlinux.relocs
+
+quiet_cmd_relocs_strip = STRIPREL $@
+cmd_relocs_strip = $(OBJCOPY)   --remove-section='.rel.*'       \
+                                --remove-section='.rel__*'      \
+                                --remove-section='.rela.*'      \
+                                --remove-section='.rela__*' $@
+endif
+
+# `@true` prevents complaint when there is nothing to be done
+
+vmlinux: FORCE
+	@true
+ifdef CONFIG_RELOCATABLE
+	$(call if_changed,relocs_check)
+	$(call if_changed,cp_vmlinux_relocs)
+	$(call if_changed,relocs_strip)
+endif
+
+%.ko: FORCE
+	@true
+
+clean:
+	@true
+
+PHONY += FORCE clean
+
+FORCE:
+
+.PHONY: $(PHONY)

arch/riscv/boot/Makefile

@@ -33,7 +33,14 @@ $(obj)/xipImage: vmlinux FORCE
 
 endif
 
+ifdef CONFIG_RELOCATABLE
+vmlinux.relocs: vmlinux
+	@ (! [ -f vmlinux.relocs ] && echo "vmlinux.relocs can't be found, please remove vmlinux and try again") || true
+
+$(obj)/Image: vmlinux.relocs FORCE
+else
 $(obj)/Image: vmlinux FORCE
+endif
 	$(call if_changed,objcopy)
 
 $(obj)/Image.gz: $(obj)/Image FORCE

arch/riscv/errata/sifive/errata.c

@@ -14,7 +14,7 @@
 #include <asm/errata_list.h>
 
 struct errata_info_t {
-	char name[ERRATA_STRING_LENGTH_MAX];
+	char name[32];
 	bool (*check_func)(unsigned long  arch_id, unsigned long impid);
 };
 
@@ -101,12 +101,12 @@ void __init_or_module sifive_errata_patch_func(struct alt_entry *begin,
 	for (alt = begin; alt < end; alt++) {
 		if (alt->vendor_id != SIFIVE_VENDOR_ID)
 			continue;
-		if (alt->errata_id >= ERRATA_SIFIVE_NUMBER) {
-			WARN(1, "This errata id:%d is not in kernel errata list", alt->errata_id);
+		if (alt->patch_id >= ERRATA_SIFIVE_NUMBER) {
+			WARN(1, "This errata id:%d is not in kernel errata list", alt->patch_id);
 			continue;
 		}
 
-		tmp = (1U << alt->errata_id);
+		tmp = (1U << alt->patch_id);
 		if (cpu_req_errata & tmp) {
 			mutex_lock(&text_mutex);
 			patch_text_nosync(ALT_OLD_PTR(alt), ALT_ALT_PTR(alt),

arch/riscv/errata/thead/errata.c

@@ -11,7 +11,9 @@
 #include <linux/uaccess.h>
 #include <asm/alternative.h>
 #include <asm/cacheflush.h>
+#include <asm/cpufeature.h>
 #include <asm/errata_list.h>
+#include <asm/hwprobe.h>
 #include <asm/patch.h>
 #include <asm/vendorid_list.h>
 
@@ -93,10 +95,10 @@ void __init_or_module thead_errata_patch_func(struct alt_entry *begin, struct al
 	for (alt = begin; alt < end; alt++) {
 		if (alt->vendor_id != THEAD_VENDOR_ID)
 			continue;
-		if (alt->errata_id >= ERRATA_THEAD_NUMBER)
+		if (alt->patch_id >= ERRATA_THEAD_NUMBER)
 			continue;
 
-		tmp = (1U << alt->errata_id);
+		tmp = (1U << alt->patch_id);
 		if (cpu_req_errata & tmp) {
 			oldptr = ALT_OLD_PTR(alt);
 			altptr = ALT_ALT_PTR(alt);
@@ -115,3 +117,11 @@ void __init_or_module thead_errata_patch_func(struct alt_entry *begin, struct al
 	if (stage == RISCV_ALTERNATIVES_EARLY_BOOT)
 		local_flush_icache_all();
 }
+
+void thead_feature_probe_func(unsigned int cpu,
+			      unsigned long archid,
+			      unsigned long impid)
+{
+	if ((archid == 0) && (impid == 0))
+		per_cpu(misaligned_access_speed, cpu) = RISCV_HWPROBE_MISALIGNED_FAST;
+}

arch/riscv/include/asm/alternative-macros.h

@@ -6,18 +6,18 @@
 
 #ifdef __ASSEMBLY__
 
-.macro ALT_ENTRY oldptr newptr vendor_id errata_id new_len
+.macro ALT_ENTRY oldptr newptr vendor_id patch_id new_len
 	.4byte \oldptr - .
 	.4byte \newptr - .
 	.2byte \vendor_id
 	.2byte \new_len
-	.4byte \errata_id
+	.4byte \patch_id
 .endm
 
-.macro ALT_NEW_CONTENT vendor_id, errata_id, enable = 1, new_c : vararg
+.macro ALT_NEW_CONTENT vendor_id, patch_id, enable = 1, new_c
 	.if \enable
 	.pushsection .alternative, "a"
-	ALT_ENTRY 886b, 888f, \vendor_id, \errata_id, 889f - 888f
+	ALT_ENTRY 886b, 888f, \vendor_id, \patch_id, 889f - 888f
 	.popsection
 	.subsection 1
 888 :
@@ -33,7 +33,7 @@
 	.endif
 .endm
 
-.macro ALTERNATIVE_CFG old_c, new_c, vendor_id, errata_id, enable
+.macro ALTERNATIVE_CFG old_c, new_c, vendor_id, patch_id, enable
 886 :
 	.option push
 	.option norvc
@@ -41,13 +41,13 @@
 	\old_c
 	.option pop
 887 :
-	ALT_NEW_CONTENT \vendor_id, \errata_id, \enable, \new_c
+	ALT_NEW_CONTENT \vendor_id, \patch_id, \enable, "\new_c"
 .endm
 
-.macro ALTERNATIVE_CFG_2 old_c, new_c_1, vendor_id_1, errata_id_1, enable_1,	\
-				new_c_2, vendor_id_2, errata_id_2, enable_2
-	ALTERNATIVE_CFG "\old_c", "\new_c_1", \vendor_id_1, \errata_id_1, \enable_1
-	ALT_NEW_CONTENT \vendor_id_2, \errata_id_2, \enable_2, \new_c_2
+.macro ALTERNATIVE_CFG_2 old_c, new_c_1, vendor_id_1, patch_id_1, enable_1,	\
+				new_c_2, vendor_id_2, patch_id_2, enable_2
+	ALTERNATIVE_CFG "\old_c", "\new_c_1", \vendor_id_1, \patch_id_1, \enable_1
+	ALT_NEW_CONTENT \vendor_id_2, \patch_id_2, \enable_2, "\new_c_2"
 .endm
 
 #define __ALTERNATIVE_CFG(...)		ALTERNATIVE_CFG __VA_ARGS__
@@ -58,17 +58,17 @@
 #include <asm/asm.h>
 #include <linux/stringify.h>
 
-#define ALT_ENTRY(oldptr, newptr, vendor_id, errata_id, newlen)		\
+#define ALT_ENTRY(oldptr, newptr, vendor_id, patch_id, newlen)		\
 	".4byte	((" oldptr ") - .) \n"					\
 	".4byte	((" newptr ") - .) \n"					\
 	".2byte	" vendor_id "\n"					\
 	".2byte " newlen "\n"						\
-	".4byte	" errata_id "\n"
+	".4byte	" patch_id "\n"
 
-#define ALT_NEW_CONTENT(vendor_id, errata_id, enable, new_c)		\
+#define ALT_NEW_CONTENT(vendor_id, patch_id, enable, new_c)		\
 	".if " __stringify(enable) " == 1\n"				\
 	".pushsection .alternative, \"a\"\n"				\
-	ALT_ENTRY("886b", "888f", __stringify(vendor_id), __stringify(errata_id), "889f - 888f") \
+	ALT_ENTRY("886b", "888f", __stringify(vendor_id), __stringify(patch_id), "889f - 888f") \
 	".popsection\n"							\
 	".subsection 1\n"						\
 	"888 :\n"							\
@@ -83,7 +83,7 @@
 	".previous\n"							\
 	".endif\n"
 
-#define __ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, enable)	\
+#define __ALTERNATIVE_CFG(old_c, new_c, vendor_id, patch_id, enable)	\
 	"886 :\n"							\
 	".option push\n"						\
 	".option norvc\n"						\
@@ -91,22 +91,22 @@
 	old_c "\n"							\
 	".option pop\n"							\
 	"887 :\n"							\
-	ALT_NEW_CONTENT(vendor_id, errata_id, enable, new_c)
+	ALT_NEW_CONTENT(vendor_id, patch_id, enable, new_c)
 
-#define __ALTERNATIVE_CFG_2(old_c, new_c_1, vendor_id_1, errata_id_1, enable_1,	\
-				   new_c_2, vendor_id_2, errata_id_2, enable_2)	\
-	__ALTERNATIVE_CFG(old_c, new_c_1, vendor_id_1, errata_id_1, enable_1)	\
-	ALT_NEW_CONTENT(vendor_id_2, errata_id_2, enable_2, new_c_2)
+#define __ALTERNATIVE_CFG_2(old_c, new_c_1, vendor_id_1, patch_id_1, enable_1,	\
+				   new_c_2, vendor_id_2, patch_id_2, enable_2)	\
+	__ALTERNATIVE_CFG(old_c, new_c_1, vendor_id_1, patch_id_1, enable_1)	\
+	ALT_NEW_CONTENT(vendor_id_2, patch_id_2, enable_2, new_c_2)
 
 #endif /* __ASSEMBLY__ */
 
-#define _ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, CONFIG_k)	\
-	__ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, IS_ENABLED(CONFIG_k))
+#define _ALTERNATIVE_CFG(old_c, new_c, vendor_id, patch_id, CONFIG_k)	\
+	__ALTERNATIVE_CFG(old_c, new_c, vendor_id, patch_id, IS_ENABLED(CONFIG_k))
 
-#define _ALTERNATIVE_CFG_2(old_c, new_c_1, vendor_id_1, errata_id_1, CONFIG_k_1,		\
-				  new_c_2, vendor_id_2, errata_id_2, CONFIG_k_2)		\
-	__ALTERNATIVE_CFG_2(old_c, new_c_1, vendor_id_1, errata_id_1, IS_ENABLED(CONFIG_k_1),	\
-				   new_c_2, vendor_id_2, errata_id_2, IS_ENABLED(CONFIG_k_2))
+#define _ALTERNATIVE_CFG_2(old_c, new_c_1, vendor_id_1, patch_id_1, CONFIG_k_1,		\
+				  new_c_2, vendor_id_2, patch_id_2, CONFIG_k_2)		\
+	__ALTERNATIVE_CFG_2(old_c, new_c_1, vendor_id_1, patch_id_1, IS_ENABLED(CONFIG_k_1),	\
+				   new_c_2, vendor_id_2, patch_id_2, IS_ENABLED(CONFIG_k_2))
 
 #else /* CONFIG_RISCV_ALTERNATIVE */
 #ifdef __ASSEMBLY__
@@ -137,19 +137,19 @@
 
 /*
  * Usage:
- *   ALTERNATIVE(old_content, new_content, vendor_id, errata_id, CONFIG_k)
+ *   ALTERNATIVE(old_content, new_content, vendor_id, patch_id, CONFIG_k)
  * in the assembly code. Otherwise,
- *   asm(ALTERNATIVE(old_content, new_content, vendor_id, errata_id, CONFIG_k));
+ *   asm(ALTERNATIVE(old_content, new_content, vendor_id, patch_id, CONFIG_k));
  *
  * old_content: The old content which is probably replaced with new content.
  * new_content: The new content.
  * vendor_id: The CPU vendor ID.
- * errata_id: The errata ID.
- * CONFIG_k: The Kconfig of this errata. When Kconfig is disabled, the old
+ * patch_id: The patch ID (erratum ID or cpufeature ID).
+ * CONFIG_k: The Kconfig of this patch ID. When Kconfig is disabled, the old
  *	     content will alwyas be executed.
  */
-#define ALTERNATIVE(old_content, new_content, vendor_id, errata_id, CONFIG_k) \
-	_ALTERNATIVE_CFG(old_content, new_content, vendor_id, errata_id, CONFIG_k)
+#define ALTERNATIVE(old_content, new_content, vendor_id, patch_id, CONFIG_k) \
+	_ALTERNATIVE_CFG(old_content, new_content, vendor_id, patch_id, CONFIG_k)
 
 /*
  * A vendor wants to replace an old_content, but another vendor has used
@@ -158,9 +158,9 @@
  * on the following sample code and then replace ALTERNATIVE() with
  * ALTERNATIVE_2() to append its customized content.
  */
-#define ALTERNATIVE_2(old_content, new_content_1, vendor_id_1, errata_id_1, CONFIG_k_1,		\
-				   new_content_2, vendor_id_2, errata_id_2, CONFIG_k_2)		\
-	_ALTERNATIVE_CFG_2(old_content, new_content_1, vendor_id_1, errata_id_1, CONFIG_k_1,	\
-					new_content_2, vendor_id_2, errata_id_2, CONFIG_k_2)
+#define ALTERNATIVE_2(old_content, new_content_1, vendor_id_1, patch_id_1, CONFIG_k_1,		\
+				   new_content_2, vendor_id_2, patch_id_2, CONFIG_k_2)		\
+	_ALTERNATIVE_CFG_2(old_content, new_content_1, vendor_id_1, patch_id_1, CONFIG_k_1,	\
+					new_content_2, vendor_id_2, patch_id_2, CONFIG_k_2)
 
 #endif

arch/riscv/include/asm/alternative.h

@@ -6,8 +6,6 @@
 #ifndef __ASM_ALTERNATIVE_H
 #define __ASM_ALTERNATIVE_H
 
-#define ERRATA_STRING_LENGTH_MAX 32
-
 #include <asm/alternative-macros.h>
 
 #ifndef __ASSEMBLY__
@@ -15,10 +13,14 @@
 #ifdef CONFIG_RISCV_ALTERNATIVE
 
 #include <linux/init.h>
+#include <linux/kernel.h>
 #include <linux/types.h>
 #include <linux/stddef.h>
 #include <asm/hwcap.h>
 
+#define PATCH_ID_CPUFEATURE_ID(p)		lower_16_bits(p)
+#define PATCH_ID_CPUFEATURE_VALUE(p)		upper_16_bits(p)
+
 #define RISCV_ALTERNATIVES_BOOT		0 /* alternatives applied during regular boot */
 #define RISCV_ALTERNATIVES_MODULE	1 /* alternatives applied during module-init */
 #define RISCV_ALTERNATIVES_EARLY_BOOT	2 /* alternatives applied before mmu start */
@@ -28,6 +30,7 @@
 #define ALT_OLD_PTR(a)			__ALT_PTR(a, old_offset)
 #define ALT_ALT_PTR(a)			__ALT_PTR(a, alt_offset)
 
+void probe_vendor_features(unsigned int cpu);
 void __init apply_boot_alternatives(void);
 void __init apply_early_boot_alternatives(void);
 void apply_module_alternatives(void *start, size_t length);
@@ -38,14 +41,9 @@ void riscv_alternative_fix_offsets(void *alt_ptr, unsigned int len,
 struct alt_entry {
 	s32 old_offset;		/* offset relative to original instruction or data  */
 	s32 alt_offset;		/* offset relative to replacement instruction or data */
-	u16 vendor_id;		/* cpu vendor id */
+	u16 vendor_id;		/* CPU vendor ID */
 	u16 alt_len;		/* The replacement size */
-	u32 errata_id;		/* The errata id */
-};
-
-struct errata_checkfunc_id {
-	unsigned long vendor_id;
-	bool (*func)(struct alt_entry *alt);
+	u32 patch_id;		/* The patch ID (erratum ID or cpufeature ID) */
 };
 
 void sifive_errata_patch_func(struct alt_entry *begin, struct alt_entry *end,
@@ -55,11 +53,15 @@ void thead_errata_patch_func(struct alt_entry *begin, struct alt_entry *end,
 			     unsigned long archid, unsigned long impid,
 			     unsigned int stage);
 
+void thead_feature_probe_func(unsigned int cpu, unsigned long archid,
+			      unsigned long impid);
+
 void riscv_cpufeature_patch_func(struct alt_entry *begin, struct alt_entry *end,
 				 unsigned int stage);
 
 #else /* CONFIG_RISCV_ALTERNATIVE */
 
+static inline void probe_vendor_features(unsigned int cpu) { }
 static inline void apply_boot_alternatives(void) { }
 static inline void apply_early_boot_alternatives(void) { }
 static inline void apply_module_alternatives(void *start, size_t length) { }

arch/riscv/include/asm/asm-prototypes.h

@@ -27,5 +27,7 @@ DECLARE_DO_ERROR_INFO(do_trap_break);
 
 asmlinkage unsigned long get_overflow_stack(void);
 asmlinkage void handle_bad_stack(struct pt_regs *regs);
+asmlinkage void do_page_fault(struct pt_regs *regs);
+asmlinkage void do_irq(struct pt_regs *regs);
 
 #endif /* _ASM_RISCV_PROTOTYPES_H */

arch/riscv/include/asm/asm.h

@@ -69,6 +69,7 @@
 #endif
 
 #ifdef __ASSEMBLY__
+#include <asm/asm-offsets.h>
 
 /* Common assembly source macros */
 
@@ -81,6 +82,66 @@
 	.endr
 .endm
 
+	/* save all GPs except x1 ~ x5 */
+	.macro save_from_x6_to_x31
+	REG_S x6,  PT_T1(sp)
+	REG_S x7,  PT_T2(sp)
+	REG_S x8,  PT_S0(sp)
+	REG_S x9,  PT_S1(sp)
+	REG_S x10, PT_A0(sp)
+	REG_S x11, PT_A1(sp)
+	REG_S x12, PT_A2(sp)
+	REG_S x13, PT_A3(sp)
+	REG_S x14, PT_A4(sp)
+	REG_S x15, PT_A5(sp)
+	REG_S x16, PT_A6(sp)
+	REG_S x17, PT_A7(sp)
+	REG_S x18, PT_S2(sp)
+	REG_S x19, PT_S3(sp)
+	REG_S x20, PT_S4(sp)
+	REG_S x21, PT_S5(sp)
+	REG_S x22, PT_S6(sp)
+	REG_S x23, PT_S7(sp)
+	REG_S x24, PT_S8(sp)
+	REG_S x25, PT_S9(sp)
+	REG_S x26, PT_S10(sp)
+	REG_S x27, PT_S11(sp)
+	REG_S x28, PT_T3(sp)
+	REG_S x29, PT_T4(sp)
+	REG_S x30, PT_T5(sp)
+	REG_S x31, PT_T6(sp)
+	.endm
+
+	/* restore all GPs except x1 ~ x5 */
+	.macro restore_from_x6_to_x31
+	REG_L x6,  PT_T1(sp)
+	REG_L x7,  PT_T2(sp)
+	REG_L x8,  PT_S0(sp)
+	REG_L x9,  PT_S1(sp)
+	REG_L x10, PT_A0(sp)
+	REG_L x11, PT_A1(sp)
+	REG_L x12, PT_A2(sp)
+	REG_L x13, PT_A3(sp)
+	REG_L x14, PT_A4(sp)
+	REG_L x15, PT_A5(sp)
+	REG_L x16, PT_A6(sp)
+	REG_L x17, PT_A7(sp)
+	REG_L x18, PT_S2(sp)
+	REG_L x19, PT_S3(sp)
+	REG_L x20, PT_S4(sp)
+	REG_L x21, PT_S5(sp)
+	REG_L x22, PT_S6(sp)
+	REG_L x23, PT_S7(sp)
+	REG_L x24, PT_S8(sp)
+	REG_L x25, PT_S9(sp)
+	REG_L x26, PT_S10(sp)
+	REG_L x27, PT_S11(sp)
+	REG_L x28, PT_T3(sp)
+	REG_L x29, PT_T4(sp)
+	REG_L x30, PT_T5(sp)
+	REG_L x31, PT_T6(sp)
+	.endm
+
 #endif /* __ASSEMBLY__ */
 
 #endif /* _ASM_RISCV_ASM_H */

arch/riscv/include/asm/cacheflush.h

@@ -50,7 +50,8 @@ void flush_icache_mm(struct mm_struct *mm, bool local);
 #endif /* CONFIG_SMP */
 
 extern unsigned int riscv_cbom_block_size;
-void riscv_init_cbom_blocksize(void);
+extern unsigned int riscv_cboz_block_size;
+void riscv_init_cbo_blocksizes(void);
 
 #ifdef CONFIG_RISCV_DMA_NONCOHERENT
 void riscv_noncoherent_supported(void);

arch/riscv/include/asm/cpufeature.h

@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright 2022-2023 Rivos, Inc
+ */
+
+#ifndef _ASM_CPUFEATURE_H
+#define _ASM_CPUFEATURE_H
+
+/*
+ * These are probed via a device_initcall(), via either the SBI or directly
+ * from the corresponding CSRs.
+ */
+struct riscv_cpuinfo {
+	unsigned long mvendorid;
+	unsigned long marchid;
+	unsigned long mimpid;
+};
+
+DECLARE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);
+
+DECLARE_PER_CPU(long, misaligned_access_speed);
+
+#endif

arch/riscv/include/asm/csr.h

@@ -40,7 +40,6 @@
 #define SR_UXL		_AC(0x300000000, UL) /* XLEN mask for U-mode */
 #define SR_UXL_32	_AC(0x100000000, UL) /* XLEN = 32 for U-mode */
 #define SR_UXL_64	_AC(0x200000000, UL) /* XLEN = 64 for U-mode */
-#define SR_UXL_SHIFT	32
 #endif
 
 /* SATP flags */

arch/riscv/include/asm/entry-common.h

@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _ASM_RISCV_ENTRY_COMMON_H
+#define _ASM_RISCV_ENTRY_COMMON_H
+
+#include <asm/stacktrace.h>
+
+void handle_page_fault(struct pt_regs *regs);
+void handle_break(struct pt_regs *regs);
+
+#endif /* _ASM_RISCV_ENTRY_COMMON_H */

arch/riscv/include/asm/hugetlb.h

@@ -2,7 +2,6 @@
 #ifndef _ASM_RISCV_HUGETLB_H
 #define _ASM_RISCV_HUGETLB_H
 
-#include <asm-generic/hugetlb.h>
 #include <asm/page.h>
 
 static inline void arch_clear_hugepage_flags(struct page *page)
@@ -11,4 +10,37 @@ static inline void arch_clear_hugepage_flags(struct page *page)
 }
 #define arch_clear_hugepage_flags arch_clear_hugepage_flags
 
+#ifdef CONFIG_RISCV_ISA_SVNAPOT
+#define __HAVE_ARCH_HUGE_PTE_CLEAR
+void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
+		    pte_t *ptep, unsigned long sz);
+
+#define __HAVE_ARCH_HUGE_SET_HUGE_PTE_AT
+void set_huge_pte_at(struct mm_struct *mm,
+		     unsigned long addr, pte_t *ptep, pte_t pte);
+
+#define __HAVE_ARCH_HUGE_PTEP_GET_AND_CLEAR
+pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
+			      unsigned long addr, pte_t *ptep);
+
+#define __HAVE_ARCH_HUGE_PTEP_CLEAR_FLUSH
+pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
+			    unsigned long addr, pte_t *ptep);
+
+#define __HAVE_ARCH_HUGE_PTEP_SET_WRPROTECT
+void huge_ptep_set_wrprotect(struct mm_struct *mm,
+			     unsigned long addr, pte_t *ptep);
+
+#define __HAVE_ARCH_HUGE_PTEP_SET_ACCESS_FLAGS
+int huge_ptep_set_access_flags(struct vm_area_struct *vma,
+			       unsigned long addr, pte_t *ptep,
+			       pte_t pte, int dirty);
+
+pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, vm_flags_t flags);
+#define arch_make_huge_pte arch_make_huge_pte
+
+#endif /*CONFIG_RISCV_ISA_SVNAPOT*/
+
+#include <asm-generic/hugetlb.h>
+
 #endif /* _ASM_RISCV_HUGETLB_H */

arch/riscv/include/asm/hwcap.h

@@ -42,6 +42,8 @@
 #define RISCV_ISA_EXT_ZBB		30
 #define RISCV_ISA_EXT_ZICBOM		31
 #define RISCV_ISA_EXT_ZIHINTPAUSE	32
+#define RISCV_ISA_EXT_SVNAPOT		33
+#define RISCV_ISA_EXT_ZICBOZ		34
 
 #define RISCV_ISA_EXT_MAX		64
 #define RISCV_ISA_EXT_NAME_LEN_MAX	32

arch/riscv/include/asm/hwprobe.h

@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright 2023 Rivos, Inc
+ */
+
+#ifndef _ASM_HWPROBE_H
+#define _ASM_HWPROBE_H
+
+#include <uapi/asm/hwprobe.h>
+
+#define RISCV_HWPROBE_MAX_KEY 5
+
+#endif

arch/riscv/include/asm/insn-def.h

@@ -192,4 +192,8 @@
 	INSN_I(OPCODE_MISC_MEM, FUNC3(2), __RD(0),		\
 	       RS1(base), SIMM12(2))
 
+#define CBO_zero(base)						\
+	INSN_I(OPCODE_MISC_MEM, FUNC3(2), __RD(0),		\
+	       RS1(base), SIMM12(4))
+
 #endif /* __ASM_INSN_DEF_H */

arch/riscv/include/asm/page.h

@@ -16,11 +16,6 @@
 #define PAGE_SIZE	(_AC(1, UL) << PAGE_SHIFT)
 #define PAGE_MASK	(~(PAGE_SIZE - 1))
 
-#ifdef CONFIG_64BIT
-#define HUGE_MAX_HSTATE		2
-#else
-#define HUGE_MAX_HSTATE		1
-#endif
 #define HPAGE_SHIFT		PMD_SHIFT
 #define HPAGE_SIZE		(_AC(1, UL) << HPAGE_SHIFT)
 #define HPAGE_MASK              (~(HPAGE_SIZE - 1))
@@ -49,10 +44,14 @@
 
 #ifndef __ASSEMBLY__
 
+#ifdef CONFIG_RISCV_ISA_ZICBOZ
+void clear_page(void *page);
+#else
 #define clear_page(pgaddr)			memset((pgaddr), 0, PAGE_SIZE)
+#endif
 #define copy_page(to, from)			memcpy((to), (from), PAGE_SIZE)
 
-#define clear_user_page(pgaddr, vaddr, page)	memset((pgaddr), 0, PAGE_SIZE)
+#define clear_user_page(pgaddr, vaddr, page)	clear_page(pgaddr)
 #define copy_user_page(vto, vfrom, vaddr, topg) \
 			memcpy((vto), (vfrom), PAGE_SIZE)
 
@@ -90,9 +89,16 @@ typedef struct page *pgtable_t;
 #define PTE_FMT "%08lx"
 #endif
 
+#ifdef CONFIG_64BIT
+/*
+ * We override this value as its generic definition uses __pa too early in
+ * the boot process (before kernel_map.va_pa_offset is set).
+ */
+#define MIN_MEMBLOCK_ADDR      0
+#endif
+
 #ifdef CONFIG_MMU
-extern unsigned long riscv_pfn_base;
-#define ARCH_PFN_OFFSET		(riscv_pfn_base)
+#define ARCH_PFN_OFFSET		(PFN_DOWN((unsigned long)phys_ram_base))
 #else
 #define ARCH_PFN_OFFSET		(PAGE_OFFSET >> PAGE_SHIFT)
 #endif /* CONFIG_MMU */
@@ -122,7 +128,11 @@ extern phys_addr_t phys_ram_base;
 #define is_linear_mapping(x)	\
 	((x) >= PAGE_OFFSET && (!IS_ENABLED(CONFIG_64BIT) || (x) < PAGE_OFFSET + KERN_VIRT_SIZE))
 
+#ifndef CONFIG_DEBUG_VIRTUAL
 #define linear_mapping_pa_to_va(x)	((void *)((unsigned long)(x) + kernel_map.va_pa_offset))
+#else
+void *linear_mapping_pa_to_va(unsigned long x);
+#endif
 #define kernel_mapping_pa_to_va(y)	({					\
 	unsigned long _y = (unsigned long)(y);					\
 	(IS_ENABLED(CONFIG_XIP_KERNEL) && _y < phys_ram_base) ?			\
@@ -131,7 +141,11 @@ extern phys_addr_t phys_ram_base;
 	})
 #define __pa_to_va_nodebug(x)		linear_mapping_pa_to_va(x)
 
+#ifndef CONFIG_DEBUG_VIRTUAL
 #define linear_mapping_va_to_pa(x)	((unsigned long)(x) - kernel_map.va_pa_offset)
+#else
+phys_addr_t linear_mapping_va_to_pa(unsigned long x);
+#endif
 #define kernel_mapping_va_to_pa(y) ({						\
 	unsigned long _y = (unsigned long)(y);					\
 	(IS_ENABLED(CONFIG_XIP_KERNEL) && _y < kernel_map.virt_addr + XIP_OFFSET) ? \

arch/riscv/include/asm/pgtable-64.h

@@ -78,6 +78,40 @@ typedef struct {
  */
 #define _PAGE_PFN_MASK  GENMASK(53, 10)
 
+/*
+ * [63] Svnapot definitions:
+ * 0 Svnapot disabled
+ * 1 Svnapot enabled
+ */
+#define _PAGE_NAPOT_SHIFT	63
+#define _PAGE_NAPOT		BIT(_PAGE_NAPOT_SHIFT)
+/*
+ * Only 64KB (order 4) napot ptes supported.
+ */
+#define NAPOT_CONT_ORDER_BASE 4
+enum napot_cont_order {
+	NAPOT_CONT64KB_ORDER = NAPOT_CONT_ORDER_BASE,
+	NAPOT_ORDER_MAX,
+};
+
+#define for_each_napot_order(order)						\
+	for (order = NAPOT_CONT_ORDER_BASE; order < NAPOT_ORDER_MAX; order++)
+#define for_each_napot_order_rev(order)						\
+	for (order = NAPOT_ORDER_MAX - 1;					\
+	     order >= NAPOT_CONT_ORDER_BASE; order--)
+#define napot_cont_order(val)	(__builtin_ctzl((val.pte >> _PAGE_PFN_SHIFT) << 1))
+
+#define napot_cont_shift(order)	((order) + PAGE_SHIFT)
+#define napot_cont_size(order)	BIT(napot_cont_shift(order))
+#define napot_cont_mask(order)	(~(napot_cont_size(order) - 1UL))
+#define napot_pte_num(order)	BIT(order)
+
+#ifdef CONFIG_RISCV_ISA_SVNAPOT
+#define HUGE_MAX_HSTATE		(2 + (NAPOT_ORDER_MAX - NAPOT_CONT_ORDER_BASE))
+#else
+#define HUGE_MAX_HSTATE		2
+#endif
+
 /*
  * [62:61] Svpbmt Memory Type definitions:
  *

arch/riscv/include/asm/pgtable.h

@@ -268,10 +268,47 @@ static inline pte_t pud_pte(pud_t pud)
 	return __pte(pud_val(pud));
 }
 
+#ifdef CONFIG_RISCV_ISA_SVNAPOT
+
+static __always_inline bool has_svnapot(void)
+{
+	return riscv_has_extension_likely(RISCV_ISA_EXT_SVNAPOT);
+}
+
+static inline unsigned long pte_napot(pte_t pte)
+{
+	return pte_val(pte) & _PAGE_NAPOT;
+}
+
+static inline pte_t pte_mknapot(pte_t pte, unsigned int order)
+{
+	int pos = order - 1 + _PAGE_PFN_SHIFT;
+	unsigned long napot_bit = BIT(pos);
+	unsigned long napot_mask = ~GENMASK(pos, _PAGE_PFN_SHIFT);
+
+	return __pte((pte_val(pte) & napot_mask) | napot_bit | _PAGE_NAPOT);
+}
+
+#else
+
+static __always_inline bool has_svnapot(void) { return false; }
+
+static inline unsigned long pte_napot(pte_t pte)
+{
+	return 0;
+}
+
+#endif /* CONFIG_RISCV_ISA_SVNAPOT */
+
 /* Yields the page frame number (PFN) of a page table entry */
 static inline unsigned long pte_pfn(pte_t pte)
 {
-	return __page_val_to_pfn(pte_val(pte));
+	unsigned long res  = __page_val_to_pfn(pte_val(pte));
+
+	if (has_svnapot() && pte_napot(pte))
+		res = res & (res - 1UL);
+
+	return res;
 }
 
 #define pte_page(x)     pfn_to_page(pte_pfn(x))

arch/riscv/include/asm/ptrace.h

@@ -53,6 +53,9 @@ struct pt_regs {
 	unsigned long orig_a0;
 };
 
+#define PTRACE_SYSEMU			0x1f
+#define PTRACE_SYSEMU_SINGLESTEP	0x20
+
 #ifdef CONFIG_64BIT
 #define REG_FMT "%016lx"
 #else
@@ -121,8 +124,6 @@ extern unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
 
 void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
 			   unsigned long frame_pointer);
-int do_syscall_trace_enter(struct pt_regs *regs);
-void do_syscall_trace_exit(struct pt_regs *regs);
 
 /**
  * regs_get_register() - get register value from its offset
@@ -172,6 +173,11 @@ static inline unsigned long regs_get_kernel_argument(struct pt_regs *regs,
 	return 0;
 }
 
+static inline int regs_irqs_disabled(struct pt_regs *regs)
+{
+	return !(regs->status & SR_PIE);
+}
+
 #endif /* __ASSEMBLY__ */
 
 #endif /* _ASM_RISCV_PTRACE_H */

arch/riscv/include/asm/set_memory.h

@@ -56,4 +56,7 @@ bool kernel_page_present(struct page *page);
 #define SECTION_ALIGN L1_CACHE_BYTES
 #endif /* CONFIG_STRICT_KERNEL_RWX */
 
+#define PECOFF_SECTION_ALIGNMENT        0x1000
+#define PECOFF_FILE_ALIGNMENT           0x200
+
 #endif /* _ASM_RISCV_SET_MEMORY_H */

arch/riscv/include/asm/stacktrace.h

@@ -16,4 +16,9 @@ extern void notrace walk_stackframe(struct task_struct *task, struct pt_regs *re
 extern void dump_backtrace(struct pt_regs *regs, struct task_struct *task,
 			   const char *loglvl);
 
+static inline bool on_thread_stack(void)
+{
+	return !(((unsigned long)(current->stack) ^ current_stack_pointer) & ~(THREAD_SIZE - 1));
+}
+
 #endif /* _ASM_RISCV_STACKTRACE_H */

arch/riscv/include/asm/syscall.h

@@ -10,6 +10,7 @@
 #ifndef _ASM_RISCV_SYSCALL_H
 #define _ASM_RISCV_SYSCALL_H
 
+#include <asm/hwprobe.h>
 #include <uapi/linux/audit.h>
 #include <linux/sched.h>
 #include <linux/err.h>
@@ -74,5 +75,29 @@ static inline int syscall_get_arch(struct task_struct *task)
 #endif
 }
 
+typedef long (*syscall_t)(ulong, ulong, ulong, ulong, ulong, ulong, ulong);
+static inline void syscall_handler(struct pt_regs *regs, ulong syscall)
+{
+	syscall_t fn;
+
+#ifdef CONFIG_COMPAT
+	if ((regs->status & SR_UXL) == SR_UXL_32)
+		fn = compat_sys_call_table[syscall];
+	else
+#endif
+		fn = sys_call_table[syscall];
+
+	regs->a0 = fn(regs->orig_a0, regs->a1, regs->a2,
+		      regs->a3, regs->a4, regs->a5, regs->a6);
+}
+
+static inline bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs)
+{
+	return false;
+}
+
 asmlinkage long sys_riscv_flush_icache(uintptr_t, uintptr_t, uintptr_t);
+
+asmlinkage long sys_riscv_hwprobe(struct riscv_hwprobe *, size_t, size_t,
+				  unsigned long *, unsigned int);
 #endif	/* _ASM_RISCV_SYSCALL_H */

arch/riscv/include/asm/thread_info.h

@@ -67,6 +67,7 @@ struct thread_info {
 	long			kernel_sp;	/* Kernel stack pointer */
 	long			user_sp;	/* User stack pointer */
 	int			cpu;
+	unsigned long		syscall_work;	/* SYSCALL_WORK_ flags */
 };
 
 /*
@@ -89,26 +90,18 @@ struct thread_info {
  * - pending work-to-be-done flags are in lowest half-word
  * - other flags in upper half-word(s)
  */
-#define TIF_SYSCALL_TRACE	0	/* syscall trace active */
 #define TIF_NOTIFY_RESUME	1	/* callback before returning to user */
 #define TIF_SIGPENDING		2	/* signal pending */
 #define TIF_NEED_RESCHED	3	/* rescheduling necessary */
 #define TIF_RESTORE_SIGMASK	4	/* restore signal mask in do_signal() */
 #define TIF_MEMDIE		5	/* is terminating due to OOM killer */
-#define TIF_SYSCALL_TRACEPOINT  6       /* syscall tracepoint instrumentation */
-#define TIF_SYSCALL_AUDIT	7	/* syscall auditing */
-#define TIF_SECCOMP		8	/* syscall secure computing */
 #define TIF_NOTIFY_SIGNAL	9	/* signal notifications exist */
 #define TIF_UPROBE		10	/* uprobe breakpoint or singlestep */
 #define TIF_32BIT		11	/* compat-mode 32bit process */
 
-#define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
 #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
-#define _TIF_SYSCALL_TRACEPOINT	(1 << TIF_SYSCALL_TRACEPOINT)
-#define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
-#define _TIF_SECCOMP		(1 << TIF_SECCOMP)
 #define _TIF_NOTIFY_SIGNAL	(1 << TIF_NOTIFY_SIGNAL)
 #define _TIF_UPROBE		(1 << TIF_UPROBE)
 
@@ -116,8 +109,4 @@ struct thread_info {
 	(_TIF_NOTIFY_RESUME | _TIF_SIGPENDING | _TIF_NEED_RESCHED | \
 	 _TIF_NOTIFY_SIGNAL | _TIF_UPROBE)
 
-#define _TIF_SYSCALL_WORK \
-	(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_SYSCALL_AUDIT | \
-	 _TIF_SECCOMP)
-
 #endif /* _ASM_RISCV_THREAD_INFO_H */

arch/riscv/include/asm/topology.h

@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_RISCV_TOPOLOGY_H
+#define _ASM_RISCV_TOPOLOGY_H
+
+#include <linux/arch_topology.h>
+
+/* Replace task scheduler's default frequency-invariant accounting */
+#define arch_scale_freq_tick		topology_scale_freq_tick
+#define arch_set_freq_scale		topology_set_freq_scale
+#define arch_scale_freq_capacity	topology_get_freq_scale
+#define arch_scale_freq_invariant	topology_scale_freq_invariant
+
+/* Replace task scheduler's default cpu-invariant accounting */
+#define arch_scale_cpu_capacity	topology_get_cpu_scale
+
+/* Enable topology flag updates */
+#define arch_update_cpu_topology	topology_update_cpu_topology
+
+#include <asm-generic/topology.h>
+
+#endif /* _ASM_RISCV_TOPOLOGY_H */

arch/riscv/include/asm/vdso/data.h

@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __RISCV_ASM_VDSO_DATA_H
+#define __RISCV_ASM_VDSO_DATA_H
+
+#include <linux/types.h>
+#include <vdso/datapage.h>
+#include <asm/hwprobe.h>
+
+struct arch_vdso_data {
+	/* Stash static answers to the hwprobe queries when all CPUs are selected. */
+	__u64 all_cpu_hwprobe_values[RISCV_HWPROBE_MAX_KEY + 1];
+
+	/* Boolean indicating all CPUs have the same static hwprobe values. */
+	__u8 homogeneous_cpus;
+};
+
+#endif /* __RISCV_ASM_VDSO_DATA_H */

arch/riscv/include/asm/vdso/gettimeofday.h

@@ -9,6 +9,12 @@
 #include <asm/csr.h>
 #include <uapi/linux/time.h>
 
+/*
+ * 32-bit land is lacking generic time vsyscalls as well as the legacy 32-bit
+ * time syscalls like gettimeofday. Skip these definitions since on 32-bit.
+ */
+#ifdef CONFIG_GENERIC_TIME_VSYSCALL
+
 #define VDSO_HAS_CLOCK_GETRES	1
 
 static __always_inline
@@ -60,6 +66,8 @@ int clock_getres_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
 	return ret;
 }
 
+#endif /* CONFIG_GENERIC_TIME_VSYSCALL */
+
 static __always_inline u64 __arch_get_hw_counter(s32 clock_mode,
 						 const struct vdso_data *vd)
 {

arch/riscv/include/asm/vmalloc.h

@@ -17,6 +17,65 @@ static inline bool arch_vmap_pmd_supported(pgprot_t prot)
 	return true;
 }
 
-#endif
+#ifdef CONFIG_RISCV_ISA_SVNAPOT
+#include <linux/pgtable.h>
 
+#define arch_vmap_pte_range_map_size arch_vmap_pte_range_map_size
+static inline unsigned long arch_vmap_pte_range_map_size(unsigned long addr, unsigned long end,
+							 u64 pfn, unsigned int max_page_shift)
+{
+	unsigned long map_size = PAGE_SIZE;
+	unsigned long size, order;
+
+	if (!has_svnapot())
+		return map_size;
+
+	for_each_napot_order_rev(order) {
+		if (napot_cont_shift(order) > max_page_shift)
+			continue;
+
+		size = napot_cont_size(order);
+		if (end - addr < size)
+			continue;
+
+		if (!IS_ALIGNED(addr, size))
+			continue;
+
+		if (!IS_ALIGNED(PFN_PHYS(pfn), size))
+			continue;
+
+		map_size = size;
+		break;
+	}
+
+	return map_size;
+}
+
+#define arch_vmap_pte_supported_shift arch_vmap_pte_supported_shift
+static inline int arch_vmap_pte_supported_shift(unsigned long size)
+{
+	int shift = PAGE_SHIFT;
+	unsigned long order;
+
+	if (!has_svnapot())
+		return shift;
+
+	WARN_ON_ONCE(size >= PMD_SIZE);
+
+	for_each_napot_order_rev(order) {
+		if (napot_cont_size(order) > size)
+			continue;
+
+		if (!IS_ALIGNED(size, napot_cont_size(order)))
+			continue;
+
+		shift = napot_cont_shift(order);
+		break;
+	}
+
+	return shift;
+}
+
+#endif /* CONFIG_RISCV_ISA_SVNAPOT */
+#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
 #endif /* _ASM_RISCV_VMALLOC_H */

arch/riscv/include/uapi/asm/hwprobe.h

@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright 2023 Rivos, Inc
+ */
+
+#ifndef _UAPI_ASM_HWPROBE_H
+#define _UAPI_ASM_HWPROBE_H
+
+#include <linux/types.h>
+
+/*
+ * Interface for probing hardware capabilities from userspace, see
+ * Documentation/riscv/hwprobe.rst for more information.
+ */
+struct riscv_hwprobe {
+	__s64 key;
+	__u64 value;
+};
+
+#define RISCV_HWPROBE_KEY_MVENDORID	0
+#define RISCV_HWPROBE_KEY_MARCHID	1
+#define RISCV_HWPROBE_KEY_MIMPID	2
+#define RISCV_HWPROBE_KEY_BASE_BEHAVIOR	3
+#define		RISCV_HWPROBE_BASE_BEHAVIOR_IMA	(1 << 0)
+#define RISCV_HWPROBE_KEY_IMA_EXT_0	4
+#define		RISCV_HWPROBE_IMA_FD		(1 << 0)
+#define		RISCV_HWPROBE_IMA_C		(1 << 1)
+#define RISCV_HWPROBE_KEY_CPUPERF_0	5
+#define		RISCV_HWPROBE_MISALIGNED_UNKNOWN	(0 << 0)
+#define		RISCV_HWPROBE_MISALIGNED_EMULATED	(1 << 0)
+#define		RISCV_HWPROBE_MISALIGNED_SLOW		(2 << 0)
+#define		RISCV_HWPROBE_MISALIGNED_FAST		(3 << 0)
+#define		RISCV_HWPROBE_MISALIGNED_UNSUPPORTED	(4 << 0)
+#define		RISCV_HWPROBE_MISALIGNED_MASK		(7 << 0)
+/* Increase RISCV_HWPROBE_MAX_KEY when adding items. */
+
+#endif

arch/riscv/include/uapi/asm/kvm.h

@@ -52,6 +52,7 @@ struct kvm_riscv_config {
 	unsigned long mvendorid;
 	unsigned long marchid;
 	unsigned long mimpid;
+	unsigned long zicboz_block_size;
 };
 
 /* CORE registers for KVM_GET_ONE_REG and KVM_SET_ONE_REG */
@@ -105,6 +106,7 @@ enum KVM_RISCV_ISA_EXT_ID {
 	KVM_RISCV_ISA_EXT_SVINVAL,
 	KVM_RISCV_ISA_EXT_ZIHINTPAUSE,
 	KVM_RISCV_ISA_EXT_ZICBOM,
+	KVM_RISCV_ISA_EXT_ZICBOZ,
 	KVM_RISCV_ISA_EXT_MAX,
 };
 

arch/riscv/include/uapi/asm/unistd.h

@@ -43,3 +43,12 @@
 #define __NR_riscv_flush_icache (__NR_arch_specific_syscall + 15)
 #endif
 __SYSCALL(__NR_riscv_flush_icache, sys_riscv_flush_icache)
+
+/*
+ * Allows userspace to query the kernel for CPU architecture and
+ * microarchitecture details across a given set of CPUs.
+ */
+#ifndef __NR_riscv_hwprobe
+#define __NR_riscv_hwprobe (__NR_arch_specific_syscall + 14)
+#endif
+__SYSCALL(__NR_riscv_hwprobe, sys_riscv_hwprobe)

arch/riscv/kernel/Makefile

@@ -68,8 +68,6 @@ obj-$(CONFIG_CPU_PM)		+= suspend_entry.o suspend.o
 obj-$(CONFIG_FUNCTION_TRACER)	+= mcount.o ftrace.o
 obj-$(CONFIG_DYNAMIC_FTRACE)	+= mcount-dyn.o
 
-obj-$(CONFIG_TRACE_IRQFLAGS)	+= trace_irq.o
-
 obj-$(CONFIG_PERF_EVENTS)	+= perf_callchain.o
 obj-$(CONFIG_HAVE_PERF_REGS)	+= perf_regs.o
 obj-$(CONFIG_RISCV_SBI)		+= sbi.o
@@ -90,3 +88,5 @@ obj-$(CONFIG_EFI)		+= efi.o
 obj-$(CONFIG_COMPAT)		+= compat_syscall_table.o
 obj-$(CONFIG_COMPAT)		+= compat_signal.o
 obj-$(CONFIG_COMPAT)		+= compat_vdso/
+
+obj-$(CONFIG_64BIT)		+= pi/

arch/riscv/kernel/alternative.c

@@ -27,9 +27,11 @@ struct cpu_manufacturer_info_t {
 	void (*patch_func)(struct alt_entry *begin, struct alt_entry *end,
 				  unsigned long archid, unsigned long impid,
 				  unsigned int stage);
+	void (*feature_probe_func)(unsigned int cpu, unsigned long archid,
+				   unsigned long impid);
 };
 
-static void __init_or_module riscv_fill_cpu_mfr_info(struct cpu_manufacturer_info_t *cpu_mfr_info)
+static void riscv_fill_cpu_mfr_info(struct cpu_manufacturer_info_t *cpu_mfr_info)
 {
 #ifdef CONFIG_RISCV_M_MODE
 	cpu_mfr_info->vendor_id = csr_read(CSR_MVENDORID);
@@ -41,6 +43,7 @@ static void __init_or_module riscv_fill_cpu_mfr_info(struct cpu_manufacturer_inf
 	cpu_mfr_info->imp_id = sbi_get_mimpid();
 #endif
 
+	cpu_mfr_info->feature_probe_func = NULL;
 	switch (cpu_mfr_info->vendor_id) {
 #ifdef CONFIG_ERRATA_SIFIVE
 	case SIFIVE_VENDOR_ID:
@@ -50,6 +53,7 @@ static void __init_or_module riscv_fill_cpu_mfr_info(struct cpu_manufacturer_inf
 #ifdef CONFIG_ERRATA_THEAD
 	case THEAD_VENDOR_ID:
 		cpu_mfr_info->patch_func = thead_errata_patch_func;
+		cpu_mfr_info->feature_probe_func = thead_feature_probe_func;
 		break;
 #endif
 	default:
@@ -139,6 +143,20 @@ void riscv_alternative_fix_offsets(void *alt_ptr, unsigned int len,
 	}
 }
 
+/* Called on each CPU as it starts */
+void probe_vendor_features(unsigned int cpu)
+{
+	struct cpu_manufacturer_info_t cpu_mfr_info;
+
+	riscv_fill_cpu_mfr_info(&cpu_mfr_info);
+	if (!cpu_mfr_info.feature_probe_func)
+		return;
+
+	cpu_mfr_info.feature_probe_func(cpu,
+					cpu_mfr_info.arch_id,
+					cpu_mfr_info.imp_id);
+}
+
 /*
  * This is called very early in the boot process (directly after we run
  * a feature detect on the boot CPU). No need to worry about other CPUs
@@ -193,6 +211,7 @@ void __init apply_boot_alternatives(void)
 	/* If called on non-boot cpu things could go wrong */
 	WARN_ON(smp_processor_id() != 0);
 
+	probe_vendor_features(0);
 	_apply_alternatives((struct alt_entry *)__alt_start,
 			    (struct alt_entry *)__alt_end,
 			    RISCV_ALTERNATIVES_BOOT);

arch/riscv/kernel/cacheinfo.c

@@ -63,53 +63,12 @@ uintptr_t get_cache_geometry(u32 level, enum cache_type type)
 			   0;
 }
 
-static void ci_leaf_init(struct cacheinfo *this_leaf, enum cache_type type,
-			 unsigned int level, unsigned int size,
-			 unsigned int sets, unsigned int line_size)
+static void ci_leaf_init(struct cacheinfo *this_leaf,
+			 struct device_node *node,
+			 enum cache_type type, unsigned int level)
 {
 	this_leaf->level = level;
 	this_leaf->type = type;
-	this_leaf->size = size;
-	this_leaf->number_of_sets = sets;
-	this_leaf->coherency_line_size = line_size;
-
-	/*
-	 * If the cache is fully associative, there is no need to
-	 * check the other properties.
-	 */
-	if (sets == 1)
-		return;
-
-	/*
-	 * Set the ways number for n-ways associative, make sure
-	 * all properties are big than zero.
-	 */
-	if (sets > 0 && size > 0 && line_size > 0)
-		this_leaf->ways_of_associativity = (size / sets) / line_size;
-}
-
-static void fill_cacheinfo(struct cacheinfo **this_leaf,
-			   struct device_node *node, unsigned int level)
-{
-	unsigned int size, sets, line_size;
-
-	if (!of_property_read_u32(node, "cache-size", &size) &&
-	    !of_property_read_u32(node, "cache-block-size", &line_size) &&
-	    !of_property_read_u32(node, "cache-sets", &sets)) {
-		ci_leaf_init((*this_leaf)++, CACHE_TYPE_UNIFIED, level, size, sets, line_size);
-	}
-
-	if (!of_property_read_u32(node, "i-cache-size", &size) &&
-	    !of_property_read_u32(node, "i-cache-sets", &sets) &&
-	    !of_property_read_u32(node, "i-cache-block-size", &line_size)) {
-		ci_leaf_init((*this_leaf)++, CACHE_TYPE_INST, level, size, sets, line_size);
-	}
-
-	if (!of_property_read_u32(node, "d-cache-size", &size) &&
-	    !of_property_read_u32(node, "d-cache-sets", &sets) &&
-	    !of_property_read_u32(node, "d-cache-block-size", &line_size)) {
-		ci_leaf_init((*this_leaf)++, CACHE_TYPE_DATA, level, size, sets, line_size);
-	}
 }
 
 int populate_cache_leaves(unsigned int cpu)
@@ -120,24 +79,29 @@ int populate_cache_leaves(unsigned int cpu)
 	struct device_node *prev = NULL;
 	int levels = 1, level = 1;
 
-	/* Level 1 caches in cpu node */
-	fill_cacheinfo(&this_leaf, np, level);
+	if (of_property_read_bool(np, "cache-size"))
+		ci_leaf_init(this_leaf++, np, CACHE_TYPE_UNIFIED, level);
+	if (of_property_read_bool(np, "i-cache-size"))
+		ci_leaf_init(this_leaf++, np, CACHE_TYPE_INST, level);
+	if (of_property_read_bool(np, "d-cache-size"))
+		ci_leaf_init(this_leaf++, np, CACHE_TYPE_DATA, level);
 
-	/* Next level caches in cache nodes */
 	prev = np;
 	while ((np = of_find_next_cache_node(np))) {
 		of_node_put(prev);
 		prev = np;
-
 		if (!of_device_is_compatible(np, "cache"))
 			break;
 		if (of_property_read_u32(np, "cache-level", &level))
 			break;
 		if (level <= levels)
 			break;
-
-		fill_cacheinfo(&this_leaf, np, level);
-
+		if (of_property_read_bool(np, "cache-size"))
+			ci_leaf_init(this_leaf++, np, CACHE_TYPE_UNIFIED, level);
+		if (of_property_read_bool(np, "i-cache-size"))
+			ci_leaf_init(this_leaf++, np, CACHE_TYPE_INST, level);
+		if (of_property_read_bool(np, "d-cache-size"))
+			ci_leaf_init(this_leaf++, np, CACHE_TYPE_DATA, level);
 		levels = level;
 	}
 	of_node_put(np);

arch/riscv/kernel/compat_vdso/Makefile

@@ -26,7 +26,7 @@ targets := $(obj-compat_vdso) compat_vdso.so compat_vdso.so.dbg compat_vdso.lds
 obj-compat_vdso := $(addprefix $(obj)/, $(obj-compat_vdso))
 
 obj-y += compat_vdso.o
-CPPFLAGS_compat_vdso.lds += -P -C -U$(ARCH)
+CPPFLAGS_compat_vdso.lds += -P -C -DCOMPAT_VDSO -U$(ARCH)
 
 # Disable profiling and instrumentation for VDSO code
 GCOV_PROFILE := n

arch/riscv/kernel/cpu.c

@@ -7,6 +7,7 @@
 #include <linux/init.h>
 #include <linux/seq_file.h>
 #include <linux/of.h>
+#include <asm/cpufeature.h>
 #include <asm/csr.h>
 #include <asm/hwcap.h>
 #include <asm/sbi.h>
@@ -70,12 +71,7 @@ int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid)
 	return -1;
 }
 
-struct riscv_cpuinfo {
-	unsigned long mvendorid;
-	unsigned long marchid;
-	unsigned long mimpid;
-};
-static DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);
+DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);
 
 unsigned long riscv_cached_mvendorid(unsigned int cpu_id)
 {
@@ -186,11 +182,13 @@ arch_initcall(riscv_cpuinfo_init);
  */
 static struct riscv_isa_ext_data isa_ext_arr[] = {
 	__RISCV_ISA_EXT_DATA(zicbom, RISCV_ISA_EXT_ZICBOM),
+	__RISCV_ISA_EXT_DATA(zicboz, RISCV_ISA_EXT_ZICBOZ),
 	__RISCV_ISA_EXT_DATA(zihintpause, RISCV_ISA_EXT_ZIHINTPAUSE),
 	__RISCV_ISA_EXT_DATA(zbb, RISCV_ISA_EXT_ZBB),
 	__RISCV_ISA_EXT_DATA(sscofpmf, RISCV_ISA_EXT_SSCOFPMF),
 	__RISCV_ISA_EXT_DATA(sstc, RISCV_ISA_EXT_SSTC),
 	__RISCV_ISA_EXT_DATA(svinval, RISCV_ISA_EXT_SVINVAL),
+	__RISCV_ISA_EXT_DATA(svnapot, RISCV_ISA_EXT_SVNAPOT),
 	__RISCV_ISA_EXT_DATA(svpbmt, RISCV_ISA_EXT_SVPBMT),
 	__RISCV_ISA_EXT_DATA("", RISCV_ISA_EXT_MAX),
 };

arch/riscv/kernel/cpufeature.c

@@ -8,20 +8,15 @@
 
 #include <linux/bitmap.h>
 #include <linux/ctype.h>
-#include <linux/libfdt.h>
 #include <linux/log2.h>
 #include <linux/memory.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <asm/alternative.h>
 #include <asm/cacheflush.h>
-#include <asm/errata_list.h>
 #include <asm/hwcap.h>
 #include <asm/patch.h>
-#include <asm/pgtable.h>
 #include <asm/processor.h>
-#include <asm/smp.h>
-#include <asm/switch_to.h>
 
 #define NUM_ALPHA_EXTS ('z' - 'a' + 1)
 
@@ -30,6 +25,9 @@ unsigned long elf_hwcap __read_mostly;
 /* Host ISA bitmap */
 static DECLARE_BITMAP(riscv_isa, RISCV_ISA_EXT_MAX) __read_mostly;
 
+/* Performance information */
+DEFINE_PER_CPU(long, misaligned_access_speed);
+
 /**
  * riscv_isa_extension_base() - Get base extension word
  *
@@ -79,6 +77,15 @@ static bool riscv_isa_extension_check(int id)
 			return false;
 		}
 		return true;
+	case RISCV_ISA_EXT_ZICBOZ:
+		if (!riscv_cboz_block_size) {
+			pr_err("Zicboz detected in ISA string, but no cboz-block-size found\n");
+			return false;
+		} else if (!is_power_of_2(riscv_cboz_block_size)) {
+			pr_err("cboz-block-size present, but is not a power-of-2\n");
+			return false;
+		}
+		return true;
 	}
 
 	return true;
@@ -224,9 +231,11 @@ void __init riscv_fill_hwcap(void)
 				SET_ISA_EXT_MAP("sscofpmf", RISCV_ISA_EXT_SSCOFPMF);
 				SET_ISA_EXT_MAP("sstc", RISCV_ISA_EXT_SSTC);
 				SET_ISA_EXT_MAP("svinval", RISCV_ISA_EXT_SVINVAL);
+				SET_ISA_EXT_MAP("svnapot", RISCV_ISA_EXT_SVNAPOT);
 				SET_ISA_EXT_MAP("svpbmt", RISCV_ISA_EXT_SVPBMT);
 				SET_ISA_EXT_MAP("zbb", RISCV_ISA_EXT_ZBB);
 				SET_ISA_EXT_MAP("zicbom", RISCV_ISA_EXT_ZICBOM);
+				SET_ISA_EXT_MAP("zicboz", RISCV_ISA_EXT_ZICBOZ);
 				SET_ISA_EXT_MAP("zihintpause", RISCV_ISA_EXT_ZIHINTPAUSE);
 			}
 #undef SET_ISA_EXT_MAP
@@ -269,12 +278,46 @@ void __init riscv_fill_hwcap(void)
 }
 
 #ifdef CONFIG_RISCV_ALTERNATIVE
+/*
+ * Alternative patch sites consider 48 bits when determining when to patch
+ * the old instruction sequence with the new. These bits are broken into a
+ * 16-bit vendor ID and a 32-bit patch ID. A non-zero vendor ID means the
+ * patch site is for an erratum, identified by the 32-bit patch ID. When
+ * the vendor ID is zero, the patch site is for a cpufeature. cpufeatures
+ * further break down patch ID into two 16-bit numbers. The lower 16 bits
+ * are the cpufeature ID and the upper 16 bits are used for a value specific
+ * to the cpufeature and patch site. If the upper 16 bits are zero, then it
+ * implies no specific value is specified. cpufeatures that want to control
+ * patching on a per-site basis will provide non-zero values and implement
+ * checks here. The checks return true when patching should be done, and
+ * false otherwise.
+ */
+static bool riscv_cpufeature_patch_check(u16 id, u16 value)
+{
+	if (!value)
+		return true;
+
+	switch (id) {
+	case RISCV_ISA_EXT_ZICBOZ:
+		/*
+		 * Zicboz alternative applications provide the maximum
+		 * supported block size order, or zero when it doesn't
+		 * matter. If the current block size exceeds the maximum,
+		 * then the alternative cannot be applied.
+		 */
+		return riscv_cboz_block_size <= (1U << value);
+	}
+
+	return false;
+}
+
 void __init_or_module riscv_cpufeature_patch_func(struct alt_entry *begin,
 						  struct alt_entry *end,
 						  unsigned int stage)
 {
 	struct alt_entry *alt;
 	void *oldptr, *altptr;
+	u16 id, value;
 
 	if (stage == RISCV_ALTERNATIVES_EARLY_BOOT)
 		return;
@@ -282,13 +325,19 @@ void __init_or_module riscv_cpufeature_patch_func(struct alt_entry *begin,
 	for (alt = begin; alt < end; alt++) {
 		if (alt->vendor_id != 0)
 			continue;
-		if (alt->errata_id >= RISCV_ISA_EXT_MAX) {
-			WARN(1, "This extension id:%d is not in ISA extension list",
-				alt->errata_id);
+
+		id = PATCH_ID_CPUFEATURE_ID(alt->patch_id);
+
+		if (id >= RISCV_ISA_EXT_MAX) {
+			WARN(1, "This extension id:%d is not in ISA extension list", id);
 			continue;
 		}
 
-		if (!__riscv_isa_extension_available(NULL, alt->errata_id))
+		if (!__riscv_isa_extension_available(NULL, id))
+			continue;
+
+		value = PATCH_ID_CPUFEATURE_VALUE(alt->patch_id);
+		if (!riscv_cpufeature_patch_check(id, value))
 			continue;
 
 		oldptr = ALT_OLD_PTR(alt);

arch/riscv/kernel/efi-header.S

@@ -6,6 +6,7 @@
 
 #include <linux/pe.h>
 #include <linux/sizes.h>
+#include <asm/set_memory.h>
 
 	.macro	__EFI_PE_HEADER
 	.long	PE_MAGIC
@@ -33,7 +34,11 @@ optional_header:
 	.byte	0x02					// MajorLinkerVersion
 	.byte	0x14					// MinorLinkerVersion
 	.long	__pecoff_text_end - efi_header_end	// SizeOfCode
-	.long	__pecoff_data_virt_size			// SizeOfInitializedData
+#ifdef __clang__
+	.long   __pecoff_data_virt_size			// SizeOfInitializedData
+#else
+	.long	__pecoff_data_virt_end - __pecoff_text_end	// SizeOfInitializedData
+#endif
 	.long	0					// SizeOfUninitializedData
 	.long	__efistub_efi_pe_entry - _start		// AddressOfEntryPoint
 	.long	efi_header_end - _start			// BaseOfCode
@@ -91,9 +96,17 @@ section_table:
 		IMAGE_SCN_MEM_EXECUTE			// Characteristics
 
 	.ascii	".data\0\0\0"
-	.long	__pecoff_data_virt_size			// VirtualSize
+#ifdef __clang__
+	.long   __pecoff_data_virt_size			// VirtualSize
+#else
+	.long	__pecoff_data_virt_end - __pecoff_text_end	// VirtualSize
+#endif
 	.long	__pecoff_text_end - _start		// VirtualAddress
-	.long	__pecoff_data_raw_size			// SizeOfRawData
+#ifdef __clang__
+	.long   __pecoff_data_raw_size			// SizeOfRawData
+#else
+	.long	__pecoff_data_raw_end - __pecoff_text_end	// SizeOfRawData
+#endif
 	.long	__pecoff_text_end - _start		// PointerToRawData
 
 	.long	0					// PointerToRelocations

arch/riscv/kernel/entry.S

@@ -14,11 +14,7 @@
 #include <asm/asm-offsets.h>
 #include <asm/errata_list.h>
 
-#if !IS_ENABLED(CONFIG_PREEMPTION)
-.set resume_kernel, restore_all
-#endif
-
-ENTRY(handle_exception)
+SYM_CODE_START(handle_exception)
 	/*
 	 * If coming from userspace, preserve the user thread pointer and load
 	 * the kernel thread pointer.  If we came from the kernel, the scratch
@@ -46,32 +42,7 @@ _save_context:
 	REG_S x1,  PT_RA(sp)
 	REG_S x3,  PT_GP(sp)
 	REG_S x5,  PT_T0(sp)
-	REG_S x6,  PT_T1(sp)
-	REG_S x7,  PT_T2(sp)
-	REG_S x8,  PT_S0(sp)
-	REG_S x9,  PT_S1(sp)
-	REG_S x10, PT_A0(sp)
-	REG_S x11, PT_A1(sp)
-	REG_S x12, PT_A2(sp)
-	REG_S x13, PT_A3(sp)
-	REG_S x14, PT_A4(sp)
-	REG_S x15, PT_A5(sp)
-	REG_S x16, PT_A6(sp)
-	REG_S x17, PT_A7(sp)
-	REG_S x18, PT_S2(sp)
-	REG_S x19, PT_S3(sp)
-	REG_S x20, PT_S4(sp)
-	REG_S x21, PT_S5(sp)
-	REG_S x22, PT_S6(sp)
-	REG_S x23, PT_S7(sp)
-	REG_S x24, PT_S8(sp)
-	REG_S x25, PT_S9(sp)
-	REG_S x26, PT_S10(sp)
-	REG_S x27, PT_S11(sp)
-	REG_S x28, PT_T3(sp)
-	REG_S x29, PT_T4(sp)
-	REG_S x30, PT_T5(sp)
-	REG_S x31, PT_T6(sp)
+	save_from_x6_to_x31
 
 	/*
 	 * Disable user-mode memory access as it should only be set in the
@@ -106,19 +77,8 @@ _save_context:
 .option norelax
 	la gp, __global_pointer$
 .option pop
-
-#ifdef CONFIG_TRACE_IRQFLAGS
-	call __trace_hardirqs_off
-#endif
-
-#ifdef CONFIG_CONTEXT_TRACKING_USER
-	/* If previous state is in user mode, call user_exit_callable(). */
-	li   a0, SR_PP
-	and a0, s1, a0
-	bnez a0, skip_context_tracking
-	call user_exit_callable
-skip_context_tracking:
-#endif
+	move a0, sp /* pt_regs */
+	la ra, ret_from_exception
 
 	/*
 	 * MSB of cause differentiates between
@@ -126,38 +86,13 @@ skip_context_tracking:
 	 */
 	bge s4, zero, 1f
 
-	la ra, ret_from_exception
-
 	/* Handle interrupts */
-	move a0, sp /* pt_regs */
-	la a1, generic_handle_arch_irq
-	jr a1
+	tail do_irq
 1:
-	/*
-	 * Exceptions run with interrupts enabled or disabled depending on the
-	 * state of SR_PIE in m/sstatus.
-	 */
-	andi t0, s1, SR_PIE
-	beqz t0, 1f
-	/* kprobes, entered via ebreak, must have interrupts disabled. */
-	li t0, EXC_BREAKPOINT
-	beq s4, t0, 1f
-#ifdef CONFIG_TRACE_IRQFLAGS
-	call __trace_hardirqs_on
-#endif
-	csrs CSR_STATUS, SR_IE
-
-1:
-	la ra, ret_from_exception
-	/* Handle syscalls */
-	li t0, EXC_SYSCALL
-	beq s4, t0, handle_syscall
-
 	/* Handle other exceptions */
 	slli t0, s4, RISCV_LGPTR
 	la t1, excp_vect_table
 	la t2, excp_vect_table_end
-	move a0, sp /* pt_regs */
 	add t0, t1, t0
 	/* Check if exception code lies within bounds */
 	bgeu t0, t2, 1f
@@ -165,95 +100,16 @@ skip_context_tracking:
 	jr t0
 1:
 	tail do_trap_unknown
+SYM_CODE_END(handle_exception)
 
-handle_syscall:
-#ifdef CONFIG_RISCV_M_MODE
-	/*
-	 * When running is M-Mode (no MMU config), MPIE does not get set.
-	 * As a result, we need to force enable interrupts here because
-	 * handle_exception did not do set SR_IE as it always sees SR_PIE
-	 * being cleared.
-	 */
-	csrs CSR_STATUS, SR_IE
-#endif
-#if defined(CONFIG_TRACE_IRQFLAGS) || defined(CONFIG_CONTEXT_TRACKING_USER)
-	/* Recover a0 - a7 for system calls */
-	REG_L a0, PT_A0(sp)
-	REG_L a1, PT_A1(sp)
-	REG_L a2, PT_A2(sp)
-	REG_L a3, PT_A3(sp)
-	REG_L a4, PT_A4(sp)
-	REG_L a5, PT_A5(sp)
-	REG_L a6, PT_A6(sp)
-	REG_L a7, PT_A7(sp)
-#endif
-	 /* save the initial A0 value (needed in signal handlers) */
-	REG_S a0, PT_ORIG_A0(sp)
-	/*
-	 * Advance SEPC to avoid executing the original
-	 * scall instruction on sret
-	 */
-	addi s2, s2, 0x4
-	REG_S s2, PT_EPC(sp)
-	/* Trace syscalls, but only if requested by the user. */
-	REG_L t0, TASK_TI_FLAGS(tp)
-	andi t0, t0, _TIF_SYSCALL_WORK
-	bnez t0, handle_syscall_trace_enter
-check_syscall_nr:
-	/* Check to make sure we don't jump to a bogus syscall number. */
-	li t0, __NR_syscalls
-	la s0, sys_ni_syscall
-	/*
-	 * Syscall number held in a7.
-	 * If syscall number is above allowed value, redirect to ni_syscall.
-	 */
-	bgeu a7, t0, 3f
-#ifdef CONFIG_COMPAT
-	REG_L s0, PT_STATUS(sp)
-	srli s0, s0, SR_UXL_SHIFT
-	andi s0, s0, (SR_UXL >> SR_UXL_SHIFT)
-	li t0, (SR_UXL_32 >> SR_UXL_SHIFT)
-	sub t0, s0, t0
-	bnez t0, 1f
-
-	/* Call compat_syscall */
-	la s0, compat_sys_call_table
-	j 2f
-1:
-#endif
-	/* Call syscall */
-	la s0, sys_call_table
-2:
-	slli t0, a7, RISCV_LGPTR
-	add s0, s0, t0
-	REG_L s0, 0(s0)
-3:
-	jalr s0
-
-ret_from_syscall:
-	/* Set user a0 to kernel a0 */
-	REG_S a0, PT_A0(sp)
-	/*
-	 * We didn't execute the actual syscall.
-	 * Seccomp already set return value for the current task pt_regs.
-	 * (If it was configured with SECCOMP_RET_ERRNO/TRACE)
-	 */
-ret_from_syscall_rejected:
-#ifdef CONFIG_DEBUG_RSEQ
-	move a0, sp
-	call rseq_syscall
-#endif
-	/* Trace syscalls, but only if requested by the user. */
-	REG_L t0, TASK_TI_FLAGS(tp)
-	andi t0, t0, _TIF_SYSCALL_WORK
-	bnez t0, handle_syscall_trace_exit
-
+/*
+ * The ret_from_exception must be called with interrupt disabled. Here is the
+ * caller list:
+ *  - handle_exception
+ *  - ret_from_fork
+ */
 SYM_CODE_START_NOALIGN(ret_from_exception)
 	REG_L s0, PT_STATUS(sp)
-	csrc CSR_STATUS, SR_IE
-#ifdef CONFIG_TRACE_IRQFLAGS
-	call __trace_hardirqs_off
-#endif
 #ifdef CONFIG_RISCV_M_MODE
 	/* the MPP value is too large to be used as an immediate arg for addi */
 	li t0, SR_MPP
@@ -261,17 +117,7 @@ SYM_CODE_START_NOALIGN(ret_from_exception)
 #else
 	andi s0, s0, SR_SPP
 #endif
-	bnez s0, resume_kernel
-SYM_CODE_END(ret_from_exception)
-
-	/* Interrupts must be disabled here so flags are checked atomically */
-	REG_L s0, TASK_TI_FLAGS(tp) /* current_thread_info->flags */
-	andi s1, s0, _TIF_WORK_MASK
-	bnez s1, resume_userspace_slow
-resume_userspace:
-#ifdef CONFIG_CONTEXT_TRACKING_USER
-	call user_enter_callable
-#endif
+	bnez s0, 1f
 
 	/* Save unwound kernel stack pointer in thread_info */
 	addi s0, sp, PT_SIZE_ON_STACK
@@ -282,18 +128,7 @@ resume_userspace:
 	 * structures again.
 	 */
 	csrw CSR_SCRATCH, tp
-
-restore_all:
-#ifdef CONFIG_TRACE_IRQFLAGS
-	REG_L s1, PT_STATUS(sp)
-	andi t0, s1, SR_PIE
-	beqz t0, 1f
-	call __trace_hardirqs_on
-	j 2f
 1:
-	call __trace_hardirqs_off
-2:
-#endif
 	REG_L a0, PT_STATUS(sp)
 	/*
 	 * The current load reservation is effectively part of the processor's
@@ -322,32 +157,7 @@ restore_all:
 	REG_L x3,  PT_GP(sp)
 	REG_L x4,  PT_TP(sp)
 	REG_L x5,  PT_T0(sp)
-	REG_L x6,  PT_T1(sp)
-	REG_L x7,  PT_T2(sp)
-	REG_L x8,  PT_S0(sp)
-	REG_L x9,  PT_S1(sp)
-	REG_L x10, PT_A0(sp)
-	REG_L x11, PT_A1(sp)
-	REG_L x12, PT_A2(sp)
-	REG_L x13, PT_A3(sp)
-	REG_L x14, PT_A4(sp)
-	REG_L x15, PT_A5(sp)
-	REG_L x16, PT_A6(sp)
-	REG_L x17, PT_A7(sp)
-	REG_L x18, PT_S2(sp)
-	REG_L x19, PT_S3(sp)
-	REG_L x20, PT_S4(sp)
-	REG_L x21, PT_S5(sp)
-	REG_L x22, PT_S6(sp)
-	REG_L x23, PT_S7(sp)
-	REG_L x24, PT_S8(sp)
-	REG_L x25, PT_S9(sp)
-	REG_L x26, PT_S10(sp)
-	REG_L x27, PT_S11(sp)
-	REG_L x28, PT_T3(sp)
-	REG_L x29, PT_T4(sp)
-	REG_L x30, PT_T5(sp)
-	REG_L x31, PT_T6(sp)
+	restore_from_x6_to_x31
 
 	REG_L x2,  PT_SP(sp)
 
@@ -356,47 +166,10 @@ restore_all:
 #else
 	sret
 #endif
-
-#if IS_ENABLED(CONFIG_PREEMPTION)
-resume_kernel:
-	REG_L s0, TASK_TI_PREEMPT_COUNT(tp)
-	bnez s0, restore_all
-	REG_L s0, TASK_TI_FLAGS(tp)
-	andi s0, s0, _TIF_NEED_RESCHED
-	beqz s0, restore_all
-	call preempt_schedule_irq
-	j restore_all
-#endif
-
-resume_userspace_slow:
-	/* Enter slow path for supplementary processing */
-	move a0, sp /* pt_regs */
-	move a1, s0 /* current_thread_info->flags */
-	call do_work_pending
-	j resume_userspace
-
-/* Slow paths for ptrace. */
-handle_syscall_trace_enter:
-	move a0, sp
-	call do_syscall_trace_enter
-	move t0, a0
-	REG_L a0, PT_A0(sp)
-	REG_L a1, PT_A1(sp)
-	REG_L a2, PT_A2(sp)
-	REG_L a3, PT_A3(sp)
-	REG_L a4, PT_A4(sp)
-	REG_L a5, PT_A5(sp)
-	REG_L a6, PT_A6(sp)
-	REG_L a7, PT_A7(sp)
-	bnez t0, ret_from_syscall_rejected
-	j check_syscall_nr
-handle_syscall_trace_exit:
-	move a0, sp
-	call do_syscall_trace_exit
-	j ret_from_exception
+SYM_CODE_END(ret_from_exception)
 
 #ifdef CONFIG_VMAP_STACK
-handle_kernel_stack_overflow:
+SYM_CODE_START_LOCAL(handle_kernel_stack_overflow)
 	/*
 	 * Takes the psuedo-spinlock for the shadow stack, in case multiple
 	 * harts are concurrently overflowing their kernel stacks.  We could
@@ -464,32 +237,7 @@ restore_caller_reg:
 	REG_S x1,  PT_RA(sp)
 	REG_S x3,  PT_GP(sp)
 	REG_S x5,  PT_T0(sp)
-	REG_S x6,  PT_T1(sp)
-	REG_S x7,  PT_T2(sp)
-	REG_S x8,  PT_S0(sp)
-	REG_S x9,  PT_S1(sp)
-	REG_S x10, PT_A0(sp)
-	REG_S x11, PT_A1(sp)
-	REG_S x12, PT_A2(sp)
-	REG_S x13, PT_A3(sp)
-	REG_S x14, PT_A4(sp)
-	REG_S x15, PT_A5(sp)
-	REG_S x16, PT_A6(sp)
-	REG_S x17, PT_A7(sp)
-	REG_S x18, PT_S2(sp)
-	REG_S x19, PT_S3(sp)
-	REG_S x20, PT_S4(sp)
-	REG_S x21, PT_S5(sp)
-	REG_S x22, PT_S6(sp)
-	REG_S x23, PT_S7(sp)
-	REG_S x24, PT_S8(sp)
-	REG_S x25, PT_S9(sp)
-	REG_S x26, PT_S10(sp)
-	REG_S x27, PT_S11(sp)
-	REG_S x28, PT_T3(sp)
-	REG_S x29, PT_T4(sp)
-	REG_S x30, PT_T5(sp)
-	REG_S x31, PT_T6(sp)
+	save_from_x6_to_x31
 
 	REG_L s0, TASK_TI_KERNEL_SP(tp)
 	csrr s1, CSR_STATUS
@@ -505,23 +253,20 @@ restore_caller_reg:
 	REG_S s5, PT_TP(sp)
 	move a0, sp
 	tail handle_bad_stack
+SYM_CODE_END(handle_kernel_stack_overflow)
 #endif
 
-END(handle_exception)
-
-ENTRY(ret_from_fork)
-	la ra, ret_from_exception
-	tail schedule_tail
-ENDPROC(ret_from_fork)
-
-ENTRY(ret_from_kernel_thread)
+SYM_CODE_START(ret_from_fork)
 	call schedule_tail
+	beqz s0, 1f	/* not from kernel thread */
 	/* Call fn(arg) */
-	la ra, ret_from_exception
 	move a0, s1
-	jr s0
-ENDPROC(ret_from_kernel_thread)
-
+	jalr s0
+1:
+	move a0, sp /* pt_regs */
+	la ra, ret_from_exception
+	tail syscall_exit_to_user_mode
+SYM_CODE_END(ret_from_fork)
 
 /*
  * Integer register context switch
@@ -533,7 +278,7 @@ ENDPROC(ret_from_kernel_thread)
  * The value of a0 and a1 must be preserved by this function, as that's how
  * arguments are passed to schedule_tail.
  */
-ENTRY(__switch_to)
+SYM_FUNC_START(__switch_to)
 	/* Save context into prev->thread */
 	li    a4,  TASK_THREAD_RA
 	add   a3, a0, a4
@@ -570,7 +315,7 @@ ENTRY(__switch_to)
 	/* The offset of thread_info in task_struct is zero. */
 	move tp, a1
 	ret
-ENDPROC(__switch_to)
+SYM_FUNC_END(__switch_to)
 
 #ifndef CONFIG_MMU
 #define do_page_fault do_trap_unknown
@@ -579,7 +324,7 @@ ENDPROC(__switch_to)
 	.section ".rodata"
 	.align LGREG
 	/* Exception vector table */
-ENTRY(excp_vect_table)
+SYM_CODE_START(excp_vect_table)
 	RISCV_PTR do_trap_insn_misaligned
 	ALT_INSN_FAULT(RISCV_PTR do_trap_insn_fault)
 	RISCV_PTR do_trap_insn_illegal
@@ -588,7 +333,7 @@ ENTRY(excp_vect_table)
 	RISCV_PTR do_trap_load_fault
 	RISCV_PTR do_trap_store_misaligned
 	RISCV_PTR do_trap_store_fault
-	RISCV_PTR do_trap_ecall_u /* system call, gets intercepted */
+	RISCV_PTR do_trap_ecall_u /* system call */
 	RISCV_PTR do_trap_ecall_s
 	RISCV_PTR do_trap_unknown
 	RISCV_PTR do_trap_ecall_m
@@ -598,11 +343,11 @@ ENTRY(excp_vect_table)
 	RISCV_PTR do_trap_unknown
 	RISCV_PTR do_page_fault   /* store page fault */
 excp_vect_table_end:
-END(excp_vect_table)
+SYM_CODE_END(excp_vect_table)
 
 #ifndef CONFIG_MMU
-ENTRY(__user_rt_sigreturn)
+SYM_CODE_START(__user_rt_sigreturn)
 	li a7, __NR_rt_sigreturn
 	scall
-END(__user_rt_sigreturn)
+SYM_CODE_END(__user_rt_sigreturn)
 #endif

arch/riscv/kernel/head.h

@@ -10,7 +10,6 @@
 
 extern atomic_t hart_lottery;
 
-asmlinkage void do_page_fault(struct pt_regs *regs);
 asmlinkage void __init setup_vm(uintptr_t dtb_pa);
 #ifdef CONFIG_XIP_KERNEL
 asmlinkage void __init __copy_data(void);

arch/riscv/kernel/image-vars.h

@@ -23,8 +23,6 @@
  * linked at. The routines below are all implemented in assembler in a
  * position independent manner
  */
-__efistub_strcmp		= strcmp;
-
 __efistub__start		= _start;
 __efistub__start_kernel		= _start_kernel;
 __efistub__end			= _end;

arch/riscv/kernel/mcount-dyn.S

@@ -66,66 +66,17 @@
 	REG_S x3,  PT_GP(sp)
 	REG_S x4,  PT_TP(sp)
 	REG_S x5,  PT_T0(sp)
-	REG_S x6,  PT_T1(sp)
-	REG_S x7,  PT_T2(sp)
-	REG_S x8,  PT_S0(sp)
-	REG_S x9,  PT_S1(sp)
-	REG_S x10, PT_A0(sp)
-	REG_S x11, PT_A1(sp)
-	REG_S x12, PT_A2(sp)
-	REG_S x13, PT_A3(sp)
-	REG_S x14, PT_A4(sp)
-	REG_S x15, PT_A5(sp)
-	REG_S x16, PT_A6(sp)
-	REG_S x17, PT_A7(sp)
-	REG_S x18, PT_S2(sp)
-	REG_S x19, PT_S3(sp)
-	REG_S x20, PT_S4(sp)
-	REG_S x21, PT_S5(sp)
-	REG_S x22, PT_S6(sp)
-	REG_S x23, PT_S7(sp)
-	REG_S x24, PT_S8(sp)
-	REG_S x25, PT_S9(sp)
-	REG_S x26, PT_S10(sp)
-	REG_S x27, PT_S11(sp)
-	REG_S x28, PT_T3(sp)
-	REG_S x29, PT_T4(sp)
-	REG_S x30, PT_T5(sp)
-	REG_S x31, PT_T6(sp)
+	save_from_x6_to_x31
 	.endm
 
 	.macro RESTORE_ALL
-	REG_L t0,  PT_EPC(sp)
 	REG_L x1,  PT_RA(sp)
 	REG_L x2,  PT_SP(sp)
 	REG_L x3,  PT_GP(sp)
 	REG_L x4,  PT_TP(sp)
-	REG_L x6,  PT_T1(sp)
-	REG_L x7,  PT_T2(sp)
-	REG_L x8,  PT_S0(sp)
-	REG_L x9,  PT_S1(sp)
-	REG_L x10, PT_A0(sp)
-	REG_L x11, PT_A1(sp)
-	REG_L x12, PT_A2(sp)
-	REG_L x13, PT_A3(sp)
-	REG_L x14, PT_A4(sp)
-	REG_L x15, PT_A5(sp)
-	REG_L x16, PT_A6(sp)
-	REG_L x17, PT_A7(sp)
-	REG_L x18, PT_S2(sp)
-	REG_L x19, PT_S3(sp)
-	REG_L x20, PT_S4(sp)
-	REG_L x21, PT_S5(sp)
-	REG_L x22, PT_S6(sp)
-	REG_L x23, PT_S7(sp)
-	REG_L x24, PT_S8(sp)
-	REG_L x25, PT_S9(sp)
-	REG_L x26, PT_S10(sp)
-	REG_L x27, PT_S11(sp)
-	REG_L x28, PT_T3(sp)
-	REG_L x29, PT_T4(sp)
-	REG_L x30, PT_T5(sp)
-	REG_L x31, PT_T6(sp)
+	/* Restore t0 with PT_EPC */
+	REG_L x5,  PT_EPC(sp)
+	restore_from_x6_to_x31
 
 	addi	sp, sp, PT_SIZE_ON_STACK
 	.endm

arch/riscv/kernel/pi/Makefile

@@ -0,0 +1,39 @@
+# SPDX-License-Identifier: GPL-2.0
+# This file was copied from arm64/kernel/pi/Makefile.
+
+KBUILD_CFLAGS	:= $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) -fpie \
+		   -Os -DDISABLE_BRANCH_PROFILING $(DISABLE_STACKLEAK_PLUGIN) \
+		   $(call cc-option,-mbranch-protection=none) \
+		   -I$(srctree)/scripts/dtc/libfdt -fno-stack-protector \
+		   -D__DISABLE_EXPORTS -ffreestanding \
+		   -fno-asynchronous-unwind-tables -fno-unwind-tables \
+		   $(call cc-option,-fno-addrsig)
+
+KBUILD_CFLAGS	+= -mcmodel=medany
+
+CFLAGS_cmdline_early.o += -D__NO_FORTIFY
+CFLAGS_lib-fdt_ro.o += -D__NO_FORTIFY
+
+GCOV_PROFILE	:= n
+KASAN_SANITIZE	:= n
+KCSAN_SANITIZE	:= n
+UBSAN_SANITIZE	:= n
+KCOV_INSTRUMENT	:= n
+
+$(obj)/%.pi.o: OBJCOPYFLAGS := --prefix-symbols=__pi_ \
+			       --remove-section=.note.gnu.property \
+			       --prefix-alloc-sections=.init
+$(obj)/%.pi.o: $(obj)/%.o FORCE
+	$(call if_changed,objcopy)
+
+$(obj)/lib-%.o: $(srctree)/lib/%.c FORCE
+	$(call if_changed_rule,cc_o_c)
+
+$(obj)/string.o: $(srctree)/lib/string.c FORCE
+	$(call if_changed_rule,cc_o_c)
+
+$(obj)/ctype.o: $(srctree)/lib/ctype.c FORCE
+	$(call if_changed_rule,cc_o_c)
+
+obj-y		:= cmdline_early.pi.o string.pi.o ctype.pi.o lib-fdt.pi.o lib-fdt_ro.pi.o
+extra-y		:= $(patsubst %.pi.o,%.o,$(obj-y))

arch/riscv/kernel/pi/cmdline_early.c

@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/libfdt.h>
+#include <linux/string.h>
+#include <asm/pgtable.h>
+#include <asm/setup.h>
+
+static char early_cmdline[COMMAND_LINE_SIZE];
+
+/*
+ * Declare the functions that are exported (but prefixed) here so that LLVM
+ * does not complain it lacks the 'static' keyword (which, if added, makes
+ * LLVM complain because the function is actually unused in this file).
+ */
+u64 set_satp_mode_from_cmdline(uintptr_t dtb_pa);
+
+static char *get_early_cmdline(uintptr_t dtb_pa)
+{
+	const char *fdt_cmdline = NULL;
+	unsigned int fdt_cmdline_size = 0;
+	int chosen_node;
+
+	if (!IS_ENABLED(CONFIG_CMDLINE_FORCE)) {
+		chosen_node = fdt_path_offset((void *)dtb_pa, "/chosen");
+		if (chosen_node >= 0) {
+			fdt_cmdline = fdt_getprop((void *)dtb_pa, chosen_node,
+						  "bootargs", NULL);
+			if (fdt_cmdline) {
+				fdt_cmdline_size = strlen(fdt_cmdline);
+				strscpy(early_cmdline, fdt_cmdline,
+					COMMAND_LINE_SIZE);
+			}
+		}
+	}
+
+	if (IS_ENABLED(CONFIG_CMDLINE_EXTEND) ||
+	    IS_ENABLED(CONFIG_CMDLINE_FORCE) ||
+	    fdt_cmdline_size == 0 /* CONFIG_CMDLINE_FALLBACK */) {
+		strncat(early_cmdline, CONFIG_CMDLINE,
+			COMMAND_LINE_SIZE - fdt_cmdline_size);
+	}
+
+	return early_cmdline;
+}
+
+static u64 match_noXlvl(char *cmdline)
+{
+	if (strstr(cmdline, "no4lvl"))
+		return SATP_MODE_48;
+	else if (strstr(cmdline, "no5lvl"))
+		return SATP_MODE_57;
+
+	return 0;
+}
+
+u64 set_satp_mode_from_cmdline(uintptr_t dtb_pa)
+{
+	char *cmdline = get_early_cmdline(dtb_pa);
+
+	return match_noXlvl(cmdline);
+}

arch/riscv/kernel/process.c

@@ -34,7 +34,6 @@ EXPORT_SYMBOL(__stack_chk_guard);
 #endif
 
 extern asmlinkage void ret_from_fork(void);
-extern asmlinkage void ret_from_kernel_thread(void);
 
 void arch_cpu_idle(void)
 {
@@ -173,7 +172,6 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
 		/* Supervisor/Machine, irqs on: */
 		childregs->status = SR_PP | SR_PIE;
 
-		p->thread.ra = (unsigned long)ret_from_kernel_thread;
 		p->thread.s[0] = (unsigned long)args->fn;
 		p->thread.s[1] = (unsigned long)args->fn_arg;
 	} else {
@@ -183,8 +181,9 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
 		if (clone_flags & CLONE_SETTLS)
 			childregs->tp = tls;
 		childregs->a0 = 0; /* Return value of fork() */
-		p->thread.ra = (unsigned long)ret_from_fork;
+		p->thread.s[0] = 0;
 	}
+	p->thread.ra = (unsigned long)ret_from_fork;
 	p->thread.sp = (unsigned long)childregs; /* kernel sp */
 	return 0;
 }

arch/riscv/kernel/ptrace.c

@@ -19,9 +19,6 @@
 #include <linux/sched.h>
 #include <linux/sched/task_stack.h>
 
-#define CREATE_TRACE_POINTS
-#include <trace/events/syscalls.h>
-
 enum riscv_regset {
 	REGSET_X,
 #ifdef CONFIG_FPU
@@ -212,7 +209,6 @@ unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
 
 void ptrace_disable(struct task_struct *child)
 {
-	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
 }
 
 long arch_ptrace(struct task_struct *child, long request,
@@ -229,46 +225,6 @@ long arch_ptrace(struct task_struct *child, long request,
 	return ret;
 }
 
-/*
- * Allows PTRACE_SYSCALL to work.  These are called from entry.S in
- * {handle,ret_from}_syscall.
- */
-__visible int do_syscall_trace_enter(struct pt_regs *regs)
-{
-	if (test_thread_flag(TIF_SYSCALL_TRACE))
-		if (ptrace_report_syscall_entry(regs))
-			return -1;
-
-	/*
-	 * Do the secure computing after ptrace; failures should be fast.
-	 * If this fails we might have return value in a0 from seccomp
-	 * (via SECCOMP_RET_ERRNO/TRACE).
-	 */
-	if (secure_computing() == -1)
-		return -1;
-
-#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
-	if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
-		trace_sys_enter(regs, syscall_get_nr(current, regs));
-#endif
-
-	audit_syscall_entry(regs->a7, regs->a0, regs->a1, regs->a2, regs->a3);
-	return 0;
-}
-
-__visible void do_syscall_trace_exit(struct pt_regs *regs)
-{
-	audit_syscall_exit(regs);
-
-	if (test_thread_flag(TIF_SYSCALL_TRACE))
-		ptrace_report_syscall_exit(regs, 0);
-
-#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
-	if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
-		trace_sys_exit(regs, regs_return_value(regs));
-#endif
-}
-
 #ifdef CONFIG_COMPAT
 static int compat_riscv_gpr_get(struct task_struct *target,
 				const struct user_regset *regset,

arch/riscv/kernel/setup.c

@@ -293,7 +293,7 @@ void __init setup_arch(char **cmdline_p)
 	setup_smp();
 #endif
 
-	riscv_init_cbom_blocksize();
+	riscv_init_cbo_blocksizes();
 	riscv_fill_hwcap();
 	apply_boot_alternatives();
 	if (IS_ENABLED(CONFIG_RISCV_ISA_ZICBOM) &&

arch/riscv/kernel/signal.c

@@ -12,6 +12,7 @@
 #include <linux/syscalls.h>
 #include <linux/resume_user_mode.h>
 #include <linux/linkage.h>
+#include <linux/entry-common.h>
 
 #include <asm/ucontext.h>
 #include <asm/vdso.h>
@@ -281,7 +282,7 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
 	signal_setup_done(ret, ksig, 0);
 }
 
-static void do_signal(struct pt_regs *regs)
+void arch_do_signal_or_restart(struct pt_regs *regs)
 {
 	struct ksignal ksig;
 
@@ -318,29 +319,3 @@ static void do_signal(struct pt_regs *regs)
 	 */
 	restore_saved_sigmask();
 }
-
-/*
- * Handle any pending work on the resume-to-userspace path, as indicated by
- * _TIF_WORK_MASK. Entered from assembly with IRQs off.
- */
-asmlinkage __visible void do_work_pending(struct pt_regs *regs,
-					  unsigned long thread_info_flags)
-{
-	do {
-		if (thread_info_flags & _TIF_NEED_RESCHED) {
-			schedule();
-		} else {
-			local_irq_enable();
-			if (thread_info_flags & _TIF_UPROBE)
-				uprobe_notify_resume(regs);
-			/* Handle pending signal delivery */
-			if (thread_info_flags & (_TIF_SIGPENDING |
-						 _TIF_NOTIFY_SIGNAL))
-				do_signal(regs);
-			if (thread_info_flags & _TIF_NOTIFY_RESUME)
-				resume_user_mode_work(regs);
-		}
-		local_irq_disable();
-		thread_info_flags = read_thread_flags();
-	} while (thread_info_flags & _TIF_WORK_MASK);
-}

arch/riscv/kernel/smpboot.c

@@ -167,6 +167,7 @@ asmlinkage __visible void smp_callin(void)
 	notify_cpu_starting(curr_cpuid);
 	numa_add_cpu(curr_cpuid);
 	set_cpu_online(curr_cpuid, 1);
+	probe_vendor_features(curr_cpuid);
 
 	/*
 	 * Remote TLB flushes are ignored while the CPU is offline, so emit

arch/riscv/kernel/sys_riscv.c

@@ -6,9 +6,15 @@
  */
 
 #include <linux/syscalls.h>
-#include <asm/unistd.h>
 #include <asm/cacheflush.h>
+#include <asm/cpufeature.h>
+#include <asm/hwprobe.h>
+#include <asm/sbi.h>
+#include <asm/switch_to.h>
+#include <asm/uaccess.h>
+#include <asm/unistd.h>
 #include <asm-generic/mman-common.h>
+#include <vdso/vsyscall.h>
 
 static long riscv_sys_mmap(unsigned long addr, unsigned long len,
 			   unsigned long prot, unsigned long flags,
@@ -69,3 +75,225 @@ SYSCALL_DEFINE3(riscv_flush_icache, uintptr_t, start, uintptr_t, end,
 
 	return 0;
 }
+
+/*
+ * The hwprobe interface, for allowing userspace to probe to see which features
+ * are supported by the hardware.  See Documentation/riscv/hwprobe.rst for more
+ * details.
+ */
+static void hwprobe_arch_id(struct riscv_hwprobe *pair,
+			    const struct cpumask *cpus)
+{
+	u64 id = -1ULL;
+	bool first = true;
+	int cpu;
+
+	for_each_cpu(cpu, cpus) {
+		u64 cpu_id;
+
+		switch (pair->key) {
+		case RISCV_HWPROBE_KEY_MVENDORID:
+			cpu_id = riscv_cached_mvendorid(cpu);
+			break;
+		case RISCV_HWPROBE_KEY_MIMPID:
+			cpu_id = riscv_cached_mimpid(cpu);
+			break;
+		case RISCV_HWPROBE_KEY_MARCHID:
+			cpu_id = riscv_cached_marchid(cpu);
+			break;
+		}
+
+		if (first) {
+			id = cpu_id;
+			first = false;
+		}
+
+		/*
+		 * If there's a mismatch for the given set, return -1 in the
+		 * value.
+		 */
+		if (id != cpu_id) {
+			id = -1ULL;
+			break;
+		}
+	}
+
+	pair->value = id;
+}
+
+static u64 hwprobe_misaligned(const struct cpumask *cpus)
+{
+	int cpu;
+	u64 perf = -1ULL;
+
+	for_each_cpu(cpu, cpus) {
+		int this_perf = per_cpu(misaligned_access_speed, cpu);
+
+		if (perf == -1ULL)
+			perf = this_perf;
+
+		if (perf != this_perf) {
+			perf = RISCV_HWPROBE_MISALIGNED_UNKNOWN;
+			break;
+		}
+	}
+
+	if (perf == -1ULL)
+		return RISCV_HWPROBE_MISALIGNED_UNKNOWN;
+
+	return perf;
+}
+
+static void hwprobe_one_pair(struct riscv_hwprobe *pair,
+			     const struct cpumask *cpus)
+{
+	switch (pair->key) {
+	case RISCV_HWPROBE_KEY_MVENDORID:
+	case RISCV_HWPROBE_KEY_MARCHID:
+	case RISCV_HWPROBE_KEY_MIMPID:
+		hwprobe_arch_id(pair, cpus);
+		break;
+	/*
+	 * The kernel already assumes that the base single-letter ISA
+	 * extensions are supported on all harts, and only supports the
+	 * IMA base, so just cheat a bit here and tell that to
+	 * userspace.
+	 */
+	case RISCV_HWPROBE_KEY_BASE_BEHAVIOR:
+		pair->value = RISCV_HWPROBE_BASE_BEHAVIOR_IMA;
+		break;
+
+	case RISCV_HWPROBE_KEY_IMA_EXT_0:
+		pair->value = 0;
+		if (has_fpu())
+			pair->value |= RISCV_HWPROBE_IMA_FD;
+
+		if (riscv_isa_extension_available(NULL, c))
+			pair->value |= RISCV_HWPROBE_IMA_C;
+
+		break;
+
+	case RISCV_HWPROBE_KEY_CPUPERF_0:
+		pair->value = hwprobe_misaligned(cpus);
+		break;
+
+	/*
+	 * For forward compatibility, unknown keys don't fail the whole
+	 * call, but get their element key set to -1 and value set to 0
+	 * indicating they're unrecognized.
+	 */
+	default:
+		pair->key = -1;
+		pair->value = 0;
+		break;
+	}
+}
+
+static int do_riscv_hwprobe(struct riscv_hwprobe __user *pairs,
+			    size_t pair_count, size_t cpu_count,
+			    unsigned long __user *cpus_user,
+			    unsigned int flags)
+{
+	size_t out;
+	int ret;
+	cpumask_t cpus;
+
+	/* Check the reserved flags. */
+	if (flags != 0)
+		return -EINVAL;
+
+	/*
+	 * The interface supports taking in a CPU mask, and returns values that
+	 * are consistent across that mask. Allow userspace to specify NULL and
+	 * 0 as a shortcut to all online CPUs.
+	 */
+	cpumask_clear(&cpus);
+	if (!cpu_count && !cpus_user) {
+		cpumask_copy(&cpus, cpu_online_mask);
+	} else {
+		if (cpu_count > cpumask_size())
+			cpu_count = cpumask_size();
+
+		ret = copy_from_user(&cpus, cpus_user, cpu_count);
+		if (ret)
+			return -EFAULT;
+
+		/*
+		 * Userspace must provide at least one online CPU, without that
+		 * there's no way to define what is supported.
+		 */
+		cpumask_and(&cpus, &cpus, cpu_online_mask);
+		if (cpumask_empty(&cpus))
+			return -EINVAL;
+	}
+
+	for (out = 0; out < pair_count; out++, pairs++) {
+		struct riscv_hwprobe pair;
+
+		if (get_user(pair.key, &pairs->key))
+			return -EFAULT;
+
+		pair.value = 0;
+		hwprobe_one_pair(&pair, &cpus);
+		ret = put_user(pair.key, &pairs->key);
+		if (ret == 0)
+			ret = put_user(pair.value, &pairs->value);
+
+		if (ret)
+			return -EFAULT;
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_MMU
+
+static int __init init_hwprobe_vdso_data(void)
+{
+	struct vdso_data *vd = __arch_get_k_vdso_data();
+	struct arch_vdso_data *avd = &vd->arch_data;
+	u64 id_bitsmash = 0;
+	struct riscv_hwprobe pair;
+	int key;
+
+	/*
+	 * Initialize vDSO data with the answers for the "all CPUs" case, to
+	 * save a syscall in the common case.
+	 */
+	for (key = 0; key <= RISCV_HWPROBE_MAX_KEY; key++) {
+		pair.key = key;
+		hwprobe_one_pair(&pair, cpu_online_mask);
+
+		WARN_ON_ONCE(pair.key < 0);
+
+		avd->all_cpu_hwprobe_values[key] = pair.value;
+		/*
+		 * Smash together the vendor, arch, and impl IDs to see if
+		 * they're all 0 or any negative.
+		 */
+		if (key <= RISCV_HWPROBE_KEY_MIMPID)
+			id_bitsmash |= pair.value;
+	}
+
+	/*
+	 * If the arch, vendor, and implementation ID are all the same across
+	 * all harts, then assume all CPUs are the same, and allow the vDSO to
+	 * answer queries for arbitrary masks. However if all values are 0 (not
+	 * populated) or any value returns -1 (varies across CPUs), then the
+	 * vDSO should defer to the kernel for exotic cpu masks.
+	 */
+	avd->homogeneous_cpus = id_bitsmash != 0 && id_bitsmash != -1;
+	return 0;
+}
+
+arch_initcall_sync(init_hwprobe_vdso_data);
+
+#endif /* CONFIG_MMU */
+
+SYSCALL_DEFINE5(riscv_hwprobe, struct riscv_hwprobe __user *, pairs,
+		size_t, pair_count, size_t, cpu_count, unsigned long __user *,
+		cpus, unsigned int, flags)
+{
+	return do_riscv_hwprobe(pairs, pair_count, cpu_count,
+				cpus, flags);
+}

arch/riscv/kernel/trace_irq.c

@@ -1,27 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (C) 2022 Changbin Du <changbin.du@gmail.com>
- */
-
-#include <linux/irqflags.h>
-#include <linux/kprobes.h>
-#include "trace_irq.h"
-
-/*
- * trace_hardirqs_on/off require the caller to setup frame pointer properly.
- * Otherwise, CALLER_ADDR1 might trigger an pagging exception in kernel.
- * Here we add one extra level so they can be safely called by low
- * level entry code which $fp is used for other purpose.
- */
-
-void __trace_hardirqs_on(void)
-{
-	trace_hardirqs_on();
-}
-NOKPROBE_SYMBOL(__trace_hardirqs_on);
-
-void __trace_hardirqs_off(void)
-{
-	trace_hardirqs_off();
-}
-NOKPROBE_SYMBOL(__trace_hardirqs_off);

arch/riscv/kernel/trace_irq.h

@@ -1,11 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * Copyright (C) 2022 Changbin Du <changbin.du@gmail.com>
- */
-#ifndef __TRACE_IRQ_H
-#define __TRACE_IRQ_H
-
-void __trace_hardirqs_on(void);
-void __trace_hardirqs_off(void);
-
-#endif /* __TRACE_IRQ_H */

arch/riscv/kernel/traps.c

@@ -17,12 +17,14 @@
 #include <linux/module.h>
 #include <linux/irq.h>
 #include <linux/kexec.h>
+#include <linux/entry-common.h>
 
 #include <asm/asm-prototypes.h>
 #include <asm/bug.h>
 #include <asm/csr.h>
 #include <asm/processor.h>
 #include <asm/ptrace.h>
+#include <asm/syscall.h>
 #include <asm/thread_info.h>
 
 int show_unhandled_signals = 1;
@@ -119,14 +121,22 @@ static void do_trap_error(struct pt_regs *regs, int signo, int code,
 }
 
 #if defined(CONFIG_XIP_KERNEL) && defined(CONFIG_RISCV_ALTERNATIVE)
-#define __trap_section		__section(".xip.traps")
+#define __trap_section __noinstr_section(".xip.traps")
 #else
-#define __trap_section
+#define __trap_section noinstr
 #endif
-#define DO_ERROR_INFO(name, signo, code, str)				\
-asmlinkage __visible __trap_section void name(struct pt_regs *regs)	\
-{									\
-	do_trap_error(regs, signo, code, regs->epc, "Oops - " str);	\
+#define DO_ERROR_INFO(name, signo, code, str)					\
+asmlinkage __visible __trap_section void name(struct pt_regs *regs)		\
+{										\
+	if (user_mode(regs)) {							\
+		irqentry_enter_from_user_mode(regs);				\
+		do_trap_error(regs, signo, code, regs->epc, "Oops - " str);	\
+		irqentry_exit_to_user_mode(regs);				\
+	} else {								\
+		irqentry_state_t state = irqentry_nmi_enter(regs);		\
+		do_trap_error(regs, signo, code, regs->epc, "Oops - " str);	\
+		irqentry_nmi_exit(regs, state);					\
+	}									\
 }
 
 DO_ERROR_INFO(do_trap_unknown,
@@ -148,26 +158,50 @@ DO_ERROR_INFO(do_trap_store_misaligned,
 int handle_misaligned_load(struct pt_regs *regs);
 int handle_misaligned_store(struct pt_regs *regs);
 
-asmlinkage void __trap_section do_trap_load_misaligned(struct pt_regs *regs)
+asmlinkage __visible __trap_section void do_trap_load_misaligned(struct pt_regs *regs)
 {
-	if (!handle_misaligned_load(regs))
-		return;
-	do_trap_error(regs, SIGBUS, BUS_ADRALN, regs->epc,
-		      "Oops - load address misaligned");
+	if (user_mode(regs)) {
+		irqentry_enter_from_user_mode(regs);
+
+		if (handle_misaligned_load(regs))
+			do_trap_error(regs, SIGBUS, BUS_ADRALN, regs->epc,
+			      "Oops - load address misaligned");
+
+		irqentry_exit_to_user_mode(regs);
+	} else {
+		irqentry_state_t state = irqentry_nmi_enter(regs);
+
+		if (handle_misaligned_load(regs))
+			do_trap_error(regs, SIGBUS, BUS_ADRALN, regs->epc,
+			      "Oops - load address misaligned");
+
+		irqentry_nmi_exit(regs, state);
+	}
 }
 
-asmlinkage void __trap_section do_trap_store_misaligned(struct pt_regs *regs)
+asmlinkage __visible __trap_section void do_trap_store_misaligned(struct pt_regs *regs)
 {
-	if (!handle_misaligned_store(regs))
-		return;
-	do_trap_error(regs, SIGBUS, BUS_ADRALN, regs->epc,
-		      "Oops - store (or AMO) address misaligned");
+	if (user_mode(regs)) {
+		irqentry_enter_from_user_mode(regs);
+
+		if (handle_misaligned_store(regs))
+			do_trap_error(regs, SIGBUS, BUS_ADRALN, regs->epc,
+				"Oops - store (or AMO) address misaligned");
+
+		irqentry_exit_to_user_mode(regs);
+	} else {
+		irqentry_state_t state = irqentry_nmi_enter(regs);
+
+		if (handle_misaligned_store(regs))
+			do_trap_error(regs, SIGBUS, BUS_ADRALN, regs->epc,
+				"Oops - store (or AMO) address misaligned");
+
+		irqentry_nmi_exit(regs, state);
+	}
 }
 #endif
 DO_ERROR_INFO(do_trap_store_fault,
 	SIGSEGV, SEGV_ACCERR, "store (or AMO) access fault");
-DO_ERROR_INFO(do_trap_ecall_u,
-	SIGILL, ILL_ILLTRP, "environment call from U-mode");
 DO_ERROR_INFO(do_trap_ecall_s,
 	SIGILL, ILL_ILLTRP, "environment call from S-mode");
 DO_ERROR_INFO(do_trap_ecall_m,
@@ -183,7 +217,7 @@ static inline unsigned long get_break_insn_length(unsigned long pc)
 	return GET_INSN_LENGTH(insn);
 }
 
-asmlinkage __visible __trap_section void do_trap_break(struct pt_regs *regs)
+void handle_break(struct pt_regs *regs)
 {
 #ifdef CONFIG_KPROBES
 	if (kprobe_single_step_handler(regs))
@@ -213,7 +247,77 @@ asmlinkage __visible __trap_section void do_trap_break(struct pt_regs *regs)
 	else
 		die(regs, "Kernel BUG");
 }
-NOKPROBE_SYMBOL(do_trap_break);
+
+asmlinkage __visible __trap_section void do_trap_break(struct pt_regs *regs)
+{
+	if (user_mode(regs)) {
+		irqentry_enter_from_user_mode(regs);
+
+		handle_break(regs);
+
+		irqentry_exit_to_user_mode(regs);
+	} else {
+		irqentry_state_t state = irqentry_nmi_enter(regs);
+
+		handle_break(regs);
+
+		irqentry_nmi_exit(regs, state);
+	}
+}
+
+asmlinkage __visible __trap_section void do_trap_ecall_u(struct pt_regs *regs)
+{
+	if (user_mode(regs)) {
+		ulong syscall = regs->a7;
+
+		regs->epc += 4;
+		regs->orig_a0 = regs->a0;
+
+		syscall = syscall_enter_from_user_mode(regs, syscall);
+
+		if (syscall < NR_syscalls)
+			syscall_handler(regs, syscall);
+		else
+			regs->a0 = -ENOSYS;
+
+		syscall_exit_to_user_mode(regs);
+	} else {
+		irqentry_state_t state = irqentry_nmi_enter(regs);
+
+		do_trap_error(regs, SIGILL, ILL_ILLTRP, regs->epc,
+			"Oops - environment call from U-mode");
+
+		irqentry_nmi_exit(regs, state);
+	}
+
+}
+
+#ifdef CONFIG_MMU
+asmlinkage __visible noinstr void do_page_fault(struct pt_regs *regs)
+{
+	irqentry_state_t state = irqentry_enter(regs);
+
+	handle_page_fault(regs);
+
+	local_irq_disable();
+
+	irqentry_exit(regs, state);
+}
+#endif
+
+asmlinkage __visible noinstr void do_irq(struct pt_regs *regs)
+{
+	struct pt_regs *old_regs;
+	irqentry_state_t state = irqentry_enter(regs);
+
+	irq_enter_rcu();
+	old_regs = set_irq_regs(regs);
+	handle_arch_irq(regs);
+	set_irq_regs(old_regs);
+	irq_exit_rcu();
+
+	irqentry_exit(regs, state);
+}
 
 #ifdef CONFIG_GENERIC_BUG
 int is_valid_bugaddr(unsigned long pc)

arch/riscv/kernel/vdso.c

@@ -14,13 +14,7 @@
 #include <asm/page.h>
 #include <asm/vdso.h>
 #include <linux/time_namespace.h>
-
-#ifdef CONFIG_GENERIC_TIME_VSYSCALL
 #include <vdso/datapage.h>
-#else
-struct vdso_data {
-};
-#endif
 
 enum vvar_pages {
 	VVAR_DATA_PAGE_OFFSET,

arch/riscv/kernel/vdso/Makefile

@@ -10,6 +10,8 @@ vdso-syms += vgettimeofday
 endif
 vdso-syms += getcpu
 vdso-syms += flush_icache
+vdso-syms += hwprobe
+vdso-syms += sys_hwprobe
 
 # Files to link into the vdso
 obj-vdso = $(patsubst %, %.o, $(vdso-syms)) note.o
@@ -21,6 +23,8 @@ ifneq ($(c-gettimeofday-y),)
   CFLAGS_vgettimeofday.o += -fPIC -include $(c-gettimeofday-y)
 endif
 
+CFLAGS_hwprobe.o += -fPIC
+
 # Build rules
 targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds
 obj-vdso := $(addprefix $(obj)/, $(obj-vdso))

arch/riscv/kernel/vdso/hwprobe.c

@@ -0,0 +1,52 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2023 Rivos, Inc
+ */
+
+#include <linux/types.h>
+#include <vdso/datapage.h>
+#include <vdso/helpers.h>
+
+extern int riscv_hwprobe(struct riscv_hwprobe *pairs, size_t pair_count,
+			 size_t cpu_count, unsigned long *cpus,
+			 unsigned int flags);
+
+/* Add a prototype to avoid -Wmissing-prototypes warning. */
+int __vdso_riscv_hwprobe(struct riscv_hwprobe *pairs, size_t pair_count,
+			 size_t cpu_count, unsigned long *cpus,
+			 unsigned int flags);
+
+int __vdso_riscv_hwprobe(struct riscv_hwprobe *pairs, size_t pair_count,
+			 size_t cpu_count, unsigned long *cpus,
+			 unsigned int flags)
+{
+	const struct vdso_data *vd = __arch_get_vdso_data();
+	const struct arch_vdso_data *avd = &vd->arch_data;
+	bool all_cpus = !cpu_count && !cpus;
+	struct riscv_hwprobe *p = pairs;
+	struct riscv_hwprobe *end = pairs + pair_count;
+
+	/*
+	 * Defer to the syscall for exotic requests. The vdso has answers
+	 * stashed away only for the "all cpus" case. If all CPUs are
+	 * homogeneous, then this function can handle requests for arbitrary
+	 * masks.
+	 */
+	if ((flags != 0) || (!all_cpus && !avd->homogeneous_cpus))
+		return riscv_hwprobe(pairs, pair_count, cpu_count, cpus, flags);
+
+	/* This is something we can handle, fill out the pairs. */
+	while (p < end) {
+		if (p->key <= RISCV_HWPROBE_MAX_KEY) {
+			p->value = avd->all_cpu_hwprobe_values[p->key];
+
+		} else {
+			p->key = -1;
+			p->value = 0;
+		}
+
+		p++;
+	}
+
+	return 0;
+}

arch/riscv/kernel/vdso/sys_hwprobe.S

@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2023 Rivos, Inc */
+
+#include <linux/linkage.h>
+#include <asm/unistd.h>
+
+.text
+ENTRY(riscv_hwprobe)
+	.cfi_startproc
+	li a7, __NR_riscv_hwprobe
+	ecall
+	ret
+
+	.cfi_endproc
+ENDPROC(riscv_hwprobe)

arch/riscv/kernel/vdso/vdso.lds.S

@@ -82,6 +82,9 @@ VERSION
 #endif
 		__vdso_getcpu;
 		__vdso_flush_icache;
+#ifndef COMPAT_VDSO
+		__vdso_riscv_hwprobe;
+#endif
 	local: *;
 	};
 }

arch/riscv/kernel/vmlinux.lds.S

@@ -27,9 +27,6 @@ ENTRY(_start)
 
 jiffies = jiffies_64;
 
-PECOFF_SECTION_ALIGNMENT = 0x1000;
-PECOFF_FILE_ALIGNMENT = 0x200;
-
 SECTIONS
 {
 	/* Beginning of code and text segment */
@@ -86,6 +83,14 @@ SECTIONS
 	/* Start of init data section */
 	__init_data_begin = .;
 	INIT_DATA_SECTION(16)
+
+	/* Those sections result from the compilation of kernel/pi/string.c */
+	.init.pidata : {
+		*(.init.srodata.cst8*)
+		*(.init__bug_table*)
+		*(.init.sdata*)
+	}
+
 	.init.bss : {
 		*(.init.bss)	/* from the EFI stub */
 	}
@@ -99,10 +104,6 @@ SECTIONS
 		*(.rel.dyn*)
 	}
 
-	.rela.dyn : {
-		*(.rela*)
-	}
-
 	__init_data_end = .;
 
 	. = ALIGN(8);
@@ -129,9 +130,28 @@ SECTIONS
 		*(.sdata*)
 	}
 
+	.rela.dyn : ALIGN(8) {
+		__rela_dyn_start = .;
+		*(.rela .rela*)
+		__rela_dyn_end = .;
+	}
+
+	.got : { *(.got*) }
+
+#ifdef CONFIG_RELOCATABLE
+	.data.rel : { *(.data.rel*) }
+	.plt : { *(.plt) }
+	.dynamic : { *(.dynamic) }
+	.dynsym : { *(.dynsym) }
+	.dynstr : { *(.dynstr) }
+	.hash : { *(.hash) }
+	.gnu.hash : { *(.gnu.hash) }
+#endif
+
 #ifdef CONFIG_EFI
 	.pecoff_edata_padding : { BYTE(0); . = ALIGN(PECOFF_FILE_ALIGNMENT); }
 	__pecoff_data_raw_size = ABSOLUTE(. - __pecoff_text_end);
+	__pecoff_data_raw_end = ABSOLUTE(.);
 #endif
 
 	/* End of data section */
@@ -142,6 +162,7 @@ SECTIONS
 #ifdef CONFIG_EFI
 	. = ALIGN(PECOFF_SECTION_ALIGNMENT);
 	__pecoff_data_virt_size = ABSOLUTE(. - __pecoff_text_end);
+	__pecoff_data_virt_end = ABSOLUTE(.);
 #endif
 	_end = .;
 

arch/riscv/kvm/vcpu.c

@@ -63,6 +63,7 @@ static const unsigned long kvm_isa_ext_arr[] = {
 	KVM_ISA_EXT_ARR(SVPBMT),
 	KVM_ISA_EXT_ARR(ZIHINTPAUSE),
 	KVM_ISA_EXT_ARR(ZICBOM),
+	KVM_ISA_EXT_ARR(ZICBOZ),
 };
 
 static unsigned long kvm_riscv_vcpu_base2isa_ext(unsigned long base_ext)
@@ -283,6 +284,11 @@ static int kvm_riscv_vcpu_get_reg_config(struct kvm_vcpu *vcpu,
 			return -EINVAL;
 		reg_val = riscv_cbom_block_size;
 		break;
+	case KVM_REG_RISCV_CONFIG_REG(zicboz_block_size):
+		if (!riscv_isa_extension_available(vcpu->arch.isa, ZICBOZ))
+			return -EINVAL;
+		reg_val = riscv_cboz_block_size;
+		break;
 	case KVM_REG_RISCV_CONFIG_REG(mvendorid):
 		reg_val = vcpu->arch.mvendorid;
 		break;
@@ -354,6 +360,8 @@ static int kvm_riscv_vcpu_set_reg_config(struct kvm_vcpu *vcpu,
 		break;
 	case KVM_REG_RISCV_CONFIG_REG(zicbom_block_size):
 		return -EOPNOTSUPP;
+	case KVM_REG_RISCV_CONFIG_REG(zicboz_block_size):
+		return -EOPNOTSUPP;
 	case KVM_REG_RISCV_CONFIG_REG(mvendorid):
 		if (!vcpu->arch.ran_atleast_once)
 			vcpu->arch.mvendorid = reg_val;
@@ -865,6 +873,9 @@ static void kvm_riscv_vcpu_update_config(const unsigned long *isa)
 	if (riscv_isa_extension_available(isa, ZICBOM))
 		henvcfg |= (ENVCFG_CBIE | ENVCFG_CBCFE);
 
+	if (riscv_isa_extension_available(isa, ZICBOZ))
+		henvcfg |= ENVCFG_CBZE;
+
 	csr_write(CSR_HENVCFG, henvcfg);
 #ifdef CONFIG_32BIT
 	csr_write(CSR_HENVCFGH, henvcfg >> 32);

arch/riscv/lib/Makefile

@@ -8,5 +8,6 @@ lib-y			+= strlen.o
 lib-y			+= strncmp.o
 lib-$(CONFIG_MMU)	+= uaccess.o
 lib-$(CONFIG_64BIT)	+= tishift.o
+lib-$(CONFIG_RISCV_ISA_ZICBOZ)	+= clear_page.o
 
 obj-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o

arch/riscv/lib/clear_page.S

@@ -0,0 +1,74 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2023 Ventana Micro Systems Inc.
+ */
+
+#include <linux/linkage.h>
+#include <asm/asm.h>
+#include <asm/alternative-macros.h>
+#include <asm-generic/export.h>
+#include <asm/hwcap.h>
+#include <asm/insn-def.h>
+#include <asm/page.h>
+
+#define CBOZ_ALT(order, old, new)				\
+	ALTERNATIVE(old, new, 0,				\
+		    ((order) << 16) | RISCV_ISA_EXT_ZICBOZ,	\
+		    CONFIG_RISCV_ISA_ZICBOZ)
+
+/* void clear_page(void *page) */
+SYM_FUNC_START(clear_page)
+	li	a2, PAGE_SIZE
+
+	/*
+	 * If Zicboz isn't present, or somehow has a block
+	 * size larger than 4K, then fallback to memset.
+	 */
+	CBOZ_ALT(12, "j .Lno_zicboz", "nop")
+
+	lw	a1, riscv_cboz_block_size
+	add	a2, a0, a2
+.Lzero_loop:
+	CBO_zero(a0)
+	add	a0, a0, a1
+	CBOZ_ALT(11, "bltu a0, a2, .Lzero_loop; ret", "nop; nop")
+	CBO_zero(a0)
+	add	a0, a0, a1
+	CBOZ_ALT(10, "bltu a0, a2, .Lzero_loop; ret", "nop; nop")
+	CBO_zero(a0)
+	add	a0, a0, a1
+	CBO_zero(a0)
+	add	a0, a0, a1
+	CBOZ_ALT(9, "bltu a0, a2, .Lzero_loop; ret", "nop; nop")
+	CBO_zero(a0)
+	add	a0, a0, a1
+	CBO_zero(a0)
+	add	a0, a0, a1
+	CBO_zero(a0)
+	add	a0, a0, a1
+	CBO_zero(a0)
+	add	a0, a0, a1
+	CBOZ_ALT(8, "bltu a0, a2, .Lzero_loop; ret", "nop; nop")
+	CBO_zero(a0)
+	add	a0, a0, a1
+	CBO_zero(a0)
+	add	a0, a0, a1
+	CBO_zero(a0)
+	add	a0, a0, a1
+	CBO_zero(a0)
+	add	a0, a0, a1
+	CBO_zero(a0)
+	add	a0, a0, a1
+	CBO_zero(a0)
+	add	a0, a0, a1
+	CBO_zero(a0)
+	add	a0, a0, a1
+	CBO_zero(a0)
+	add	a0, a0, a1
+	bltu	a0, a2, .Lzero_loop
+	ret
+.Lno_zicboz:
+	li	a1, 0
+	tail	__memset
+SYM_FUNC_END(clear_page)
+EXPORT_SYMBOL(clear_page)

arch/riscv/lib/memcpy.S

@@ -106,3 +106,5 @@ WEAK(memcpy)
 6:
 	ret
 END(__memcpy)
+SYM_FUNC_ALIAS(__pi_memcpy, __memcpy)
+SYM_FUNC_ALIAS(__pi___memcpy, __memcpy)

arch/riscv/lib/memmove.S

@@ -314,3 +314,5 @@ return_from_memmove:
 
 SYM_FUNC_END(memmove)
 SYM_FUNC_END(__memmove)
+SYM_FUNC_ALIAS(__pi_memmove, __memmove)
+SYM_FUNC_ALIAS(__pi___memmove, __memmove)

arch/riscv/lib/strcmp.S

@@ -2,9 +2,8 @@
 
 #include <linux/linkage.h>
 #include <asm/asm.h>
-#include <asm-generic/export.h>
 #include <asm/alternative-macros.h>
-#include <asm/errata_list.h>
+#include <asm/hwcap.h>
 
 /* int strcmp(const char *cs, const char *ct) */
 SYM_FUNC_START(strcmp)

arch/riscv/lib/strlen.S

@@ -2,9 +2,8 @@
 
 #include <linux/linkage.h>
 #include <asm/asm.h>
-#include <asm-generic/export.h>
 #include <asm/alternative-macros.h>
-#include <asm/errata_list.h>
+#include <asm/hwcap.h>
 
 /* int strlen(const char *s) */
 SYM_FUNC_START(strlen)
@@ -131,3 +130,4 @@ strlen_zbb:
 .option pop
 #endif
 SYM_FUNC_END(strlen)
+SYM_FUNC_ALIAS(__pi_strlen, strlen)

arch/riscv/lib/strncmp.S

@@ -2,9 +2,8 @@
 
 #include <linux/linkage.h>
 #include <asm/asm.h>
-#include <asm-generic/export.h>
 #include <asm/alternative-macros.h>
-#include <asm/errata_list.h>
+#include <asm/hwcap.h>
 
 /* int strncmp(const char *cs, const char *ct, size_t count) */
 SYM_FUNC_START(strncmp)

arch/riscv/mm/Makefile

@@ -1,6 +1,10 @@
 # SPDX-License-Identifier: GPL-2.0-only
 
 CFLAGS_init.o := -mcmodel=medany
+ifdef CONFIG_RELOCATABLE
+CFLAGS_init.o += -fno-pie
+endif
+
 ifdef CONFIG_FTRACE
 CFLAGS_REMOVE_init.o = $(CC_FLAGS_FTRACE)
 CFLAGS_REMOVE_cacheflush.o = $(CC_FLAGS_FTRACE)

arch/riscv/mm/cacheflush.c

@@ -101,36 +101,48 @@ void flush_icache_pte(pte_t pte)
 unsigned int riscv_cbom_block_size;
 EXPORT_SYMBOL_GPL(riscv_cbom_block_size);
 
-void riscv_init_cbom_blocksize(void)
+unsigned int riscv_cboz_block_size;
+EXPORT_SYMBOL_GPL(riscv_cboz_block_size);
+
+static void cbo_get_block_size(struct device_node *node,
+			       const char *name, u32 *block_size,
+			       unsigned long *first_hartid)
 {
+	unsigned long hartid;
+	u32 val;
+
+	if (riscv_of_processor_hartid(node, &hartid))
+		return;
+
+	if (of_property_read_u32(node, name, &val))
+		return;
+
+	if (!*block_size) {
+		*block_size = val;
+		*first_hartid = hartid;
+	} else if (*block_size != val) {
+		pr_warn("%s mismatched between harts %lu and %lu\n",
+			name, *first_hartid, hartid);
+	}
+}
+
+void riscv_init_cbo_blocksizes(void)
+{
+	unsigned long cbom_hartid, cboz_hartid;
+	u32 cbom_block_size = 0, cboz_block_size = 0;
 	struct device_node *node;
-	unsigned long cbom_hartid;
-	u32 val, probed_block_size;
-	int ret;
 
-	probed_block_size = 0;
 	for_each_of_cpu_node(node) {
-		unsigned long hartid;
-
-		ret = riscv_of_processor_hartid(node, &hartid);
-		if (ret)
-			continue;
-
-		/* set block-size for cbom extension if available */
-		ret = of_property_read_u32(node, "riscv,cbom-block-size", &val);
-		if (ret)
-			continue;
-
-		if (!probed_block_size) {
-			probed_block_size = val;
-			cbom_hartid = hartid;
-		} else {
-			if (probed_block_size != val)
-				pr_warn("cbom-block-size mismatched between harts %lu and %lu\n",
-					cbom_hartid, hartid);
-		}
+		/* set block-size for cbom and/or cboz extension if available */
+		cbo_get_block_size(node, "riscv,cbom-block-size",
+				   &cbom_block_size, &cbom_hartid);
+		cbo_get_block_size(node, "riscv,cboz-block-size",
+				   &cboz_block_size, &cboz_hartid);
 	}
 
-	if (probed_block_size)
-		riscv_cbom_block_size = probed_block_size;
+	if (cbom_block_size)
+		riscv_cbom_block_size = cbom_block_size;
+
+	if (cboz_block_size)
+		riscv_cboz_block_size = cboz_block_size;
 }

arch/riscv/mm/fault.c

@@ -15,6 +15,7 @@
 #include <linux/uaccess.h>
 #include <linux/kprobes.h>
 #include <linux/kfence.h>
+#include <linux/entry-common.h>
 
 #include <asm/ptrace.h>
 #include <asm/tlbflush.h>
@@ -209,7 +210,7 @@ static inline bool access_error(unsigned long cause, struct vm_area_struct *vma)
  * This routine handles page faults.  It determines the address and the
  * problem, and then passes it off to one of the appropriate routines.
  */
-asmlinkage void do_page_fault(struct pt_regs *regs)
+void handle_page_fault(struct pt_regs *regs)
 {
 	struct task_struct *tsk;
 	struct vm_area_struct *vma;
@@ -256,7 +257,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs)
 	}
 #endif
 	/* Enable interrupts if they were enabled in the parent context. */
-	if (likely(regs->status & SR_PIE))
+	if (!regs_irqs_disabled(regs))
 		local_irq_enable();
 
 	/*
@@ -361,4 +362,3 @@ good_area:
 	}
 	return;
 }
-NOKPROBE_SYMBOL(do_page_fault);

arch/riscv/mm/hugetlbpage.c

@@ -2,6 +2,305 @@
 #include <linux/hugetlb.h>
 #include <linux/err.h>
 
+#ifdef CONFIG_RISCV_ISA_SVNAPOT
+pte_t *huge_pte_alloc(struct mm_struct *mm,
+		      struct vm_area_struct *vma,
+		      unsigned long addr,
+		      unsigned long sz)
+{
+	unsigned long order;
+	pte_t *pte = NULL;
+	pgd_t *pgd;
+	p4d_t *p4d;
+	pud_t *pud;
+	pmd_t *pmd;
+
+	pgd = pgd_offset(mm, addr);
+	p4d = p4d_alloc(mm, pgd, addr);
+	if (!p4d)
+		return NULL;
+
+	pud = pud_alloc(mm, p4d, addr);
+	if (!pud)
+		return NULL;
+
+	if (sz == PUD_SIZE) {
+		pte = (pte_t *)pud;
+		goto out;
+	}
+
+	if (sz == PMD_SIZE) {
+		if (want_pmd_share(vma, addr) && pud_none(*pud))
+			pte = huge_pmd_share(mm, vma, addr, pud);
+		else
+			pte = (pte_t *)pmd_alloc(mm, pud, addr);
+		goto out;
+	}
+
+	pmd = pmd_alloc(mm, pud, addr);
+	if (!pmd)
+		return NULL;
+
+	for_each_napot_order(order) {
+		if (napot_cont_size(order) == sz) {
+			pte = pte_alloc_map(mm, pmd, addr & napot_cont_mask(order));
+			break;
+		}
+	}
+
+out:
+	WARN_ON_ONCE(pte && pte_present(*pte) && !pte_huge(*pte));
+	return pte;
+}
+
+pte_t *huge_pte_offset(struct mm_struct *mm,
+		       unsigned long addr,
+		       unsigned long sz)
+{
+	unsigned long order;
+	pte_t *pte = NULL;
+	pgd_t *pgd;
+	p4d_t *p4d;
+	pud_t *pud;
+	pmd_t *pmd;
+
+	pgd = pgd_offset(mm, addr);
+	if (!pgd_present(*pgd))
+		return NULL;
+
+	p4d = p4d_offset(pgd, addr);
+	if (!p4d_present(*p4d))
+		return NULL;
+
+	pud = pud_offset(p4d, addr);
+	if (sz == PUD_SIZE)
+		/* must be pud huge, non-present or none */
+		return (pte_t *)pud;
+
+	if (!pud_present(*pud))
+		return NULL;
+
+	pmd = pmd_offset(pud, addr);
+	if (sz == PMD_SIZE)
+		/* must be pmd huge, non-present or none */
+		return (pte_t *)pmd;
+
+	if (!pmd_present(*pmd))
+		return NULL;
+
+	for_each_napot_order(order) {
+		if (napot_cont_size(order) == sz) {
+			pte = pte_offset_kernel(pmd, addr & napot_cont_mask(order));
+			break;
+		}
+	}
+	return pte;
+}
+
+static pte_t get_clear_contig(struct mm_struct *mm,
+			      unsigned long addr,
+			      pte_t *ptep,
+			      unsigned long pte_num)
+{
+	pte_t orig_pte = ptep_get(ptep);
+	unsigned long i;
+
+	for (i = 0; i < pte_num; i++, addr += PAGE_SIZE, ptep++) {
+		pte_t pte = ptep_get_and_clear(mm, addr, ptep);
+
+		if (pte_dirty(pte))
+			orig_pte = pte_mkdirty(orig_pte);
+
+		if (pte_young(pte))
+			orig_pte = pte_mkyoung(orig_pte);
+	}
+
+	return orig_pte;
+}
+
+static pte_t get_clear_contig_flush(struct mm_struct *mm,
+				    unsigned long addr,
+				    pte_t *ptep,
+				    unsigned long pte_num)
+{
+	pte_t orig_pte = get_clear_contig(mm, addr, ptep, pte_num);
+	struct vm_area_struct vma = TLB_FLUSH_VMA(mm, 0);
+	bool valid = !pte_none(orig_pte);
+
+	if (valid)
+		flush_tlb_range(&vma, addr, addr + (PAGE_SIZE * pte_num));
+
+	return orig_pte;
+}
+
+pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, vm_flags_t flags)
+{
+	unsigned long order;
+
+	for_each_napot_order(order) {
+		if (shift == napot_cont_shift(order)) {
+			entry = pte_mknapot(entry, order);
+			break;
+		}
+	}
+	if (order == NAPOT_ORDER_MAX)
+		entry = pte_mkhuge(entry);
+
+	return entry;
+}
+
+void set_huge_pte_at(struct mm_struct *mm,
+		     unsigned long addr,
+		     pte_t *ptep,
+		     pte_t pte)
+{
+	int i, pte_num;
+
+	if (!pte_napot(pte)) {
+		set_pte_at(mm, addr, ptep, pte);
+		return;
+	}
+
+	pte_num = napot_pte_num(napot_cont_order(pte));
+	for (i = 0; i < pte_num; i++, ptep++, addr += PAGE_SIZE)
+		set_pte_at(mm, addr, ptep, pte);
+}
+
+int huge_ptep_set_access_flags(struct vm_area_struct *vma,
+			       unsigned long addr,
+			       pte_t *ptep,
+			       pte_t pte,
+			       int dirty)
+{
+	struct mm_struct *mm = vma->vm_mm;
+	unsigned long order;
+	pte_t orig_pte;
+	int i, pte_num;
+
+	if (!pte_napot(pte))
+		return ptep_set_access_flags(vma, addr, ptep, pte, dirty);
+
+	order = napot_cont_order(pte);
+	pte_num = napot_pte_num(order);
+	ptep = huge_pte_offset(mm, addr, napot_cont_size(order));
+	orig_pte = get_clear_contig_flush(mm, addr, ptep, pte_num);
+
+	if (pte_dirty(orig_pte))
+		pte = pte_mkdirty(pte);
+
+	if (pte_young(orig_pte))
+		pte = pte_mkyoung(pte);
+
+	for (i = 0; i < pte_num; i++, addr += PAGE_SIZE, ptep++)
+		set_pte_at(mm, addr, ptep, pte);
+
+	return true;
+}
+
+pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
+			      unsigned long addr,
+			      pte_t *ptep)
+{
+	pte_t orig_pte = ptep_get(ptep);
+	int pte_num;
+
+	if (!pte_napot(orig_pte))
+		return ptep_get_and_clear(mm, addr, ptep);
+
+	pte_num = napot_pte_num(napot_cont_order(orig_pte));
+
+	return get_clear_contig(mm, addr, ptep, pte_num);
+}
+
+void huge_ptep_set_wrprotect(struct mm_struct *mm,
+			     unsigned long addr,
+			     pte_t *ptep)
+{
+	pte_t pte = ptep_get(ptep);
+	unsigned long order;
+	int i, pte_num;
+
+	if (!pte_napot(pte)) {
+		ptep_set_wrprotect(mm, addr, ptep);
+		return;
+	}
+
+	order = napot_cont_order(pte);
+	pte_num = napot_pte_num(order);
+	ptep = huge_pte_offset(mm, addr, napot_cont_size(order));
+
+	for (i = 0; i < pte_num; i++, addr += PAGE_SIZE, ptep++)
+		ptep_set_wrprotect(mm, addr, ptep);
+}
+
+pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
+			    unsigned long addr,
+			    pte_t *ptep)
+{
+	pte_t pte = ptep_get(ptep);
+	int pte_num;
+
+	if (!pte_napot(pte))
+		return ptep_clear_flush(vma, addr, ptep);
+
+	pte_num = napot_pte_num(napot_cont_order(pte));
+
+	return get_clear_contig_flush(vma->vm_mm, addr, ptep, pte_num);
+}
+
+void huge_pte_clear(struct mm_struct *mm,
+		    unsigned long addr,
+		    pte_t *ptep,
+		    unsigned long sz)
+{
+	pte_t pte = READ_ONCE(*ptep);
+	int i, pte_num;
+
+	if (!pte_napot(pte)) {
+		pte_clear(mm, addr, ptep);
+		return;
+	}
+
+	pte_num = napot_pte_num(napot_cont_order(pte));
+	for (i = 0; i < pte_num; i++, addr += PAGE_SIZE, ptep++)
+		pte_clear(mm, addr, ptep);
+}
+
+static __init bool is_napot_size(unsigned long size)
+{
+	unsigned long order;
+
+	if (!has_svnapot())
+		return false;
+
+	for_each_napot_order(order) {
+		if (size == napot_cont_size(order))
+			return true;
+	}
+	return false;
+}
+
+static __init int napot_hugetlbpages_init(void)
+{
+	if (has_svnapot()) {
+		unsigned long order;
+
+		for_each_napot_order(order)
+			hugetlb_add_hstate(order);
+	}
+	return 0;
+}
+arch_initcall(napot_hugetlbpages_init);
+
+#else
+
+static __init bool is_napot_size(unsigned long size)
+{
+	return false;
+}
+
+#endif /*CONFIG_RISCV_ISA_SVNAPOT*/
+
 int pud_huge(pud_t pud)
 {
 	return pud_leaf(pud);
@@ -18,6 +317,8 @@ bool __init arch_hugetlb_valid_size(unsigned long size)
 		return true;
 	else if (IS_ENABLED(CONFIG_64BIT) && size == PUD_SIZE)
 		return true;
+	else if (is_napot_size(size))
+		return true;
 	else
 		return false;
 }

arch/riscv/mm/init.c

@@ -20,6 +20,9 @@
 #include <linux/dma-map-ops.h>
 #include <linux/crash_dump.h>
 #include <linux/hugetlb.h>
+#ifdef CONFIG_RELOCATABLE
+#include <linux/elf.h>
+#endif
 
 #include <asm/fixmap.h>
 #include <asm/tlbflush.h>
@@ -145,7 +148,7 @@ static void __init print_vm_layout(void)
 		print_ml("kasan", KASAN_SHADOW_START, KASAN_SHADOW_END);
 #endif
 
-		print_ml("kernel", (unsigned long)KERNEL_LINK_ADDR,
+		print_ml("kernel", (unsigned long)kernel_map.virt_addr,
 			 (unsigned long)ADDRESS_SPACE_END);
 	}
 }
@@ -212,6 +215,14 @@ static void __init setup_bootmem(void)
 	phys_ram_end = memblock_end_of_DRAM();
 	if (!IS_ENABLED(CONFIG_XIP_KERNEL))
 		phys_ram_base = memblock_start_of_DRAM();
+
+	/*
+	 * In 64-bit, any use of __va/__pa before this point is wrong as we
+	 * did not know the start of DRAM before.
+	 */
+	if (IS_ENABLED(CONFIG_64BIT))
+		kernel_map.va_pa_offset = PAGE_OFFSET - phys_ram_base;
+
 	/*
 	 * memblock allocator is not aware of the fact that last 4K bytes of
 	 * the addressable memory can not be mapped because of IS_ERR_VALUE
@@ -261,9 +272,6 @@ static void __init setup_bootmem(void)
 #ifdef CONFIG_MMU
 struct pt_alloc_ops pt_ops __initdata;
 
-unsigned long riscv_pfn_base __ro_after_init;
-EXPORT_SYMBOL(riscv_pfn_base);
-
 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
 static pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
@@ -272,7 +280,6 @@ pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
 
 #ifdef CONFIG_XIP_KERNEL
 #define pt_ops			(*(struct pt_alloc_ops *)XIP_FIXUP(&pt_ops))
-#define riscv_pfn_base         (*(unsigned long  *)XIP_FIXUP(&riscv_pfn_base))
 #define trampoline_pg_dir      ((pgd_t *)XIP_FIXUP(trampoline_pg_dir))
 #define fixmap_pte             ((pte_t *)XIP_FIXUP(fixmap_pte))
 #define early_pg_dir           ((pgd_t *)XIP_FIXUP(early_pg_dir))
@@ -654,9 +661,16 @@ void __init create_pgd_mapping(pgd_t *pgdp,
 
 static uintptr_t __init best_map_size(phys_addr_t base, phys_addr_t size)
 {
-	/* Upgrade to PMD_SIZE mappings whenever possible */
-	base &= PMD_SIZE - 1;
-	if (!base && size >= PMD_SIZE)
+	if (!(base & (PGDIR_SIZE - 1)) && size >= PGDIR_SIZE)
+		return PGDIR_SIZE;
+
+	if (!(base & (P4D_SIZE - 1)) && size >= P4D_SIZE)
+		return P4D_SIZE;
+
+	if (!(base & (PUD_SIZE - 1)) && size >= PUD_SIZE)
+		return PUD_SIZE;
+
+	if (!(base & (PMD_SIZE - 1)) && size >= PMD_SIZE)
 		return PMD_SIZE;
 
 	return PAGE_SIZE;
@@ -715,6 +729,8 @@ static __init pgprot_t pgprot_from_va(uintptr_t va)
 #endif /* CONFIG_STRICT_KERNEL_RWX */
 
 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
+u64 __pi_set_satp_mode_from_cmdline(uintptr_t dtb_pa);
+
 static void __init disable_pgtable_l5(void)
 {
 	pgtable_l5_enabled = false;
@@ -729,17 +745,39 @@ static void __init disable_pgtable_l4(void)
 	satp_mode = SATP_MODE_39;
 }
 
+static int __init print_no4lvl(char *p)
+{
+	pr_info("Disabled 4-level and 5-level paging");
+	return 0;
+}
+early_param("no4lvl", print_no4lvl);
+
+static int __init print_no5lvl(char *p)
+{
+	pr_info("Disabled 5-level paging");
+	return 0;
+}
+early_param("no5lvl", print_no5lvl);
+
 /*
  * There is a simple way to determine if 4-level is supported by the
  * underlying hardware: establish 1:1 mapping in 4-level page table mode
  * then read SATP to see if the configuration was taken into account
  * meaning sv48 is supported.
  */
-static __init void set_satp_mode(void)
+static __init void set_satp_mode(uintptr_t dtb_pa)
 {
 	u64 identity_satp, hw_satp;
 	uintptr_t set_satp_mode_pmd = ((unsigned long)set_satp_mode) & PMD_MASK;
-	bool check_l4 = false;
+	u64 satp_mode_cmdline = __pi_set_satp_mode_from_cmdline(dtb_pa);
+
+	if (satp_mode_cmdline == SATP_MODE_57) {
+		disable_pgtable_l5();
+	} else if (satp_mode_cmdline == SATP_MODE_48) {
+		disable_pgtable_l5();
+		disable_pgtable_l4();
+		return;
+	}
 
 	create_p4d_mapping(early_p4d,
 			set_satp_mode_pmd, (uintptr_t)early_pud,
@@ -758,7 +796,8 @@ static __init void set_satp_mode(void)
 retry:
 	create_pgd_mapping(early_pg_dir,
 			   set_satp_mode_pmd,
-			   check_l4 ? (uintptr_t)early_pud : (uintptr_t)early_p4d,
+			   pgtable_l5_enabled ?
+				(uintptr_t)early_p4d : (uintptr_t)early_pud,
 			   PGDIR_SIZE, PAGE_TABLE);
 
 	identity_satp = PFN_DOWN((uintptr_t)&early_pg_dir) | satp_mode;
@@ -769,9 +808,8 @@ retry:
 	local_flush_tlb_all();
 
 	if (hw_satp != identity_satp) {
-		if (!check_l4) {
+		if (pgtable_l5_enabled) {
 			disable_pgtable_l5();
-			check_l4 = true;
 			memset(early_pg_dir, 0, PAGE_SIZE);
 			goto retry;
 		}
@@ -803,6 +841,44 @@ retry:
 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing."
 #endif
 
+#ifdef CONFIG_RELOCATABLE
+extern unsigned long __rela_dyn_start, __rela_dyn_end;
+
+static void __init relocate_kernel(void)
+{
+	Elf64_Rela *rela = (Elf64_Rela *)&__rela_dyn_start;
+	/*
+	 * This holds the offset between the linked virtual address and the
+	 * relocated virtual address.
+	 */
+	uintptr_t reloc_offset = kernel_map.virt_addr - KERNEL_LINK_ADDR;
+	/*
+	 * This holds the offset between kernel linked virtual address and
+	 * physical address.
+	 */
+	uintptr_t va_kernel_link_pa_offset = KERNEL_LINK_ADDR - kernel_map.phys_addr;
+
+	for ( ; rela < (Elf64_Rela *)&__rela_dyn_end; rela++) {
+		Elf64_Addr addr = (rela->r_offset - va_kernel_link_pa_offset);
+		Elf64_Addr relocated_addr = rela->r_addend;
+
+		if (rela->r_info != R_RISCV_RELATIVE)
+			continue;
+
+		/*
+		 * Make sure to not relocate vdso symbols like rt_sigreturn
+		 * which are linked from the address 0 in vmlinux since
+		 * vdso symbol addresses are actually used as an offset from
+		 * mm->context.vdso in VDSO_OFFSET macro.
+		 */
+		if (relocated_addr >= KERNEL_LINK_ADDR)
+			relocated_addr += reloc_offset;
+
+		*(Elf64_Addr *)addr = relocated_addr;
+	}
+}
+#endif /* CONFIG_RELOCATABLE */
+
 #ifdef CONFIG_XIP_KERNEL
 static void __init create_kernel_page_table(pgd_t *pgdir,
 					    __always_unused bool early)
@@ -958,14 +1034,25 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
 #endif
 
 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
-	set_satp_mode();
+	set_satp_mode(dtb_pa);
 #endif
 
-	kernel_map.va_pa_offset = PAGE_OFFSET - kernel_map.phys_addr;
+	/*
+	 * In 64-bit, we defer the setup of va_pa_offset to setup_bootmem,
+	 * where we have the system memory layout: this allows us to align
+	 * the physical and virtual mappings and then make use of PUD/P4D/PGD
+	 * for the linear mapping. This is only possible because the kernel
+	 * mapping lies outside the linear mapping.
+	 * In 32-bit however, as the kernel resides in the linear mapping,
+	 * setup_vm_final can not change the mapping established here,
+	 * otherwise the same kernel addresses would get mapped to different
+	 * physical addresses (if the start of dram is different from the
+	 * kernel physical address start).
+	 */
+	kernel_map.va_pa_offset = IS_ENABLED(CONFIG_64BIT) ?
+				0UL : PAGE_OFFSET - kernel_map.phys_addr;
 	kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr;
 
-	riscv_pfn_base = PFN_DOWN(kernel_map.phys_addr);
-
 	/*
 	 * The default maximal physical memory size is KERN_VIRT_SIZE for 32-bit
 	 * kernel, whereas for 64-bit kernel, the end of the virtual address
@@ -986,6 +1073,17 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
 	BUG_ON((kernel_map.virt_addr + kernel_map.size) > ADDRESS_SPACE_END - SZ_4K);
 #endif
 
+#ifdef CONFIG_RELOCATABLE
+	/*
+	 * Early page table uses only one PUD, which makes it possible
+	 * to map PUD_SIZE aligned on PUD_SIZE: if the relocation offset
+	 * makes the kernel cross over a PUD_SIZE boundary, raise a bug
+	 * since a part of the kernel would not get mapped.
+	 */
+	BUG_ON(PUD_SIZE - (kernel_map.virt_addr & (PUD_SIZE - 1)) < kernel_map.size);
+	relocate_kernel();
+#endif
+
 	apply_early_boot_alternatives();
 	pt_ops_set_early();
 
@@ -1070,12 +1168,62 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
 	pt_ops_set_fixmap();
 }
 
-static void __init setup_vm_final(void)
+static void __init create_linear_mapping_range(phys_addr_t start,
+					       phys_addr_t end)
 {
+	phys_addr_t pa;
 	uintptr_t va, map_size;
-	phys_addr_t pa, start, end;
+
+	for (pa = start; pa < end; pa += map_size) {
+		va = (uintptr_t)__va(pa);
+		map_size = best_map_size(pa, end - pa);
+
+		create_pgd_mapping(swapper_pg_dir, va, pa, map_size,
+				   pgprot_from_va(va));
+	}
+}
+
+static void __init create_linear_mapping_page_table(void)
+{
+	phys_addr_t start, end;
 	u64 i;
 
+#ifdef CONFIG_STRICT_KERNEL_RWX
+	phys_addr_t ktext_start = __pa_symbol(_start);
+	phys_addr_t ktext_size = __init_data_begin - _start;
+	phys_addr_t krodata_start = __pa_symbol(__start_rodata);
+	phys_addr_t krodata_size = _data - __start_rodata;
+
+	/* Isolate kernel text and rodata so they don't get mapped with a PUD */
+	memblock_mark_nomap(ktext_start,  ktext_size);
+	memblock_mark_nomap(krodata_start, krodata_size);
+#endif
+
+	/* Map all memory banks in the linear mapping */
+	for_each_mem_range(i, &start, &end) {
+		if (start >= end)
+			break;
+		if (start <= __pa(PAGE_OFFSET) &&
+		    __pa(PAGE_OFFSET) < end)
+			start = __pa(PAGE_OFFSET);
+		if (end >= __pa(PAGE_OFFSET) + memory_limit)
+			end = __pa(PAGE_OFFSET) + memory_limit;
+
+		create_linear_mapping_range(start, end);
+	}
+
+#ifdef CONFIG_STRICT_KERNEL_RWX
+	create_linear_mapping_range(ktext_start, ktext_start + ktext_size);
+	create_linear_mapping_range(krodata_start,
+				    krodata_start + krodata_size);
+
+	memblock_clear_nomap(ktext_start,  ktext_size);
+	memblock_clear_nomap(krodata_start, krodata_size);
+#endif
+}
+
+static void __init setup_vm_final(void)
+{
 	/* Setup swapper PGD for fixmap */
 #if !defined(CONFIG_64BIT)
 	/*
@@ -1091,24 +1239,8 @@ static void __init setup_vm_final(void)
 			   __pa_symbol(fixmap_pgd_next),
 			   PGDIR_SIZE, PAGE_TABLE);
 
-	/* Map all memory banks in the linear mapping */
-	for_each_mem_range(i, &start, &end) {
-		if (start >= end)
-			break;
-		if (start <= __pa(PAGE_OFFSET) &&
-		    __pa(PAGE_OFFSET) < end)
-			start = __pa(PAGE_OFFSET);
-		if (end >= __pa(PAGE_OFFSET) + memory_limit)
-			end = __pa(PAGE_OFFSET) + memory_limit;
-
-		for (pa = start; pa < end; pa += map_size) {
-			va = (uintptr_t)__va(pa);
-			map_size = best_map_size(pa, end - pa);
-
-			create_pgd_mapping(swapper_pg_dir, va, pa, map_size,
-					   pgprot_from_va(va));
-		}
-	}
+	/* Map the linear mapping */
+	create_linear_mapping_page_table();
 
 	/* Map the kernel */
 	if (IS_ENABLED(CONFIG_64BIT))

arch/riscv/mm/kasan_init.c

@@ -18,58 +18,48 @@
  * For sv39, the region is aligned on PGDIR_SIZE so we only need to populate
  * the page global directory with kasan_early_shadow_pmd.
  *
- * For sv48 and sv57, the region is not aligned on PGDIR_SIZE so the mapping
- * must be divided as follows:
- * - the first PGD entry, although incomplete, is populated with
- *   kasan_early_shadow_pud/p4d
- * - the PGD entries in the middle are populated with kasan_early_shadow_pud/p4d
- * - the last PGD entry is shared with the kernel mapping so populated at the
- *   lower levels pud/p4d
- *
- * In addition, when shallow populating a kasan region (for example vmalloc),
- * this region may also not be aligned on PGDIR size, so we must go down to the
- * pud level too.
+ * For sv48 and sv57, the region start is aligned on PGDIR_SIZE whereas the end
+ * region is not and then we have to go down to the PUD level.
  */
 
 extern pgd_t early_pg_dir[PTRS_PER_PGD];
+pgd_t tmp_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
+p4d_t tmp_p4d[PTRS_PER_P4D] __page_aligned_bss;
+pud_t tmp_pud[PTRS_PER_PUD] __page_aligned_bss;
 
 static void __init kasan_populate_pte(pmd_t *pmd, unsigned long vaddr, unsigned long end)
 {
 	phys_addr_t phys_addr;
-	pte_t *ptep, *base_pte;
+	pte_t *ptep, *p;
 
-	if (pmd_none(*pmd))
-		base_pte = memblock_alloc(PTRS_PER_PTE * sizeof(pte_t), PAGE_SIZE);
-	else
-		base_pte = (pte_t *)pmd_page_vaddr(*pmd);
+	if (pmd_none(*pmd)) {
+		p = memblock_alloc(PTRS_PER_PTE * sizeof(pte_t), PAGE_SIZE);
+		set_pmd(pmd, pfn_pmd(PFN_DOWN(__pa(p)), PAGE_TABLE));
+	}
 
-	ptep = base_pte + pte_index(vaddr);
+	ptep = pte_offset_kernel(pmd, vaddr);
 
 	do {
 		if (pte_none(*ptep)) {
 			phys_addr = memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
 			set_pte(ptep, pfn_pte(PFN_DOWN(phys_addr), PAGE_KERNEL));
+			memset(__va(phys_addr), KASAN_SHADOW_INIT, PAGE_SIZE);
 		}
 	} while (ptep++, vaddr += PAGE_SIZE, vaddr != end);
-
-	set_pmd(pmd, pfn_pmd(PFN_DOWN(__pa(base_pte)), PAGE_TABLE));
 }
 
 static void __init kasan_populate_pmd(pud_t *pud, unsigned long vaddr, unsigned long end)
 {
 	phys_addr_t phys_addr;
-	pmd_t *pmdp, *base_pmd;
+	pmd_t *pmdp, *p;
 	unsigned long next;
 
 	if (pud_none(*pud)) {
-		base_pmd = memblock_alloc(PTRS_PER_PMD * sizeof(pmd_t), PAGE_SIZE);
-	} else {
-		base_pmd = (pmd_t *)pud_pgtable(*pud);
-		if (base_pmd == lm_alias(kasan_early_shadow_pmd))
-			base_pmd = memblock_alloc(PTRS_PER_PMD * sizeof(pmd_t), PAGE_SIZE);
+		p = memblock_alloc(PTRS_PER_PMD * sizeof(pmd_t), PAGE_SIZE);
+		set_pud(pud, pfn_pud(PFN_DOWN(__pa(p)), PAGE_TABLE));
 	}
 
-	pmdp = base_pmd + pmd_index(vaddr);
+	pmdp = pmd_offset(pud, vaddr);
 
 	do {
 		next = pmd_addr_end(vaddr, end);
@@ -78,157 +68,77 @@ static void __init kasan_populate_pmd(pud_t *pud, unsigned long vaddr, unsigned
 			phys_addr = memblock_phys_alloc(PMD_SIZE, PMD_SIZE);
 			if (phys_addr) {
 				set_pmd(pmdp, pfn_pmd(PFN_DOWN(phys_addr), PAGE_KERNEL));
+				memset(__va(phys_addr), KASAN_SHADOW_INIT, PMD_SIZE);
 				continue;
 			}
 		}
 
 		kasan_populate_pte(pmdp, vaddr, next);
 	} while (pmdp++, vaddr = next, vaddr != end);
-
-	/*
-	 * Wait for the whole PGD to be populated before setting the PGD in
-	 * the page table, otherwise, if we did set the PGD before populating
-	 * it entirely, memblock could allocate a page at a physical address
-	 * where KASAN is not populated yet and then we'd get a page fault.
-	 */
-	set_pud(pud, pfn_pud(PFN_DOWN(__pa(base_pmd)), PAGE_TABLE));
 }
 
-static void __init kasan_populate_pud(pgd_t *pgd,
-				      unsigned long vaddr, unsigned long end,
-				      bool early)
+static void __init kasan_populate_pud(p4d_t *p4d,
+				      unsigned long vaddr, unsigned long end)
 {
 	phys_addr_t phys_addr;
-	pud_t *pudp, *base_pud;
+	pud_t *pudp, *p;
 	unsigned long next;
 
-	if (early) {
-		/*
-		 * We can't use pgd_page_vaddr here as it would return a linear
-		 * mapping address but it is not mapped yet, but when populating
-		 * early_pg_dir, we need the physical address and when populating
-		 * swapper_pg_dir, we need the kernel virtual address so use
-		 * pt_ops facility.
-		 */
-		base_pud = pt_ops.get_pud_virt(pfn_to_phys(_pgd_pfn(*pgd)));
-	} else if (pgd_none(*pgd)) {
-		base_pud = memblock_alloc(PTRS_PER_PUD * sizeof(pud_t), PAGE_SIZE);
-		memcpy(base_pud, (void *)kasan_early_shadow_pud,
-			sizeof(pud_t) * PTRS_PER_PUD);
-	} else {
-		base_pud = (pud_t *)pgd_page_vaddr(*pgd);
-		if (base_pud == lm_alias(kasan_early_shadow_pud)) {
-			base_pud = memblock_alloc(PTRS_PER_PUD * sizeof(pud_t), PAGE_SIZE);
-			memcpy(base_pud, (void *)kasan_early_shadow_pud,
-			       sizeof(pud_t) * PTRS_PER_PUD);
-		}
+	if (p4d_none(*p4d)) {
+		p = memblock_alloc(PTRS_PER_PUD * sizeof(pud_t), PAGE_SIZE);
+		set_p4d(p4d, pfn_p4d(PFN_DOWN(__pa(p)), PAGE_TABLE));
 	}
 
-	pudp = base_pud + pud_index(vaddr);
+	pudp = pud_offset(p4d, vaddr);
 
 	do {
 		next = pud_addr_end(vaddr, end);
 
 		if (pud_none(*pudp) && IS_ALIGNED(vaddr, PUD_SIZE) && (next - vaddr) >= PUD_SIZE) {
-			if (early) {
-				phys_addr = __pa(((uintptr_t)kasan_early_shadow_pmd));
-				set_pud(pudp, pfn_pud(PFN_DOWN(phys_addr), PAGE_TABLE));
+			phys_addr = memblock_phys_alloc(PUD_SIZE, PUD_SIZE);
+			if (phys_addr) {
+				set_pud(pudp, pfn_pud(PFN_DOWN(phys_addr), PAGE_KERNEL));
+				memset(__va(phys_addr), KASAN_SHADOW_INIT, PUD_SIZE);
 				continue;
-			} else {
-				phys_addr = memblock_phys_alloc(PUD_SIZE, PUD_SIZE);
-				if (phys_addr) {
-					set_pud(pudp, pfn_pud(PFN_DOWN(phys_addr), PAGE_KERNEL));
-					continue;
-				}
 			}
 		}
 
 		kasan_populate_pmd(pudp, vaddr, next);
 	} while (pudp++, vaddr = next, vaddr != end);
-
-	/*
-	 * Wait for the whole PGD to be populated before setting the PGD in
-	 * the page table, otherwise, if we did set the PGD before populating
-	 * it entirely, memblock could allocate a page at a physical address
-	 * where KASAN is not populated yet and then we'd get a page fault.
-	 */
-	if (!early)
-		set_pgd(pgd, pfn_pgd(PFN_DOWN(__pa(base_pud)), PAGE_TABLE));
 }
 
 static void __init kasan_populate_p4d(pgd_t *pgd,
-				      unsigned long vaddr, unsigned long end,
-				      bool early)
+				      unsigned long vaddr, unsigned long end)
 {
 	phys_addr_t phys_addr;
-	p4d_t *p4dp, *base_p4d;
+	p4d_t *p4dp, *p;
 	unsigned long next;
 
-	if (early) {
-		/*
-		 * We can't use pgd_page_vaddr here as it would return a linear
-		 * mapping address but it is not mapped yet, but when populating
-		 * early_pg_dir, we need the physical address and when populating
-		 * swapper_pg_dir, we need the kernel virtual address so use
-		 * pt_ops facility.
-		 */
-		base_p4d = pt_ops.get_p4d_virt(pfn_to_phys(_pgd_pfn(*pgd)));
-	} else {
-		base_p4d = (p4d_t *)pgd_page_vaddr(*pgd);
-		if (base_p4d == lm_alias(kasan_early_shadow_p4d)) {
-			base_p4d = memblock_alloc(PTRS_PER_PUD * sizeof(p4d_t), PAGE_SIZE);
-			memcpy(base_p4d, (void *)kasan_early_shadow_p4d,
-				sizeof(p4d_t) * PTRS_PER_P4D);
-		}
+	if (pgd_none(*pgd)) {
+		p = memblock_alloc(PTRS_PER_P4D * sizeof(p4d_t), PAGE_SIZE);
+		set_pgd(pgd, pfn_pgd(PFN_DOWN(__pa(p)), PAGE_TABLE));
 	}
 
-	p4dp = base_p4d + p4d_index(vaddr);
+	p4dp = p4d_offset(pgd, vaddr);
 
 	do {
 		next = p4d_addr_end(vaddr, end);
 
 		if (p4d_none(*p4dp) && IS_ALIGNED(vaddr, P4D_SIZE) && (next - vaddr) >= P4D_SIZE) {
-			if (early) {
-				phys_addr = __pa(((uintptr_t)kasan_early_shadow_pud));
-				set_p4d(p4dp, pfn_p4d(PFN_DOWN(phys_addr), PAGE_TABLE));
+			phys_addr = memblock_phys_alloc(P4D_SIZE, P4D_SIZE);
+			if (phys_addr) {
+				set_p4d(p4dp, pfn_p4d(PFN_DOWN(phys_addr), PAGE_KERNEL));
+				memset(__va(phys_addr), KASAN_SHADOW_INIT, P4D_SIZE);
 				continue;
-			} else {
-				phys_addr = memblock_phys_alloc(P4D_SIZE, P4D_SIZE);
-				if (phys_addr) {
-					set_p4d(p4dp, pfn_p4d(PFN_DOWN(phys_addr), PAGE_KERNEL));
-					continue;
-				}
 			}
 		}
 
-		kasan_populate_pud((pgd_t *)p4dp, vaddr, next, early);
+		kasan_populate_pud(p4dp, vaddr, next);
 	} while (p4dp++, vaddr = next, vaddr != end);
-
-	/*
-	 * Wait for the whole P4D to be populated before setting the P4D in
-	 * the page table, otherwise, if we did set the P4D before populating
-	 * it entirely, memblock could allocate a page at a physical address
-	 * where KASAN is not populated yet and then we'd get a page fault.
-	 */
-	if (!early)
-		set_pgd(pgd, pfn_pgd(PFN_DOWN(__pa(base_p4d)), PAGE_TABLE));
 }
 
-#define kasan_early_shadow_pgd_next			(pgtable_l5_enabled ?	\
-				(uintptr_t)kasan_early_shadow_p4d :		\
-							(pgtable_l4_enabled ?	\
-				(uintptr_t)kasan_early_shadow_pud :		\
-				(uintptr_t)kasan_early_shadow_pmd))
-#define kasan_populate_pgd_next(pgdp, vaddr, next, early)			\
-		(pgtable_l5_enabled ?						\
-		kasan_populate_p4d(pgdp, vaddr, next, early) :			\
-		(pgtable_l4_enabled ?						\
-			kasan_populate_pud(pgdp, vaddr, next, early) :		\
-			kasan_populate_pmd((pud_t *)pgdp, vaddr, next)))
-
 static void __init kasan_populate_pgd(pgd_t *pgdp,
-				      unsigned long vaddr, unsigned long end,
-				      bool early)
+				      unsigned long vaddr, unsigned long end)
 {
 	phys_addr_t phys_addr;
 	unsigned long next;
@@ -236,29 +146,174 @@ static void __init kasan_populate_pgd(pgd_t *pgdp,
 	do {
 		next = pgd_addr_end(vaddr, end);
 
-		if (IS_ALIGNED(vaddr, PGDIR_SIZE) && (next - vaddr) >= PGDIR_SIZE) {
-			if (early) {
-				phys_addr = __pa((uintptr_t)kasan_early_shadow_pgd_next);
-				set_pgd(pgdp, pfn_pgd(PFN_DOWN(phys_addr), PAGE_TABLE));
+		if (pgd_none(*pgdp) && IS_ALIGNED(vaddr, PGDIR_SIZE) &&
+		    (next - vaddr) >= PGDIR_SIZE) {
+			phys_addr = memblock_phys_alloc(PGDIR_SIZE, PGDIR_SIZE);
+			if (phys_addr) {
+				set_pgd(pgdp, pfn_pgd(PFN_DOWN(phys_addr), PAGE_KERNEL));
+				memset(__va(phys_addr), KASAN_SHADOW_INIT, PGDIR_SIZE);
 				continue;
-			} else if (pgd_page_vaddr(*pgdp) ==
-				   (unsigned long)lm_alias(kasan_early_shadow_pgd_next)) {
-				/*
-				 * pgdp can't be none since kasan_early_init
-				 * initialized all KASAN shadow region with
-				 * kasan_early_shadow_pud: if this is still the
-				 * case, that means we can try to allocate a
-				 * hugepage as a replacement.
-				 */
-				phys_addr = memblock_phys_alloc(PGDIR_SIZE, PGDIR_SIZE);
-				if (phys_addr) {
-					set_pgd(pgdp, pfn_pgd(PFN_DOWN(phys_addr), PAGE_KERNEL));
-					continue;
-				}
 			}
 		}
 
-		kasan_populate_pgd_next(pgdp, vaddr, next, early);
+		kasan_populate_p4d(pgdp, vaddr, next);
+	} while (pgdp++, vaddr = next, vaddr != end);
+}
+
+static void __init kasan_early_clear_pud(p4d_t *p4dp,
+					 unsigned long vaddr, unsigned long end)
+{
+	pud_t *pudp, *base_pud;
+	unsigned long next;
+
+	if (!pgtable_l4_enabled) {
+		pudp = (pud_t *)p4dp;
+	} else {
+		base_pud = pt_ops.get_pud_virt(pfn_to_phys(_p4d_pfn(*p4dp)));
+		pudp = base_pud + pud_index(vaddr);
+	}
+
+	do {
+		next = pud_addr_end(vaddr, end);
+
+		if (IS_ALIGNED(vaddr, PUD_SIZE) && (next - vaddr) >= PUD_SIZE) {
+			pud_clear(pudp);
+			continue;
+		}
+
+		BUG();
+	} while (pudp++, vaddr = next, vaddr != end);
+}
+
+static void __init kasan_early_clear_p4d(pgd_t *pgdp,
+					 unsigned long vaddr, unsigned long end)
+{
+	p4d_t *p4dp, *base_p4d;
+	unsigned long next;
+
+	if (!pgtable_l5_enabled) {
+		p4dp = (p4d_t *)pgdp;
+	} else {
+		base_p4d = pt_ops.get_p4d_virt(pfn_to_phys(_pgd_pfn(*pgdp)));
+		p4dp = base_p4d + p4d_index(vaddr);
+	}
+
+	do {
+		next = p4d_addr_end(vaddr, end);
+
+		if (pgtable_l4_enabled && IS_ALIGNED(vaddr, P4D_SIZE) &&
+		    (next - vaddr) >= P4D_SIZE) {
+			p4d_clear(p4dp);
+			continue;
+		}
+
+		kasan_early_clear_pud(p4dp, vaddr, next);
+	} while (p4dp++, vaddr = next, vaddr != end);
+}
+
+static void __init kasan_early_clear_pgd(pgd_t *pgdp,
+					 unsigned long vaddr, unsigned long end)
+{
+	unsigned long next;
+
+	do {
+		next = pgd_addr_end(vaddr, end);
+
+		if (pgtable_l5_enabled && IS_ALIGNED(vaddr, PGDIR_SIZE) &&
+		    (next - vaddr) >= PGDIR_SIZE) {
+			pgd_clear(pgdp);
+			continue;
+		}
+
+		kasan_early_clear_p4d(pgdp, vaddr, next);
+	} while (pgdp++, vaddr = next, vaddr != end);
+}
+
+static void __init kasan_early_populate_pud(p4d_t *p4dp,
+					    unsigned long vaddr,
+					    unsigned long end)
+{
+	pud_t *pudp, *base_pud;
+	phys_addr_t phys_addr;
+	unsigned long next;
+
+	if (!pgtable_l4_enabled) {
+		pudp = (pud_t *)p4dp;
+	} else {
+		base_pud = pt_ops.get_pud_virt(pfn_to_phys(_p4d_pfn(*p4dp)));
+		pudp = base_pud + pud_index(vaddr);
+	}
+
+	do {
+		next = pud_addr_end(vaddr, end);
+
+		if (pud_none(*pudp) && IS_ALIGNED(vaddr, PUD_SIZE) &&
+		    (next - vaddr) >= PUD_SIZE) {
+			phys_addr = __pa((uintptr_t)kasan_early_shadow_pmd);
+			set_pud(pudp, pfn_pud(PFN_DOWN(phys_addr), PAGE_TABLE));
+			continue;
+		}
+
+		BUG();
+	} while (pudp++, vaddr = next, vaddr != end);
+}
+
+static void __init kasan_early_populate_p4d(pgd_t *pgdp,
+					    unsigned long vaddr,
+					    unsigned long end)
+{
+	p4d_t *p4dp, *base_p4d;
+	phys_addr_t phys_addr;
+	unsigned long next;
+
+	/*
+	 * We can't use pgd_page_vaddr here as it would return a linear
+	 * mapping address but it is not mapped yet, but when populating
+	 * early_pg_dir, we need the physical address and when populating
+	 * swapper_pg_dir, we need the kernel virtual address so use
+	 * pt_ops facility.
+	 * Note that this test is then completely equivalent to
+	 * p4dp = p4d_offset(pgdp, vaddr)
+	 */
+	if (!pgtable_l5_enabled) {
+		p4dp = (p4d_t *)pgdp;
+	} else {
+		base_p4d = pt_ops.get_p4d_virt(pfn_to_phys(_pgd_pfn(*pgdp)));
+		p4dp = base_p4d + p4d_index(vaddr);
+	}
+
+	do {
+		next = p4d_addr_end(vaddr, end);
+
+		if (p4d_none(*p4dp) && IS_ALIGNED(vaddr, P4D_SIZE) &&
+		    (next - vaddr) >= P4D_SIZE) {
+			phys_addr = __pa((uintptr_t)kasan_early_shadow_pud);
+			set_p4d(p4dp, pfn_p4d(PFN_DOWN(phys_addr), PAGE_TABLE));
+			continue;
+		}
+
+		kasan_early_populate_pud(p4dp, vaddr, next);
+	} while (p4dp++, vaddr = next, vaddr != end);
+}
+
+static void __init kasan_early_populate_pgd(pgd_t *pgdp,
+					    unsigned long vaddr,
+					    unsigned long end)
+{
+	phys_addr_t phys_addr;
+	unsigned long next;
+
+	do {
+		next = pgd_addr_end(vaddr, end);
+
+		if (pgd_none(*pgdp) && IS_ALIGNED(vaddr, PGDIR_SIZE) &&
+		    (next - vaddr) >= PGDIR_SIZE) {
+			phys_addr = __pa((uintptr_t)kasan_early_shadow_p4d);
+			set_pgd(pgdp, pfn_pgd(PFN_DOWN(phys_addr), PAGE_TABLE));
+			continue;
+		}
+
+		kasan_early_populate_p4d(pgdp, vaddr, next);
 	} while (pgdp++, vaddr = next, vaddr != end);
 }
 
@@ -295,16 +350,16 @@ asmlinkage void __init kasan_early_init(void)
 					PAGE_TABLE));
 	}
 
-	kasan_populate_pgd(early_pg_dir + pgd_index(KASAN_SHADOW_START),
-			   KASAN_SHADOW_START, KASAN_SHADOW_END, true);
+	kasan_early_populate_pgd(early_pg_dir + pgd_index(KASAN_SHADOW_START),
+				 KASAN_SHADOW_START, KASAN_SHADOW_END);
 
 	local_flush_tlb_all();
 }
 
 void __init kasan_swapper_init(void)
 {
-	kasan_populate_pgd(pgd_offset_k(KASAN_SHADOW_START),
-			   KASAN_SHADOW_START, KASAN_SHADOW_END, true);
+	kasan_early_populate_pgd(pgd_offset_k(KASAN_SHADOW_START),
+				 KASAN_SHADOW_START, KASAN_SHADOW_END);
 
 	local_flush_tlb_all();
 }
@@ -314,118 +369,65 @@ static void __init kasan_populate(void *start, void *end)
 	unsigned long vaddr = (unsigned long)start & PAGE_MASK;
 	unsigned long vend = PAGE_ALIGN((unsigned long)end);
 
-	kasan_populate_pgd(pgd_offset_k(vaddr), vaddr, vend, false);
-
-	local_flush_tlb_all();
-	memset(start, KASAN_SHADOW_INIT, end - start);
+	kasan_populate_pgd(pgd_offset_k(vaddr), vaddr, vend);
 }
 
-static void __init kasan_shallow_populate_pmd(pgd_t *pgdp,
+static void __init kasan_shallow_populate_pud(p4d_t *p4d,
 					      unsigned long vaddr, unsigned long end)
 {
 	unsigned long next;
-	pmd_t *pmdp, *base_pmd;
-	bool is_kasan_pte;
-
-	base_pmd = (pmd_t *)pgd_page_vaddr(*pgdp);
-	pmdp = base_pmd + pmd_index(vaddr);
-
-	do {
-		next = pmd_addr_end(vaddr, end);
-		is_kasan_pte = (pmd_pgtable(*pmdp) == lm_alias(kasan_early_shadow_pte));
-
-		if (is_kasan_pte)
-			pmd_clear(pmdp);
-	} while (pmdp++, vaddr = next, vaddr != end);
-}
-
-static void __init kasan_shallow_populate_pud(pgd_t *pgdp,
-					      unsigned long vaddr, unsigned long end)
-{
-	unsigned long next;
-	pud_t *pudp, *base_pud;
-	pmd_t *base_pmd;
-	bool is_kasan_pmd;
-
-	base_pud = (pud_t *)pgd_page_vaddr(*pgdp);
-	pudp = base_pud + pud_index(vaddr);
+	void *p;
+	pud_t *pud_k = pud_offset(p4d, vaddr);
 
 	do {
 		next = pud_addr_end(vaddr, end);
-		is_kasan_pmd = (pud_pgtable(*pudp) == lm_alias(kasan_early_shadow_pmd));
 
-		if (!is_kasan_pmd)
+		if (pud_none(*pud_k)) {
+			p = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
+			set_pud(pud_k, pfn_pud(PFN_DOWN(__pa(p)), PAGE_TABLE));
 			continue;
+		}
 
-		base_pmd = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
-		set_pud(pudp, pfn_pud(PFN_DOWN(__pa(base_pmd)), PAGE_TABLE));
-
-		if (IS_ALIGNED(vaddr, PUD_SIZE) && (next - vaddr) >= PUD_SIZE)
-			continue;
-
-		memcpy(base_pmd, (void *)kasan_early_shadow_pmd, PAGE_SIZE);
-		kasan_shallow_populate_pmd((pgd_t *)pudp, vaddr, next);
-	} while (pudp++, vaddr = next, vaddr != end);
+		BUG();
+	} while (pud_k++, vaddr = next, vaddr != end);
 }
 
-static void __init kasan_shallow_populate_p4d(pgd_t *pgdp,
+static void __init kasan_shallow_populate_p4d(pgd_t *pgd,
 					      unsigned long vaddr, unsigned long end)
 {
 	unsigned long next;
-	p4d_t *p4dp, *base_p4d;
-	pud_t *base_pud;
-	bool is_kasan_pud;
-
-	base_p4d = (p4d_t *)pgd_page_vaddr(*pgdp);
-	p4dp = base_p4d + p4d_index(vaddr);
+	void *p;
+	p4d_t *p4d_k = p4d_offset(pgd, vaddr);
 
 	do {
 		next = p4d_addr_end(vaddr, end);
-		is_kasan_pud = (p4d_pgtable(*p4dp) == lm_alias(kasan_early_shadow_pud));
 
-		if (!is_kasan_pud)
+		if (p4d_none(*p4d_k)) {
+			p = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
+			set_p4d(p4d_k, pfn_p4d(PFN_DOWN(__pa(p)), PAGE_TABLE));
 			continue;
+		}
 
-		base_pud = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
-		set_p4d(p4dp, pfn_p4d(PFN_DOWN(__pa(base_pud)), PAGE_TABLE));
-
-		if (IS_ALIGNED(vaddr, P4D_SIZE) && (next - vaddr) >= P4D_SIZE)
-			continue;
-
-		memcpy(base_pud, (void *)kasan_early_shadow_pud, PAGE_SIZE);
-		kasan_shallow_populate_pud((pgd_t *)p4dp, vaddr, next);
-	} while (p4dp++, vaddr = next, vaddr != end);
+		kasan_shallow_populate_pud(p4d_k, vaddr, end);
+	} while (p4d_k++, vaddr = next, vaddr != end);
 }
 
-#define kasan_shallow_populate_pgd_next(pgdp, vaddr, next)			\
-		(pgtable_l5_enabled ?						\
-		kasan_shallow_populate_p4d(pgdp, vaddr, next) :			\
-		(pgtable_l4_enabled ?						\
-		kasan_shallow_populate_pud(pgdp, vaddr, next) :			\
-		kasan_shallow_populate_pmd(pgdp, vaddr, next)))
-
 static void __init kasan_shallow_populate_pgd(unsigned long vaddr, unsigned long end)
 {
 	unsigned long next;
 	void *p;
 	pgd_t *pgd_k = pgd_offset_k(vaddr);
-	bool is_kasan_pgd_next;
 
 	do {
 		next = pgd_addr_end(vaddr, end);
-		is_kasan_pgd_next = (pgd_page_vaddr(*pgd_k) ==
-				     (unsigned long)lm_alias(kasan_early_shadow_pgd_next));
 
-		if (is_kasan_pgd_next) {
+		if (pgd_none(*pgd_k)) {
 			p = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 			set_pgd(pgd_k, pfn_pgd(PFN_DOWN(__pa(p)), PAGE_TABLE));
+			continue;
 		}
 
-		if (IS_ALIGNED(vaddr, PGDIR_SIZE) && (next - vaddr) >= PGDIR_SIZE)
-			continue;
-
-		memcpy(p, (void *)kasan_early_shadow_pgd_next, PAGE_SIZE);
-		kasan_shallow_populate_pgd_next(pgd_k, vaddr, next);
+		kasan_shallow_populate_p4d(pgd_k, vaddr, next);
 	} while (pgd_k++, vaddr = next, vaddr != end);
 }
 
@@ -435,7 +437,37 @@ static void __init kasan_shallow_populate(void *start, void *end)
 	unsigned long vend = PAGE_ALIGN((unsigned long)end);
 
 	kasan_shallow_populate_pgd(vaddr, vend);
-	local_flush_tlb_all();
+}
+
+static void create_tmp_mapping(void)
+{
+	void *ptr;
+	p4d_t *base_p4d;
+
+	/*
+	 * We need to clean the early mapping: this is hard to achieve "in-place",
+	 * so install a temporary mapping like arm64 and x86 do.
+	 */
+	memcpy(tmp_pg_dir, swapper_pg_dir, sizeof(pgd_t) * PTRS_PER_PGD);
+
+	/* Copy the last p4d since it is shared with the kernel mapping. */
+	if (pgtable_l5_enabled) {
+		ptr = (p4d_t *)pgd_page_vaddr(*pgd_offset_k(KASAN_SHADOW_END));
+		memcpy(tmp_p4d, ptr, sizeof(p4d_t) * PTRS_PER_P4D);
+		set_pgd(&tmp_pg_dir[pgd_index(KASAN_SHADOW_END)],
+			pfn_pgd(PFN_DOWN(__pa(tmp_p4d)), PAGE_TABLE));
+		base_p4d = tmp_p4d;
+	} else {
+		base_p4d = (p4d_t *)tmp_pg_dir;
+	}
+
+	/* Copy the last pud since it is shared with the kernel mapping. */
+	if (pgtable_l4_enabled) {
+		ptr = (pud_t *)p4d_page_vaddr(*(base_p4d + p4d_index(KASAN_SHADOW_END)));
+		memcpy(tmp_pud, ptr, sizeof(pud_t) * PTRS_PER_PUD);
+		set_p4d(&base_p4d[p4d_index(KASAN_SHADOW_END)],
+			pfn_p4d(PFN_DOWN(__pa(tmp_pud)), PAGE_TABLE));
+	}
 }
 
 void __init kasan_init(void)
@@ -443,10 +475,27 @@ void __init kasan_init(void)
 	phys_addr_t p_start, p_end;
 	u64 i;
 
-	if (IS_ENABLED(CONFIG_KASAN_VMALLOC))
+	create_tmp_mapping();
+	csr_write(CSR_SATP, PFN_DOWN(__pa(tmp_pg_dir)) | satp_mode);
+
+	kasan_early_clear_pgd(pgd_offset_k(KASAN_SHADOW_START),
+			      KASAN_SHADOW_START, KASAN_SHADOW_END);
+
+	kasan_populate_early_shadow((void *)kasan_mem_to_shadow((void *)FIXADDR_START),
+				    (void *)kasan_mem_to_shadow((void *)VMALLOC_START));
+
+	if (IS_ENABLED(CONFIG_KASAN_VMALLOC)) {
 		kasan_shallow_populate(
 			(void *)kasan_mem_to_shadow((void *)VMALLOC_START),
 			(void *)kasan_mem_to_shadow((void *)VMALLOC_END));
+		/* Shallow populate modules and BPF which are vmalloc-allocated */
+		kasan_shallow_populate(
+			(void *)kasan_mem_to_shadow((void *)MODULES_VADDR),
+			(void *)kasan_mem_to_shadow((void *)MODULES_END));
+	} else {
+		kasan_populate_early_shadow((void *)kasan_mem_to_shadow((void *)VMALLOC_START),
+					    (void *)kasan_mem_to_shadow((void *)VMALLOC_END));
+	}
 
 	/* Populate the linear mapping */
 	for_each_mem_range(i, &p_start, &p_end) {
@@ -459,8 +508,8 @@ void __init kasan_init(void)
 		kasan_populate(kasan_mem_to_shadow(start), kasan_mem_to_shadow(end));
 	}
 
-	/* Populate kernel, BPF, modules mapping */
-	kasan_populate(kasan_mem_to_shadow((const void *)MODULES_VADDR),
+	/* Populate kernel */
+	kasan_populate(kasan_mem_to_shadow((const void *)MODULES_END),
 		       kasan_mem_to_shadow((const void *)MODULES_VADDR + SZ_2G));
 
 	for (i = 0; i < PTRS_PER_PTE; i++)
@@ -471,4 +520,7 @@ void __init kasan_init(void)
 
 	memset(kasan_early_shadow_page, KASAN_SHADOW_INIT, PAGE_SIZE);
 	init_task.kasan_depth = 0;
+
+	csr_write(CSR_SATP, PFN_DOWN(__pa(swapper_pg_dir)) | satp_mode);
+	local_flush_tlb_all();
 }

arch/riscv/mm/physaddr.c

@@ -33,3 +33,19 @@ phys_addr_t __phys_addr_symbol(unsigned long x)
 	return __va_to_pa_nodebug(x);
 }
 EXPORT_SYMBOL(__phys_addr_symbol);
+
+phys_addr_t linear_mapping_va_to_pa(unsigned long x)
+{
+	BUG_ON(!kernel_map.va_pa_offset);
+
+	return ((unsigned long)(x) - kernel_map.va_pa_offset);
+}
+EXPORT_SYMBOL(linear_mapping_va_to_pa);
+
+void *linear_mapping_pa_to_va(unsigned long x)
+{
+	BUG_ON(!kernel_map.va_pa_offset);
+
+	return ((void *)((unsigned long)(x) + kernel_map.va_pa_offset));
+}
+EXPORT_SYMBOL(linear_mapping_pa_to_va);

arch/riscv/mm/ptdump.c

@@ -59,10 +59,6 @@ struct ptd_mm_info {
 };
 
 enum address_markers_idx {
-#ifdef CONFIG_KASAN
-	KASAN_SHADOW_START_NR,
-	KASAN_SHADOW_END_NR,
-#endif
 	FIXMAP_START_NR,
 	FIXMAP_END_NR,
 	PCI_IO_START_NR,
@@ -74,6 +70,10 @@ enum address_markers_idx {
 	VMALLOC_START_NR,
 	VMALLOC_END_NR,
 	PAGE_OFFSET_NR,
+#ifdef CONFIG_KASAN
+	KASAN_SHADOW_START_NR,
+	KASAN_SHADOW_END_NR,
+#endif
 #ifdef CONFIG_64BIT
 	MODULES_MAPPING_NR,
 	KERNEL_MAPPING_NR,
@@ -82,10 +82,6 @@ enum address_markers_idx {
 };
 
 static struct addr_marker address_markers[] = {
-#ifdef CONFIG_KASAN
-	{0, "Kasan shadow start"},
-	{0, "Kasan shadow end"},
-#endif
 	{0, "Fixmap start"},
 	{0, "Fixmap end"},
 	{0, "PCI I/O start"},
@@ -97,6 +93,10 @@ static struct addr_marker address_markers[] = {
 	{0, "vmalloc() area"},
 	{0, "vmalloc() end"},
 	{0, "Linear mapping"},
+#ifdef CONFIG_KASAN
+	{0, "Kasan shadow start"},
+	{0, "Kasan shadow end"},
+#endif
 #ifdef CONFIG_64BIT
 	{0, "Modules/BPF mapping"},
 	{0, "Kernel mapping"},
@@ -362,10 +362,6 @@ static int __init ptdump_init(void)
 {
 	unsigned int i, j;
 
-#ifdef CONFIG_KASAN
-	address_markers[KASAN_SHADOW_START_NR].start_address = KASAN_SHADOW_START;
-	address_markers[KASAN_SHADOW_END_NR].start_address = KASAN_SHADOW_END;
-#endif
 	address_markers[FIXMAP_START_NR].start_address = FIXADDR_START;
 	address_markers[FIXMAP_END_NR].start_address = FIXADDR_TOP;
 	address_markers[PCI_IO_START_NR].start_address = PCI_IO_START;
@@ -377,6 +373,10 @@ static int __init ptdump_init(void)
 	address_markers[VMALLOC_START_NR].start_address = VMALLOC_START;
 	address_markers[VMALLOC_END_NR].start_address = VMALLOC_END;
 	address_markers[PAGE_OFFSET_NR].start_address = PAGE_OFFSET;
+#ifdef CONFIG_KASAN
+	address_markers[KASAN_SHADOW_START_NR].start_address = KASAN_SHADOW_START;
+	address_markers[KASAN_SHADOW_END_NR].start_address = KASAN_SHADOW_END;
+#endif
 #ifdef CONFIG_64BIT
 	address_markers[MODULES_MAPPING_NR].start_address = MODULES_VADDR;
 	address_markers[KERNEL_MAPPING_NR].start_address = kernel_map.virt_addr;

arch/riscv/tools/relocs_check.sh

@@ -0,0 +1,26 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Based on powerpc relocs_check.sh
+
+# This script checks the relocations of a vmlinux for "suspicious"
+# relocations.
+
+if [ $# -lt 3 ]; then
+        echo "$0 [path to objdump] [path to nm] [path to vmlinux]" 1>&2
+        exit 1
+fi
+
+bad_relocs=$(
+${srctree}/scripts/relocs_check.sh "$@" |
+	# These relocations are okay
+	#	R_RISCV_RELATIVE
+	grep -F -w -v 'R_RISCV_RELATIVE'
+)
+
+if [ -z "$bad_relocs" ]; then
+	exit 0
+fi
+
+num_bad=$(echo "$bad_relocs" | wc -l)
+echo "WARNING: $num_bad bad relocations"
+echo "$bad_relocs"

drivers/of/fdt.c

@@ -887,12 +887,13 @@ const void * __init of_flat_dt_match_machine(const void *default_match,
 static void __early_init_dt_declare_initrd(unsigned long start,
 					   unsigned long end)
 {
-	/* ARM64 would cause a BUG to occur here when CONFIG_DEBUG_VM is
-	 * enabled since __va() is called too early. ARM64 does make use
-	 * of phys_initrd_start/phys_initrd_size so we can skip this
-	 * conversion.
+	/*
+	 * __va() is not yet available this early on some platforms. In that
+	 * case, the platform uses phys_initrd_start/phys_initrd_size instead
+	 * and does the VA conversion itself.
 	 */
-	if (!IS_ENABLED(CONFIG_ARM64)) {
+	if (!IS_ENABLED(CONFIG_ARM64) &&
+	    !(IS_ENABLED(CONFIG_RISCV) && IS_ENABLED(CONFIG_64BIT))) {
 		initrd_start = (unsigned long)__va(start);
 		initrd_end = (unsigned long)__va(end);
 		initrd_below_start_ok = 1;

scripts/relocs_check.sh

@@ -0,0 +1,20 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+# Get a list of all the relocations, remove from it the relocations
+# that are known to be legitimate and return this list to arch specific
+# script that will look for suspicious relocations.
+
+objdump="$1"
+nm="$2"
+vmlinux="$3"
+
+# Remove from the possible bad relocations those that match an undefined
+# weak symbol which will result in an absolute relocation to 0.
+# Weak unresolved symbols are of that form in nm output:
+# "                  w _binary__btf_vmlinux_bin_end"
+undef_weak_symbols=$($nm "$vmlinux" | awk '$1 ~ /w/ { print $2 }')
+
+$objdump -R "$vmlinux" |
+	grep -E '\<R_' |
+	([ "$undef_weak_symbols" ] && grep -F -w -v "$undef_weak_symbols" || cat)

tools/testing/selftests/Makefile

@@ -64,6 +64,7 @@ TARGETS += pstore
 TARGETS += ptrace
 TARGETS += openat2
 TARGETS += resctrl
+TARGETS += riscv
 TARGETS += rlimits
 TARGETS += rseq
 TARGETS += rtc

tools/testing/selftests/riscv/Makefile

@@ -0,0 +1,58 @@
+# SPDX-License-Identifier: GPL-2.0
+# Originally tools/testing/arm64/Makefile
+
+# When ARCH not overridden for crosscompiling, lookup machine
+ARCH ?= $(shell uname -m 2>/dev/null || echo not)
+
+ifneq (,$(filter $(ARCH),riscv))
+RISCV_SUBTARGETS ?= hwprobe
+else
+RISCV_SUBTARGETS :=
+endif
+
+CFLAGS := -Wall -O2 -g
+
+# A proper top_srcdir is needed by KSFT(lib.mk)
+top_srcdir = $(realpath ../../../../)
+
+# Additional include paths needed by kselftest.h and local headers
+CFLAGS += -I$(top_srcdir)/tools/testing/selftests/
+
+CFLAGS += $(KHDR_INCLUDES)
+
+export CFLAGS
+export top_srcdir
+
+all:
+	@for DIR in $(RISCV_SUBTARGETS); do				\
+		BUILD_TARGET=$(OUTPUT)/$$DIR;			\
+		mkdir -p $$BUILD_TARGET;			\
+		$(MAKE) OUTPUT=$$BUILD_TARGET -C $$DIR $@;		\
+	done
+
+install: all
+	@for DIR in $(RISCV_SUBTARGETS); do				\
+		BUILD_TARGET=$(OUTPUT)/$$DIR;			\
+		$(MAKE) OUTPUT=$$BUILD_TARGET -C $$DIR $@;		\
+	done
+
+run_tests: all
+	@for DIR in $(RISCV_SUBTARGETS); do				\
+		BUILD_TARGET=$(OUTPUT)/$$DIR;			\
+		$(MAKE) OUTPUT=$$BUILD_TARGET -C $$DIR $@;		\
+	done
+
+# Avoid any output on non riscv on emit_tests
+emit_tests: all
+	@for DIR in $(RISCV_SUBTARGETS); do				\
+		BUILD_TARGET=$(OUTPUT)/$$DIR;			\
+		$(MAKE) OUTPUT=$$BUILD_TARGET -C $$DIR $@;		\
+	done
+
+clean:
+	@for DIR in $(RISCV_SUBTARGETS); do				\
+		BUILD_TARGET=$(OUTPUT)/$$DIR;			\
+		$(MAKE) OUTPUT=$$BUILD_TARGET -C $$DIR $@;		\
+	done
+
+.PHONY: all clean install run_tests emit_tests

tools/testing/selftests/riscv/hwprobe/Makefile

@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2021 ARM Limited
+# Originally tools/testing/arm64/abi/Makefile
+
+TEST_GEN_PROGS := hwprobe
+
+include ../../lib.mk
+
+$(OUTPUT)/hwprobe: hwprobe.c sys_hwprobe.S
+	$(CC) -o$@ $(CFLAGS) $(LDFLAGS) $^

tools/testing/selftests/riscv/hwprobe/hwprobe.c

@@ -0,0 +1,90 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <stddef.h>
+#include <asm/hwprobe.h>
+
+/*
+ * Rather than relying on having a new enough libc to define this, just do it
+ * ourselves.  This way we don't need to be coupled to a new-enough libc to
+ * contain the call.
+ */
+long riscv_hwprobe(struct riscv_hwprobe *pairs, size_t pair_count,
+		   size_t cpu_count, unsigned long *cpus, unsigned int flags);
+
+int main(int argc, char **argv)
+{
+	struct riscv_hwprobe pairs[8];
+	unsigned long cpus;
+	long out;
+
+	/* Fake the CPU_SET ops. */
+	cpus = -1;
+
+	/*
+	 * Just run a basic test: pass enough pairs to get up to the base
+	 * behavior, and then check to make sure it's sane.
+	 */
+	for (long i = 0; i < 8; i++)
+		pairs[i].key = i;
+	out = riscv_hwprobe(pairs, 8, 1, &cpus, 0);
+	if (out != 0)
+		return -1;
+	for (long i = 0; i < 4; ++i) {
+		/* Fail if the kernel claims not to recognize a base key. */
+		if ((i < 4) && (pairs[i].key != i))
+			return -2;
+
+		if (pairs[i].key != RISCV_HWPROBE_KEY_BASE_BEHAVIOR)
+			continue;
+
+		if (pairs[i].value & RISCV_HWPROBE_BASE_BEHAVIOR_IMA)
+			continue;
+
+		return -3;
+	}
+
+	/*
+	 * This should also work with a NULL CPU set, but should not work
+	 * with an improperly supplied CPU set.
+	 */
+	out = riscv_hwprobe(pairs, 8, 0, 0, 0);
+	if (out != 0)
+		return -4;
+
+	out = riscv_hwprobe(pairs, 8, 0, &cpus, 0);
+	if (out == 0)
+		return -5;
+
+	out = riscv_hwprobe(pairs, 8, 1, 0, 0);
+	if (out == 0)
+		return -6;
+
+	/*
+	 * Check that keys work by providing one that we know exists, and
+	 * checking to make sure the resultig pair is what we asked for.
+	 */
+	pairs[0].key = RISCV_HWPROBE_KEY_BASE_BEHAVIOR;
+	out = riscv_hwprobe(pairs, 1, 1, &cpus, 0);
+	if (out != 0)
+		return -7;
+	if (pairs[0].key != RISCV_HWPROBE_KEY_BASE_BEHAVIOR)
+		return -8;
+
+	/*
+	 * Check that an unknown key gets overwritten with -1,
+	 * but doesn't block elements after it.
+	 */
+	pairs[0].key = 0x5555;
+	pairs[1].key = 1;
+	pairs[1].value = 0xAAAA;
+	out = riscv_hwprobe(pairs, 2, 0, 0, 0);
+	if (out != 0)
+		return -9;
+
+	if (pairs[0].key != -1)
+		return -10;
+
+	if ((pairs[1].key != 1) || (pairs[1].value == 0xAAAA))
+		return -11;
+
+	return 0;
+}

tools/testing/selftests/riscv/hwprobe/sys_hwprobe.S

@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2023 Rivos, Inc */
+
+.text
+.global riscv_hwprobe
+riscv_hwprobe:
+	# Put __NR_riscv_hwprobe in the syscall number register, then just shim
+	# back the kernel's return.  This doesn't do any sort of errno
+	# handling, the caller can deal with it.
+	li a7, 258
+	ecall
+	ret