Commit Graph

17 Commits

Author SHA1 Message Date
Christoph Hellwig
e8d444d3e9
riscv: remove address space overrides using set_fs()
Stop providing the possibility to override the address space using
set_fs() now that there is no need for that any more.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-10-04 10:27:10 -07:00
Linus Torvalds
dbf8381731 RISC-V Patches for the 5.9 Merge Window, Part 1
We have a lot of new kernel features for this merge window:
 
 * ARCH_SUPPORTS_ATOMIC_RMW, to allow OSQ locks to be enabled.
 * The ability to enable NO_HZ_FULL
 * Support for enabling kcov, kmemleak, stack protector, and VM debugging.
 * JUMP_LABEL support.
 
 There are also a handful of cleanups.
 
 next points out a trivial Kconfig merge conflict.  I don't see any way to have
 done this better: the symbols are sorted, it just happens that
 HAVE_COPY_THREAD_TLS was in the middle of two new symbols.  In case it helps
 any, here's a pretty current conflict resolution:
 
 diff --cc arch/riscv/Kconfig
 index bc37241a6875,6c4bce7cad8a..7b5905529146
 --- a/arch/riscv/Kconfig
 +++ b/arch/riscv/Kconfig
 @@@ -57,9 -54,6 +59,8 @@@ config RISC
         select HAVE_ARCH_SECCOMP_FILTER
         select HAVE_ARCH_TRACEHOOK
         select HAVE_ASM_MODVERSIONS
  +      select HAVE_CONTEXT_TRACKING
 -       select HAVE_COPY_THREAD_TLS
  +      select HAVE_DEBUG_KMEMLEAK
         select HAVE_DMA_CONTIGUOUS if MMU
         select HAVE_EBPF_JIT if MMU
         select HAVE_FUTEX_CMPXCHG if FUTEX
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Merge tag 'riscv-for-linus-5.9-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:
 "We have a lot of new kernel features for this merge window:

   - ARCH_SUPPORTS_ATOMIC_RMW, to allow OSQ locks to be enabled

   - The ability to enable NO_HZ_FULL

   - Support for enabling kcov, kmemleak, stack protector, and VM
     debugging

   - JUMP_LABEL support

  There are also a handful of cleanups"

* tag 'riscv-for-linus-5.9-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (24 commits)
  riscv: disable stack-protector for vDSO
  RISC-V: Fix build warning for smpboot.c
  riscv: fix build warning of mm/pageattr
  riscv: Fix build warning for mm/init
  RISC-V: Setup exception vector early
  riscv: Select ARCH_HAS_DEBUG_VM_PGTABLE
  riscv: Use generic pgprot_* macros from <linux/pgtable.h>
  mm: pgtable: Make generic pgprot_* macros available for no-MMU
  riscv: Cleanup unnecessary define in asm-offset.c
  riscv: Add jump-label implementation
  riscv: Support R_RISCV_ADD64 and R_RISCV_SUB64 relocs
  Replace HTTP links with HTTPS ones: RISC-V
  riscv: Add STACKPROTECTOR supported
  riscv: Fix typo in asm/hwcap.h uapi header
  riscv: Add kmemleak support
  riscv: Allow building with kcov coverage
  riscv: Enable context tracking
  riscv: Support irq_work via self IPIs
  riscv: Enable LOCKDEP_SUPPORT & fixup TRACE_IRQFLAGS_SUPPORT
  riscv: Fixup lockdep_assert_held with wrong param cpu_running
  ...
2020-08-07 10:11:12 -07:00
Guo Ren
f2c9699f65
riscv: Add STACKPROTECTOR supported
The -fstack-protector & -fstack-protector-strong features are from
gcc. The patch only add basic kernel support to stack-protector
feature and some arch could have its own solution such as
ARM64_PTR_AUTH.

After enabling STACKPROTECTOR and STACKPROTECTOR_STRONG, the .text
size is expanded from  0x7de066 to 0x81fb32 (only 5%) to add canary
checking code.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30 11:37:39 -07:00
Christian Brauner
714acdbd1c
arch: rename copy_thread_tls() back to copy_thread()
Now that HAVE_COPY_THREAD_TLS has been removed, rename copy_thread_tls()
back simply copy_thread(). It's a simpler name, and doesn't imply that only
tls is copied here. This finishes an outstanding chunk of internal process
creation work since we've added clone3().

Cc: linux-arch@vger.kernel.org
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>A
Acked-by: Stafford Horne <shorne@gmail.com>
Acked-by: Greentime Hu <green.hu@gmail.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>A
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-07-04 23:41:37 +02:00
Palmer Dabbelt
8356c379cf
RISC-V: gp_in_global needs register keyword
The Intel kernel build robot recently pointed out that I missed the
register keyword on this one when I refactored the code to remove local
register variables (which aren't supported by LLVM).  GCC's manual
indicates that global register variables must have the register keyword,
As far as I can tell lacking the register keyword causes GCC to ignore
the __asm__ and treat this as a regular variable, but I'm not sure how
that didn't show up as some sort of failure.

Fixes: 52e7c52d2d ("RISC-V: Stop relying on GCC's register allocator's hueristics")
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-21 13:28:26 -07:00
Palmer Dabbelt
52e7c52d2d
RISC-V: Stop relying on GCC's register allocator's hueristics
GCC allows users to hint to the register allocation that a variable should be
placed in a register by using a syntax along the lines of

    function(...) {
        register long in_REG __asm__("REG");
    }

We've abused this a bit throughout the RISC-V port to access fixed registers
directly as C variables.  In practice it's never going to blow up because GCC
isn't going to allocate these registers, but it's not a well defined syntax so
we really shouldn't be relying upon this.  Luckily there is a very similar but
well defined syntax that allows us to still access these registers directly as
C variables, which is to simply declare the register variables globally.  For
fixed variables this doesn't change the ABI.

LLVM disallows this ambiguous syntax, so this isn't just strictly a formatting
change.

Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-03 10:28:13 -08:00
Amanieu d'Antras
20bda4ed62
riscv: Implement copy_thread_tls
This is required for clone3 which passes the TLS value through a
struct rather than a register.

Signed-off-by: Amanieu d'Antras <amanieu@gmail.com>
Cc: linux-riscv@lists.infradead.org
Cc: <stable@vger.kernel.org> # 5.3.x
Link: https://lore.kernel.org/r/20200102172413.654385-6-amanieu@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-01-07 13:31:23 +01:00
Christoph Hellwig
a4c3733d32 riscv: abstract out CSR names for supervisor vs machine mode
Many of the privileged CSRs exist in a supervisor and machine version
that are used very similarly.  Provide versions of the CSR names and
fields that map to either the S-mode or M-mode variant depending on
a new CONFIG_RISCV_M_MODE kconfig symbol.

Contains contributions from Damien Le Moal <Damien.LeMoal@wdc.com>
and Paul Walmsley <paul.walmsley@sifive.com>.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de> # for drivers/clocksource, drivers/irqchip
[paul.walmsley@sifive.com: updated to apply]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-11-05 09:20:42 -08:00
Paul Walmsley
5ed881bc3a riscv: add missing header file includes
sparse identifies several missing prototypes caused by missing
preprocessor include directives:

arch/riscv/kernel/cpufeature.c:16:6: warning: symbol 'has_fpu' was not declared. Should it be static?
arch/riscv/kernel/process.c:26:6: warning: symbol 'arch_cpu_idle' was not declared. Should it be static?
arch/riscv/kernel/reset.c:15:6: warning: symbol 'pm_power_off' was not declared. Should it be static?
arch/riscv/kernel/syscall_table.c:15:6: warning: symbol 'sys_call_table' was not declared. Should it be static?
arch/riscv/kernel/traps.c:149:13: warning: symbol 'trap_init' was not declared. Should it be static?
arch/riscv/kernel/vdso.c:54:5: warning: symbol 'arch_setup_additional_pages' was not declared. Should it be static?
arch/riscv/kernel/smp.c:64:6: warning: symbol 'arch_match_cpu_phys_id' was not declared. Should it be static?
arch/riscv/kernel/module-sections.c:89:5: warning: symbol 'module_frob_arch_sections' was not declared. Should it be static?
arch/riscv/mm/context.c:42:6: warning: symbol 'switch_mm' was not declared. Should it be static?

Fix by including the appropriate header files in the appropriate
source files.

This patch should have no functional impact.

Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-10-28 00:46:01 -07:00
Vincent Chen
8ac71d7e46 riscv: Correct the initialized flow of FP register
The following two reasons cause FP registers are sometimes not
initialized before starting the user program.
1. Currently, the FP context is initialized in flush_thread() function
   and we expect these initial values to be restored to FP register when
   doing FP context switch. However, the FP context switch only occurs in
   switch_to function. Hence, if this process does not be scheduled out
   and scheduled in before entering the user space, the FP registers
   have no chance to initialize.
2. In flush_thread(), the state of reg->sstatus.FS inherits from the
   parent. Hence, the state of reg->sstatus.FS may be dirty. If this
   process is scheduled out during flush_thread() and initializing the
   FP register, the fstate_save() in switch_to will corrupt the FP context
   which has been initialized until flush_thread().

  To solve the 1st case, the initialization of the FP register will be
completed in start_thread(). It makes sure all FP registers are initialized
before starting the user program. For the 2nd case, the state of
reg->sstatus.FS in start_thread will be set to SR_FS_OFF to prevent this
process from corrupting FP context in doing context save. The FP state is
set to SR_FS_INITIAL in start_trhead().

Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Fixes: 7db91e57a0 ("RISC-V: Task implementation")
Cc: stable@vger.kernel.org
[paul.walmsley@sifive.com: fixed brace alignment issue reported by
 checkpatch]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-08-14 13:11:11 -07:00
Thomas Gleixner
588cb88ced treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 120
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not see the file copying or write to the free
  software foundation inc

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 12 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190523091651.231300438@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:39:02 +02:00
Alan Kao
9411ec60c2
Auto-detect whether a FPU exists
We expect that a kernel with CONFIG_FPU=y can still support no-FPU
machines. To do so, the kernel should first examine the existence of a
FPU, then do nothing if a FPU does exist; otherwise, it should
disable/bypass all FPU-related functions.

In this patch, a new global variable, has_fpu, is created and determined
when parsing the hardware capability from device tree during booting.
This variable is used in those FPU-related functions.

Signed-off-by: Alan Kao <alankao@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Cc: Vincent Chen <vincentc@andestech.com>
Cc: Zong Li <zong@andestech.com>
Cc: Nick Hu <nickhu@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22 17:02:23 -07:00
Alan Kao
9671f70614
Allow to disable FPU support
FPU codes have been separated from common part in previous patches.
This patch add the CONFIG_FPU option and some stubs, so that a no-FPU
configuration is allowed.

Signed-off-by: Alan Kao <alankao@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Cc: Vincent Chen <vincentc@andestech.com>
Cc: Zong Li <zong@andestech.com>
Cc: Nick Hu <nickhu@andestech.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22 17:02:23 -07:00
Linus Torvalds
40b9672a2f Merge branch 'work.whack-a-mole' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull asm/uaccess.h whack-a-mole from Al Viro:
 "It's linux/uaccess.h, damnit... Oh, well - eventually they'll stop
  cropping up..."

* 'work.whack-a-mole' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  asm-prototypes.h: use linux/uaccess.h, not asm/uaccess.h
  riscv: use linux/uaccess.h, not asm/uaccess.h...
  ppc: for put_user() pull linux/uaccess.h, not asm/uaccess.h
2018-01-31 19:18:12 -08:00
Christoph Hellwig
1125203c13
riscv: rename SR_* constants to match the spec
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-01-07 15:14:39 -08:00
Al Viro
5e454b5457 riscv: use linux/uaccess.h, not asm/uaccess.h...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-12-04 18:01:01 -05:00
Palmer Dabbelt
7db91e57a0 RISC-V: Task implementation
This patch contains the implementation of tasks on RISC-V, most of which
is involved in task switching.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2017-09-26 15:26:46 -07:00