Follow the ARM64 GCS (Guarded Control Stack) implementation approach
by reducing the shadow stack size allocation from min(RLIMIT_STACK, 4GB)
to min(RLIMIT_STACK/2, 2GB). See commit 506496bcbb ("arm64/gcs: Ensure
that new threads have a GCS")
Rationale:
1. Shadow stacks only store return addresses (8 bytes per entry), not
local variables, function parameters, or saved registers. A 2GB
shadow stack is far more than sufficient for any practical
application, even with extremely deep recursion. Using half the size
maintains adequate margin while being more resource-efficient.
2. On memory-constrained systems (e.g., platforms with only 4GB of
physical memory, which is a common configuration), allocating 4GB
of virtual address space for shadow stack per process/thread can
lead to virtual memory allocation failures when the overcommit mode
is set to OVERCOMMIT_GUESS or OVERCOMMIT_NEVER:
Error: "__vm_enough_memory: not enough memory for the allocation"
This reduces virtual address space consumption by 50% while maintaining
more than adequate space for return address storage.
Signed-off-by: Zong Li <zong.li@sifive.com>
Link: https://patch.msgid.link/20260428024105.645162-1-zong.li@sifive.com
[pjw@kernel.org: clean up patch description]
Signed-off-by: Paul Walmsley <pjw@kernel.org>
We have pre-defined ISA extension macros, here use those macros to
replace a magic number for isa2hwcap definition and some array
indexing for isa2hwcap access.
This doesn't change the original functionality, just improve the code
maintainability and readability.
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Link: https://patch.msgid.link/20260506132152.53239-1-hui.wang@canonical.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>
compat_riscv_gpr_set() calls cregs_to_regs() unconditionally, even when
user_regset_copyin() fails. Since cregs is an uninitialized stack
variable, a copyin failure causes uninitialized stack data to be written
into the target task's pt_regs, corrupting its register state and
potentially leaking kernel stack contents.
compat_restore_sigcontext() has the same issue: it calls cregs_to_regs()
even when __copy_from_user() fails, leading to the same corruption of
the signal-returning task's register state on error.
Only call cregs_to_regs() when the user copy succeeds.
Fixes: 4608c15959 ("riscv: compat: ptrace: Add compat_arch_ptrace implement")
Fixes: 7383ee0531 ("riscv: compat: signal: Add rt_frame implementation")
Signed-off-by: Michael Neuling <mikey@neuling.org>
Assisted-by: Cursor:claude-4.6-opus-high-thinking
Link: https://patch.msgid.link/20260501062320.2339562-1-mikey@neuling.org
Signed-off-by: Paul Walmsley <pjw@kernel.org>
After commit 67bdd7b013 ("riscv: Split out measure_cycles() for
reuse") and commit c03ad15f7c ("riscv: Reuse measure_cycles() in
check_vector_unaligned_access()"), there are CFI failure when booting
kernels with CONFIG_CFI=y:
CFI failure at measure_cycles+0x38/0xe0 (target: __riscv_copy_words_unaligned+0x0/0x50; expected type: ...)
CFI failure at measure_cycles+0x38/0xe0 (target: __riscv_copy_vec_words_unaligned+0x0/0x24; expected type: ...)
The __riscv_copy_*_unaligned() functions are now called indirectly but
they are not defined with SYM_TYPED_FUNC_START, which is required for
assembly functions called indirectly from C to pass CFI checking. Switch
to SYM_TYPED_FUNC_START to clear up the CFI failures.
Fixes: 67bdd7b013 ("riscv: Split out measure_cycles() for reuse")
Fixes: c03ad15f7c ("riscv: Reuse measure_cycles() in check_vector_unaligned_access()")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Nam Cao <namcao@linutronix.de>
Link: https://patch.msgid.link/20260406-measure_cycles-cfi-failure-v1-1-03e0234ae02f@kernel.org
Signed-off-by: Paul Walmsley <pjw@kernel.org>
Pull RISC-V updates from Paul Walmsley:
"There is one significant change outside arch/riscv in this pull
request: the addition of a set of KUnit tests for strlen(), strnlen(),
and strrchr().
Otherwise, the most notable changes are to add some RISC-V-specific
string function implementations, to remove XIP kernel support, to add
hardware error exception handling, and to optimize our runtime
unaligned access speed testing.
A few comments on the motivation for removing XIP support. It's been
broken in the RISC-V kernel for months. The code is not easy to
maintain. Furthermore, for XIP support to truly be useful for RISC-V,
we think that compile-time feature switches would need to be added for
many of the RISC-V ISA features and microarchitectural properties that
are currently implemented with runtime patching. No one has stepped
forward to take responsibility for that work, so many of us think it's
best to remove it until clear use cases and champions emerge.
Summary:
- Add Kunit correctness testing and microbenchmarks for strlen(),
strnlen(), and strrchr()
- Add RISC-V-specific strnlen(), strchr(), strrchr() implementations
- Add hardware error exception handling
- Clean up and optimize our unaligned access probe code
- Enable HAVE_IOREMAP_PROT to be able to use generic_access_phys()
- Remove XIP kernel support
- Warn when addresses outside the vmemmap range are passed to
vmemmap_populate()
- Update the ACPI FADT revision check to warn if it's not at least
ACPI v6.6, which is when key RISC-V-specific tables were added to
the specification
- Increase COMMAND_LINE_SIZE to 2048 to match ARM64, x86, PowerPC,
etc.
- Make kaslr_offset() a static inline function, since there's no need
for it to show up in the symbol table
- Add KASLR offset and SATP to the VMCOREINFO ELF notes to improve
kdump support
- Add Makefile cleanup rule for vdso_cfi copied source files, and add
a .gitignore for the build artifacts in that directory
- Remove some redundant ifdefs that check Kconfig macros
- Add missing SPDX license tag to the CFI selftest
- Simplify UTS_MACHINE assignment in the RISC-V Makefile
- Clarify some unclear comments and remove some superfluous comments
- Fix various English typos across the RISC-V codebase"
* tag 'riscv-for-linus-7.1-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (31 commits)
riscv: Remove support for XIP kernel
riscv: Reuse compare_unaligned_access() in check_vector_unaligned_access()
riscv: Split out compare_unaligned_access()
riscv: Reuse measure_cycles() in check_vector_unaligned_access()
riscv: Split out measure_cycles() for reuse
riscv: Clean up & optimize unaligned scalar access probe
riscv: lib: add strrchr() implementation
riscv: lib: add strchr() implementation
riscv: lib: add strnlen() implementation
lib/string_kunit: extend benchmarks to strnlen() and chr searches
lib/string_kunit: add performance benchmark for strlen()
lib/string_kunit: add correctness test for strrchr()
lib/string_kunit: add correctness test for strnlen()
lib/string_kunit: add correctness test for strlen()
riscv: vdso_cfi: Add .gitignore for build artifacts
riscv: vdso_cfi: Add clean rule for copied sources
riscv: enable HAVE_IOREMAP_PROT
riscv: mm: WARN_ON() for bad addresses in vmemmap_populate()
riscv: acpi: update FADT revision check to 6.6
riscv: add hardware error trap handler support
...
Pull MM updates from Andrew Morton:
- "maple_tree: Replace big node with maple copy" (Liam Howlett)
Mainly prepararatory work for ongoing development but it does reduce
stack usage and is an improvement.
- "mm, swap: swap table phase III: remove swap_map" (Kairui Song)
Offers memory savings by removing the static swap_map. It also yields
some CPU savings and implements several cleanups.
- "mm: memfd_luo: preserve file seals" (Pratyush Yadav)
File seal preservation to LUO's memfd code
- "mm: zswap: add per-memcg stat for incompressible pages" (Jiayuan
Chen)
Additional userspace stats reportng to zswap
- "arch, mm: consolidate empty_zero_page" (Mike Rapoport)
Some cleanups for our handling of ZERO_PAGE() and zero_pfn
- "mm/kmemleak: Improve scan_should_stop() implementation" (Zhongqiu
Han)
A robustness improvement and some cleanups in the kmemleak code
- "Improve khugepaged scan logic" (Vernon Yang)
Improve khugepaged scan logic and reduce CPU consumption by
prioritizing scanning tasks that access memory frequently
- "Make KHO Stateless" (Jason Miu)
Simplify Kexec Handover by transitioning KHO from an xarray-based
metadata tracking system with serialization to a radix tree data
structure that can be passed directly to the next kernel
- "mm: vmscan: add PID and cgroup ID to vmscan tracepoints" (Thomas
Ballasi and Steven Rostedt)
Enhance vmscan's tracepointing
- "mm: arch/shstk: Common shadow stack mapping helper and
VM_NOHUGEPAGE" (Catalin Marinas)
Cleanup for the shadow stack code: remove per-arch code in favour of
a generic implementation
- "Fix KASAN support for KHO restored vmalloc regions" (Pasha Tatashin)
Fix a WARN() which can be emitted the KHO restores a vmalloc area
- "mm: Remove stray references to pagevec" (Tal Zussman)
Several cleanups, mainly udpating references to "struct pagevec",
which became folio_batch three years ago
- "mm: Eliminate fake head pages from vmemmap optimization" (Kiryl
Shutsemau)
Simplify the HugeTLB vmemmap optimization (HVO) by changing how tail
pages encode their relationship to the head page
- "mm/damon/core: improve DAMOS quota efficiency for core layer
filters" (SeongJae Park)
Improve two problematic behaviors of DAMOS that makes it less
efficient when core layer filters are used
- "mm/damon: strictly respect min_nr_regions" (SeongJae Park)
Improve DAMON usability by extending the treatment of the
min_nr_regions user-settable parameter
- "mm/page_alloc: pcp locking cleanup" (Vlastimil Babka)
The proper fix for a previously hotfixed SMP=n issue. Code
simplifications and cleanups ensued
- "mm: cleanups around unmapping / zapping" (David Hildenbrand)
A bunch of cleanups around unmapping and zapping. Mostly
simplifications, code movements, documentation and renaming of
zapping functions
- "support batched checking of the young flag for MGLRU" (Baolin Wang)
Batched checking of the young flag for MGLRU. It's part cleanups; one
benchmark shows large performance benefits for arm64
- "memcg: obj stock and slab stat caching cleanups" (Johannes Weiner)
memcg cleanup and robustness improvements
- "Allow order zero pages in page reporting" (Yuvraj Sakshith)
Enhance free page reporting - it is presently and undesirably order-0
pages when reporting free memory.
- "mm: vma flag tweaks" (Lorenzo Stoakes)
Cleanup work following from the recent conversion of the VMA flags to
a bitmap
- "mm/damon: add optional debugging-purpose sanity checks" (SeongJae
Park)
Add some more developer-facing debug checks into DAMON core
- "mm/damon: test and document power-of-2 min_region_sz requirement"
(SeongJae Park)
An additional DAMON kunit test and makes some adjustments to the
addr_unit parameter handling
- "mm/damon/core: make passed_sample_intervals comparisons
overflow-safe" (SeongJae Park)
Fix a hard-to-hit time overflow issue in DAMON core
- "mm/damon: improve/fixup/update ratio calculation, test and
documentation" (SeongJae Park)
A batch of misc/minor improvements and fixups for DAMON
- "mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c" (David
Hildenbrand)
Fix a possible issue with dax-device when CONFIG_HUGETLB=n. Some code
movement was required.
- "zram: recompression cleanups and tweaks" (Sergey Senozhatsky)
A somewhat random mix of fixups, recompression cleanups and
improvements in the zram code
- "mm/damon: support multiple goal-based quota tuning algorithms"
(SeongJae Park)
Extend DAMOS quotas goal auto-tuning to support multiple tuning
algorithms that users can select
- "mm: thp: reduce unnecessary start_stop_khugepaged()" (Breno Leitao)
Fix the khugpaged sysfs handling so we no longer spam the logs with
reams of junk when starting/stopping khugepaged
- "mm: improve map count checks" (Lorenzo Stoakes)
Provide some cleanups and slight fixes in the mremap, mmap and vma
code
- "mm/damon: support addr_unit on default monitoring targets for
modules" (SeongJae Park)
Extend the use of DAMON core's addr_unit tunable
- "mm: khugepaged cleanups and mTHP prerequisites" (Nico Pache)
Cleanups to khugepaged and is a base for Nico's planned khugepaged
mTHP support
- "mm: memory hot(un)plug and SPARSEMEM cleanups" (David Hildenbrand)
Code movement and cleanups in the memhotplug and sparsemem code
- "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup
CONFIG_MIGRATION" (David Hildenbrand)
Rationalize some memhotplug Kconfig support
- "change young flag check functions to return bool" (Baolin Wang)
Cleanups to change all young flag check functions to return bool
- "mm/damon/sysfs: fix memory leak and NULL dereference issues" (Josh
Law and SeongJae Park)
Fix a few potential DAMON bugs
- "mm/vma: convert vm_flags_t to vma_flags_t in vma code" (Lorenzo
Stoakes)
Convert a lot of the existing use of the legacy vm_flags_t data type
to the new vma_flags_t type which replaces it. Mainly in the vma
code.
- "mm: expand mmap_prepare functionality and usage" (Lorenzo Stoakes)
Expand the mmap_prepare functionality, which is intended to replace
the deprecated f_op->mmap hook which has been the source of bugs and
security issues for some time. Cleanups, documentation, extension of
mmap_prepare into filesystem drivers
- "mm/huge_memory: refactor zap_huge_pmd()" (Lorenzo Stoakes)
Simplify and clean up zap_huge_pmd(). Additional cleanups around
vm_normal_folio_pmd() and the softleaf functionality are performed.
* tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
mm: fix deferred split queue races during migration
mm/khugepaged: fix issue with tracking lock
mm/huge_memory: add and use has_deposited_pgtable()
mm/huge_memory: add and use normal_or_softleaf_folio_pmd()
mm: add softleaf_is_valid_pmd_entry(), pmd_to_softleaf_folio()
mm/huge_memory: separate out the folio part of zap_huge_pmd()
mm/huge_memory: use mm instead of tlb->mm
mm/huge_memory: remove unnecessary sanity checks
mm/huge_memory: deduplicate zap deposited table call
mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE()
mm/huge_memory: add a common exit path to zap_huge_pmd()
mm/huge_memory: handle buggy PMD entry in zap_huge_pmd()
mm/huge_memory: have zap_huge_pmd return a boolean, add kdoc
mm/huge: avoid big else branch in zap_huge_pmd()
mm/huge_memory: simplify vma_is_specal_huge()
mm: on remap assert that input range within the proposed VMA
mm: add mmap_action_map_kernel_pages[_full]()
uio: replace deprecated mmap hook with mmap_prepare in uio_info
drivers: hv: vmbus: replace deprecated mmap hook with mmap_prepare
mm: allow handling of stacked mmap_prepare hooks in more drivers
...
Pull ACPI support updates from Rafael Wysocki:
"These include an update of the CMOS RTC driver and the related ACPI
and x86 code that, among other things, switches it over to using the
platform device interface for device binding on x86 instead of the PNP
device driver interface (which allows the code in question to be
simplified quite a bit), a major update of the ACPI Time and Alarm
Device (TAD) driver adding an RTC class device interface to it, and
updates of core ACPI drivers that remove some unnecessary and not
really useful code from them.
Apart from that, two drivers are converted to using the platform
driver interface for device binding instead of the ACPI driver one,
which is slated for removal, support for the Performance Limited
register is added to the ACPI CPPC library and there are some
janitorial updates of it and the related cpufreq CPPC driver, the ACPI
processor driver is fixed and cleaned up, and NVIDIA vendor CPER
record handler is added to the APEI GHES code.
Also, the interface for obtaining a CPU UID from ACPI is consolidated
across architectures and used for fixing a problem with the PCI TPH
Steering Tag on ARM64, there are two updates related to ACPICA, a
minor ACPI OS Services Layer (OSL) update, and a few assorted updates
related to ACPI tables parsing.
Specifics:
- Update maintainers information regarding ACPICA (Rafael Wysocki)
- Replace strncpy() with strscpy_pad() in acpi_ut_safe_strncpy()
(Kees Cook)
- Trigger an ordered system power off after encountering a fatal
error operator in AML (Armin Wolf)
- Enable ACPI FPDT parsing on LoongArch (Xi Ruoyao)
- Remove the temporary stop-gap acpi_pptt_cache_v1_full structure
from the ACPI PPTT parser (Ben Horgan)
- Add support for exposing ACPI FPDT subtables FBPT and S3PT (Nate
DeSimone)
- Address multiple assorted issues and clean up the code in the ACPI
processor idle driver (Huisong Li)
- Replace strlcat() in the ACPI processor idle drive with a better
alternative (Andy Shevchenko)
- Rearrange and clean up acpi_processor_errata_piix4() (Rafael
Wysocki)
- Move reference performance to capabilities and fix an uninitialized
variable in the ACPI CPPC library (Pengjie Zhang)
- Add support for the Performance Limited Register to the ACPI CPPC
library (Sumit Gupta)
- Add cppc_get_perf() API to read performance controls, extend
cppc_set_epp_perf() for FFH/SystemMemory, and make the ACPI CPPC
library warn on missing mandatory DESIRED_PERF register (Sumit
Gupta)
- Modify the cpufreq CPPC driver to update MIN_PERF/MAX_PERF in
target callbacks to allow it to control performance bounds via
standard scaling_min_freq and scaling_max_freq sysfs attributes and
add sysfs documentation for the Performance Limited Register to it
(Sumit Gupta)
- Add ACPI support to the platform device interface in the CMOS RTC
driver, make the ACPI core device enumeration code create a
platform device for the CMOS RTC, and drop CMOS RTC PNP device
support (Rafael Wysocki)
- Consolidate the x86-specific CMOS RTC handling with the ACPI TAD
driver and clean up the CMOS RTC ACPI address space handler (Rafael
Wysocki)
- Enable ACPI alarm in the CMOS RTC driver if advertised in ACPI FADT
and allow that driver to work without a dedicated IRQ if the ACPI
alarm is used (Rafael Wysocki)
- Clean up the ACPI TAD driver in various ways and add an RTC class
device interface, including both the RTC setting/reading and alarm
timer support, to it (Rafael Wysocki)
- Clean up the ACPI AC and ACPI PAD (processor aggregator device)
drivers (Rafael Wysocki)
- Rework checking for duplicate video bus devices and consolidate
pnp.bus_id workarounds handling in the ACPI video bus driver
(Rafael Wysocki)
- Update the ACPI core device drivers to stop setting
acpi_device_name() unnecessarily (Rafael Wysocki)
- Rearrange code using acpi_device_class() in the ACPI core device
drivers and update them to stop setting acpi_device_class()
unnecessarily (Rafael Wysocki)
- Define ACPI_AC_CLASS in one place (Rafael Wysocki)
- Convert the ni903x_wdt watchdog driver and the xen ACPI PAD driver
to bind to platform devices instead of ACPI devices (Rafael
Wysocki)
- Add devm_ghes_register_vendor_record_notifier(), use it in the PCI
hisi driver, and Add NVIDIA vendor CPER record handler (Kai-Heng
Feng)
- Consolidate the interface for obtaining a CPU UID from ACPI across
architectures and use it to address incorrect PCI TPH Steering Tag
on ARM64 resulting from the invalid assumption that the ACPI
Processor UID would always be the same as the corresponding logical
CPU ID in Linux (Chengwen Feng)"
* tag 'acpi-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (73 commits)
ACPICA: Update maintainers information
watchdog: ni903x_wdt: Convert to a platform driver
ACPI: PAD: xen: Convert to a platform driver
ACPI: processor: idle: Reset cpuidle on C-state list changes
cpuidle: Extract and export no-lock variants of cpuidle_unregister_device()
PCI/TPH: Pass ACPI Processor UID to Cache Locality _DSM
ACPI: PPTT: Use acpi_get_cpu_uid() and remove get_acpi_id_for_cpu()
perf: arm_cspmu: Switch to acpi_get_cpu_uid() from get_acpi_id_for_cpu()
ACPI: Centralize acpi_get_cpu_uid() declaration in include/linux/acpi.h
x86/acpi: Add acpi_get_cpu_uid() for unified ACPI CPU UID retrieval
RISC-V: ACPI: Add acpi_get_cpu_uid() for unified ACPI CPU UID retrieval
LoongArch: Add acpi_get_cpu_uid() for unified ACPI CPU UID retrieval
arm64: acpi: Add acpi_get_cpu_uid() for unified ACPI CPU UID retrieval
ACPI: APEI: GHES: Add NVIDIA vendor CPER record handler
PCI: hisi: Use devm_ghes_register_vendor_record_notifier()
ACPI: APEI: GHES: Add devm_ghes_register_vendor_record_notifier()
ACPI: tables: Enable FPDT on LoongArch
ACPI: processor: idle: Fix NULL pointer dereference in hotplug path
ACPI: processor: idle: Reset power_setup_done flag on initialization failure
ACPI: TAD: Add alarm support to the RTC class device interface
...
Pull hardening updates from Kees Cook:
- randomize_kstack: Improve implementation across arches (Ryan Roberts)
- lkdtm/fortify: Drop unneeded FORTIFY_STR_OBJECT test
- refcount: Remove unused __signed_wrap function annotations
* tag 'hardening-v7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
lkdtm/fortify: Drop unneeded FORTIFY_STR_OBJECT test
refcount: Remove unused __signed_wrap function annotations
randomize_kstack: Unify random source across arches
randomize_kstack: Maintain kstack_offset per task
check_unaligned_access_speed_all_cpus() is more complicated than it should
be:
- It uses on_each_cpu() to probe unaligned memory access on all CPUs but
excludes CPU0 with a check in the callback function. So an IPI to CPU0
is wasted.
- Probing on CPU0 is done with smp_call_on_cpu(), which is not as fast as
on_each_cpu().
The reason for this design is because the probe is timed with jiffies.
Therefore on_each_cpu() excludes CPU0 because that CPU needs to tend to
jiffies.
Instead, replace jiffies usage with ktime_get_mono_fast_ns(). With jiffies
out of the way, on_each_cpu() can be used for all CPUs and
smp_call_on_cpu() can be dropped.
To make ktime_get_mono_fast_ns() usable, move this probe to late_initcall.
Anything after clocksource's fs_initcall works, but avoid depending on
clocksource staying at fs_initcall.
The choice of probe time is now 8000000 ns, which is the same as before (2
jiffies) for riscv defconfig. This is excessive for the CPUs I have, and
probably should be reduced; but that's a different discussion.
Suggested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Link: https://patch.msgid.link/9b9a20affe2e4f5c380926ceb885a47e20a59395.1770830596.git.namcao@linutronix.de
Signed-off-by: Paul Walmsley <pjw@kernel.org>
The vdso_cfi build process copies source files (*.c, *.S) from the main
vdso directory to the build directory. Without a .gitignore file, these
copied files appear as untracked files in git status, cluttering the
working directory.
Add a .gitignore file to exclude:
- Copied source files (*.c, *.S)
- Temporary build files (vdso.lds, *.tmp, vdso-syms.S)
- While preserving vdso-cfi.S which is the original entry point
This follows the same pattern used in the main vdso directory
and keeps the working directory clean.
Signed-off-by: Chen Pei <cp0613@linux.alibaba.com>
Link: https://patch.msgid.link/20260320021850.1877-3-cp0613@linux.alibaba.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>
When building VDSO with CFI support, source files are copied from the main
VDSO directory to the CFI build directory as part of the build process.
However, these copied source files were not removed during 'make clean',
leaving temporary files in the build directory.
Add the clean-files variable to ensure that these copied .c and .S files
are properly cleaned up. The notdir() function is used to strip the path
prefix, as clean-files expects relative file names without directory
components.
This ensures the build directory is left in a clean state after make clean.
Signed-off-by: Chen Pei <cp0613@linux.alibaba.com>
Link: https://patch.msgid.link/20260320021850.1877-2-cp0613@linux.alibaba.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>
Add support for handling hardware error traps (exception code 19)
in the RISC-V architecture. The changes include:
- Add do_trap_hardware_error function declaration in asm-prototypes.h
- Add hardware error trap vector entry in entry.S exception vector table
- Implement do_trap_hardware_error handler in traps.c that generates
SIGBUS with BUS_MCEERR_AR for hardware errors
This enables proper handling of hardware error exceptions that may occur
in RISC-V systems, providing appropriate error reporting and signal
generation for user space processes.
Signed-off-by: Rui Qi <qirui.001@bytedance.com>
Link: https://patch.msgid.link/20260202094200.53735-1-qirui.001@bytedance.com
[pjw@kernel.org: clean up commit message slightly]
Signed-off-by: Paul Walmsley <pjw@kernel.org>
The following options are required by the kdump crash utility for RISC-V
based vmcore file:
- kaslr: If the vmcore is generated from a KASLR-enabled Linux kernel,
the KASLR offset is required for the crash utility to load
the vmcore. Without the proper kaslr option, the crash utility
fails to load the vmcore file.
- satp: The exact root page table address helps determine the correct base
PGD address.
With this patch, RISC-V VMCOREINFO ELF notes now include both kaslr
and satp information.
Signed-off-by: Austin Kim <austin.kim@lge.com>
Link: https://patch.msgid.link/aYwKUE3ZzN7/ZY/A@adminpc-PowerEdge-R7525
Signed-off-by: Paul Walmsley <pjw@kernel.org>