linux/arch/arm64/kernel
Jun Yao 2b5548b681 arm64/mm: Separate boot-time page tables from swapper_pg_dir
Since the address of swapper_pg_dir is fixed for a given kernel image,
it is an attractive target for manipulation via an arbitrary write. To
mitigate this we'd like to make it read-only by moving it into the
rodata section.

We require that swapper_pg_dir is at a fixed offset from tramp_pg_dir
and reserved_ttbr0, so these will also need to move into rodata.
However, swapper_pg_dir is allocated along with some transient page
tables used for boot which we do not want to move into rodata.

As a step towards this, this patch separates the boot-time page tables
into a new init_pg_dir, and reduces swapper_pg_dir to the single page it
needs to be. This allows us to retain the relationship between
swapper_pg_dir, tramp_pg_dir, and swapper_pg_dir, while cleanly
separating these from the boot-time page tables.

The init_pg_dir holds all of the pgd/pud/pmd/pte levels needed during
boot, and all of these levels will be freed when we switch to the
swapper_pg_dir, which is initialized by the existing code in
paging_init(). Since we start off on the init_pg_dir, we no longer need
to allocate a transient page table in paging_init() in order to ensure
that swapper_pg_dir isn't live while we initialize it.

There should be no functional change as a result of this patch.

Signed-off-by: Jun Yao <yaojun8558363@gmail.com>
Reviewed-by: James Morse <james.morse@arm.com>
[Mark: place init_pg_dir after BSS, fold mm changes, commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-25 15:10:54 +01:00
..
probes kprobes/arm64: Fix %p uses in error messages 2018-06-21 17:33:42 +02:00
vdso arm64: Add build salt to the vDSO 2018-07-18 01:18:05 +09:00
.gitignore
acpi_numa.c arm64: numa: rework ACPI NUMA initialization 2018-07-09 18:21:40 +01:00
acpi_parking_protocol.c arm64: fix endianness annotation in acpi_parking_protocol.c 2017-06-29 11:33:15 +01:00
acpi.c arm64: acpi: fix alignment fault in accessing ACPI 2018-07-23 15:34:12 +01:00
alternative.c arm64: alternative: Use true and false for boolean values 2018-08-08 11:20:54 +01:00
arm64ksyms.c arm64: export tishift functions to modules 2018-05-21 19:00:48 +01:00
armv8_deprecated.c arm64: kill config_sctlr_el1() 2018-07-12 14:40:38 +01:00
asm-offsets.c arm64: KVM: Handle guest's ARCH_WORKAROUND_2 requests 2018-05-31 18:00:57 +01:00
cacheinfo.c arm64: Add support for ACPI based firmware tables 2018-05-17 17:28:09 +01:00
cpu_errata.c arm64: cpu_errata: Remove ARM64_MISMATCHED_CACHE_LINE_SIZE 2018-09-19 18:21:49 +01:00
cpu_ops.c arm64: cpu_ops: Add missing 'const' qualifiers 2017-12-01 13:05:08 +00:00
cpu-reset.h arm64: kexec: always reset to EL2 if present 2018-07-04 18:34:24 +01:00
cpu-reset.S arm64: idmap: Use "awx" flags for .idmap.text .pushsection directives 2018-02-06 22:53:27 +00:00
cpufeature.c arm64/cpufeatures: Factorize emulate_mrs() 2018-09-21 11:05:58 +01:00
cpuidle.c ARM64 / cpuidle: Use new cpuidle macro for entering retention state 2018-01-02 13:50:34 +00:00
cpuinfo.c arm64: cpufeature: Detect SSBS and advertise to userspace 2018-09-14 17:46:01 +01:00
crash_dump.c arm64: kdump: provide /proc/vmcore file 2017-04-05 18:31:38 +01:00
debug-monitors.c arm64: Use arm64_force_sig_info instead of force_sig_info 2018-03-06 18:52:32 +00:00
efi-entry.S arm64: Add software workaround for Falkor erratum 1041 2018-02-06 22:53:13 +00:00
efi-header.S arm64: efi: split Image code and data into separate PE/COFF sections 2017-04-04 17:50:59 +01:00
efi-rt-wrapper.S efi/arm64: Check whether x18 is preserved by runtime services calls 2018-03-09 08:58:22 +01:00
efi.c efi/arm64: Check whether x18 is preserved by runtime services calls 2018-03-09 08:58:22 +01:00
entry-fpsimd.S arm64/sve: Write ZCR_EL1 on context switch only if changed 2018-05-17 18:19:53 +01:00
entry-ftrace.S arm64: Fix static use of function graph 2017-11-03 12:05:23 +00:00
entry.S arm64: entry: Allow handling of undefined instructions from EL1 2018-09-14 17:46:17 +01:00
fpsimd.c arm64: move sve_user_{enable,disable} to <asm/fpsimd.h> 2018-07-12 14:40:39 +01:00
ftrace.c arm64: ftrace: emit ftrace-mod.o contents through code 2017-12-01 13:04:59 +00:00
head.S arm64/mm: Separate boot-time page tables from swapper_pg_dir 2018-09-25 15:10:54 +01:00
hibernate-asm.S arm64: assembler: Change order of macro arguments in phys_to_ttbr 2018-02-06 22:53:21 +00:00
hibernate.c arm64: ssbd: Restore mitigation status on CPU resume 2018-05-31 17:35:19 +01:00
hw_breakpoint.c perf/arch/arm64: Implement hw_breakpoint_arch_parse() 2018-06-26 09:07:56 +02:00
hyp-stub.S arm64: hyp-stub: Zero x0 on successful stub handling 2017-04-09 07:49:35 -07:00
image.h arm64/efi: Make strrchr() available to the EFI namespace 2018-03-05 13:45:38 -06:00
insn.c arm64: insn: Don't fallback on nosync path for general insn patching 2018-07-05 17:24:48 +01:00
io.c arm64: Avoid aligning normal memory pointers in __memcpy_{to,from}io 2017-10-24 16:23:07 +01:00
irq.c arm64: Use the new GENERIC_IRQ_MULTI_HANDLER 2018-08-03 12:14:09 +02:00
jump_label.c arm64: Avoid calling stop_machine() when patching jump labels 2018-08-17 10:26:44 +01:00
kaslr.c arm64/kernel: kaslr: reduce module randomization range to 4 GB 2018-03-08 13:49:26 +00:00
kgdb.c arm64/debug: Fix registers on sleeping tasks 2018-03-06 18:52:34 +00:00
kuser32.S
machine_kexec.c arm64: kexec: Add comment to explain use of __flush_icache_range() 2018-07-31 12:10:38 +01:00
Makefile arm64: convert compat wrappers to C 2018-07-12 14:49:48 +01:00
module-plts.c arm64/kernel: rename module_emit_adrp_veneer->module_emit_veneer_for_adrp 2018-04-24 19:07:35 +01:00
module.c arm64: Avoid flush_icache_range() in alternatives patching code 2018-06-27 18:21:53 +01:00
module.lds arm64: ftrace: emit ftrace-mod.o contents through code 2017-12-01 13:04:59 +00:00
paravirt.c arm64: introduce CONFIG_PARAVIRT, PARAVIRT_TIME_ACCOUNTING and pv_time_ops 2015-12-21 14:40:54 +00:00
pci.c PCI: Add a generic weak pcibios_align_resource() 2017-08-02 14:53:16 -05:00
perf_callchain.c arm64: unwind: remove sp from struct stackframe 2017-08-09 14:10:29 +01:00
perf_event.c arm64: perf: Add cap_user_time aarch64 2018-07-31 10:14:00 +01:00
perf_regs.c compat: Move compat_timespec/ timeval to compat_time.h 2018-04-19 13:29:54 +02:00
process.c arm64: ssbd: Add support for PSTATE.SSBS rather than trapping to EL3 2018-09-14 17:46:19 +01:00
psci.c arm64: Use __pa_symbol for kernel symbols 2017-01-12 15:05:39 +00:00
ptrace.c arm64: Add stack information to on_accessible_stack 2018-07-26 11:36:07 +01:00
reloc_test_core.c arm64: fix undefined reference to 'printk' 2018-03-19 18:14:25 +00:00
reloc_test_syms.S arm64: fix undefined reference to 'printk' 2018-03-19 18:14:25 +00:00
relocate_kernel.S arm64: Add software workaround for Falkor erratum 1041 2018-02-06 22:53:13 +00:00
return_address.c arm64: unwind: remove sp from struct stackframe 2017-08-09 14:10:29 +01:00
sdei.c arm64: sdei: Mark sdei stack helper functions as static 2018-07-31 12:08:22 +01:00
setup.c arm64: Remove unused VGA console support 2018-09-21 12:12:24 +01:00
signal32.c arm64: use {COMPAT,}SYSCALL_DEFINE0 for sigreturn 2018-07-12 14:49:48 +01:00
signal.c arm64: use {COMPAT,}SYSCALL_DEFINE0 for sigreturn 2018-07-12 14:49:48 +01:00
sleep.S arm64/mm: Pass ttbr1 as a parameter to __enable_mmu() 2018-09-25 15:10:54 +01:00
smccc-call.S firmware: qcom: scm: Fix interrupted SCM calls 2017-02-03 18:46:33 +00:00
smp_spin_table.c arm64: Use __pa_symbol for kernel symbols 2017-01-12 15:05:39 +00:00
smp.c arm64: numa: rework ACPI NUMA initialization 2018-07-09 18:21:40 +01:00
ssbd.c arm64: ssbd: Add support for PSTATE.SSBS rather than trapping to EL3 2018-09-14 17:46:19 +01:00
stacktrace.c arm64: Add stack information to on_accessible_stack 2018-07-26 11:36:07 +01:00
suspend.c arm64: mm: Support Common Not Private translations 2018-09-18 12:02:27 +01:00
sys32.c arm64: implement syscall wrappers 2018-07-12 14:49:48 +01:00
sys_compat.c signal: Ensure every siginfo we send has all bits initialized 2018-04-25 10:40:51 -05:00
sys.c arm64: implement syscall wrappers 2018-07-12 14:49:48 +01:00
syscall.c arm64: svc: Ensure hardirq tracing is updated before return 2018-07-30 17:43:39 +01:00
time.c arm64: fix unwind_frame() for filtered out fn for function graph tracing 2018-02-23 13:46:38 +00:00
topology.c arm64: topology: re-introduce numa mask check for scheduler MC selection 2018-07-06 13:18:18 +01:00
trace-events-emulation.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
traps.c arm64/cpufeatures: Emulate MRS instructions by parsing ESR_ELx.ISS 2018-09-21 11:06:18 +01:00
vdso.c arm64/vdso: Support mremap() for vDSO 2017-08-09 12:16:28 +01:00
vmlinux.lds.S arm64/mm: Separate boot-time page tables from swapper_pg_dir 2018-09-25 15:10:54 +01:00