linux.git/arch/arm/kernel, branch v6.1.168

PCI: Introduce pci_dev_for_each_resource()

2026-03-25T10:02:54+00:00

[ Upstream commit 09cc900632400079619e9154604fd299c2cc9a5a ]

Instead of open-coding it everywhere introduce a tiny helper that can be
used to iterate over each resource of a PCI device, and convert the most
obvious users into it.

While at it drop doubled empty line before pdev_sort_resources().

No functional changes intended.

Suggested-by: Andy Shevchenko 
Link: https://lore.kernel.org/r/20230330162434.35055-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Mika Westerberg 
Signed-off-by: Andy Shevchenko 
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Krzysztof Wilczyński 
Stable-dep-of: 11721c45a826 ("PCI: Use resource_set_range() that correctly sets ->end")
Signed-off-by: Sasha Levin

ARM: VDSO: Patch out __vdso_clock_getres() if unavailable

2026-03-04T12:19:26+00:00

[ Upstream commit b9fecf0dddfc55cd7d02b0011494da3c613f7cde ]

The vDSO code hides symbols which are non-functional.
__vdso_clock_getres() was not added to this list when it got introduced.

Fixes: 052e76a31b4a ("ARM: 8931/1: Add clock_getres entry point")
Signed-off-by: Thomas Weißschuh 
Signed-off-by: Thomas Gleixner 
Link: https://patch.msgid.link/20251223-vdso-compat-time32-v1-6-97ea7a06a543@linutronix.de
Signed-off-by: Sasha Levin

arch: Add the macro COMPILE_OFFSETS to all the asm-offsets.c

2025-12-06T21:12:09+00:00

[ Upstream commit 35561bab768977c9e05f1f1a9bc00134c85f3e28 ]

The include/generated/asm-offsets.h is generated in Kbuild during
compiling from arch/SRCARCH/kernel/asm-offsets.c. When we want to
generate another similar offset header file, circular dependency can
happen.

For example, we want to generate a offset file include/generated/test.h,
which is included in include/sched/sched.h. If we generate asm-offsets.h
first, it will fail, as include/sched/sched.h is included in asm-offsets.c
and include/generated/test.h doesn't exist; If we generate test.h first,
it can't success neither, as include/generated/asm-offsets.h is included
by it.

In x86_64, the macro COMPILE_OFFSETS is used to avoid such circular
dependency. We can generate asm-offsets.h first, and if the
COMPILE_OFFSETS is defined, we don't include the "generated/test.h".

And we define the macro COMPILE_OFFSETS for all the asm-offsets.c for this
purpose.

Signed-off-by: Menglong Dong 
Signed-off-by: Peter Zijlstra (Intel) 
Signed-off-by: Sasha Levin

ARM: 9430/1: entry: Do a dummy read from VMAP shadow

2024-12-14T18:54:14+00:00

commit 44e9a3bb76e5f2eecd374c8176b2c5163c8bb2e2 upstream.

When switching task, in addition to a dummy read from the new
VMAP stack, also do a dummy read from the VMAP stack's
corresponding KASAN shadow memory to sync things up in
the new MM context.

Cc: stable@vger.kernel.org
Fixes: a1c510d0adc6 ("ARM: implement support for vmap'ed stacks")
Link: https://lore.kernel.org/linux-arm-kernel/a1a1d062-f3a2-4d05-9836-3b098de9db6d@foss.st.com/
Reported-by: Clement LE GOFFIC 
Suggested-by: Ard Biesheuvel 
Signed-off-by: Linus Walleij 
Signed-off-by: Russell King (Oracle) 
Signed-off-by: Greg Kroah-Hartman

ARM: 9420/1: smp: Fix SMP for xip kernels

2024-12-14T18:53:11+00:00

[ Upstream commit 9e9b0cf9319b4db143014477b0bc4b39894248f1 ]

Fix the physical address calculation of the following to get smp working
on xip kernels.
- secondary_data needed for secondary cpu bootup.
- secondary_startup address passed through psci.
- identity mapped code region needed for enabling mmu for secondary cpus.

Signed-off-by: Harith George 
Reviewed-by: Linus Walleij 
Signed-off-by: Russell King (Oracle) 
Signed-off-by: Sasha Levin

ARM: 9419/1: mm: Fix kernel memory mapping for xip kernels

2024-11-22T14:37:30+00:00

[ Upstream commit ed6cbe6e5563452f305e89c15846820f2874e431 ]

The patchset introducing kernel_sec_start/end variables to separate the
kernel/lowmem memory mappings, broke the mapping of the kernel memory
for xipkernels.

kernel_sec_start/end variables are in RO area before the MMU is switched
on for xipkernels.
So these cannot be set early in boot in head.S. Fix this by setting these
after MMU is switched on.
xipkernels need two different mappings for kernel text (starting at
CONFIG_XIP_PHYS_ADDR) and data (starting at CONFIG_PHYS_OFFSET).
Also, move the kernel code mapping from devicemaps_init() to map_kernel().

Fixes: a91da5457085 ("ARM: 9089/1: Define kernel physical section start and end")
Signed-off-by: Harith George 
Reviewed-by: Linus Walleij 
Signed-off-by: Russell King (Oracle) 
Signed-off-by: Sasha Levin

ARM: 9381/1: kasan: clear stale stack poison

2024-05-17T09:56:10+00:00

[ Upstream commit c4238686f9093b98bd6245a348bcf059cdce23af ]

We found below OOB crash:

[   33.452494] ==================================================================
[   33.453513] BUG: KASAN: stack-out-of-bounds in refresh_cpu_vm_stats.constprop.0+0xcc/0x2ec
[   33.454660] Write of size 164 at addr c1d03d30 by task swapper/0/0
[   33.455515]
[   33.455767] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G           O       6.1.25-mainline #1
[   33.456880] Hardware name: Generic DT based system
[   33.457555]  unwind_backtrace from show_stack+0x18/0x1c
[   33.458326]  show_stack from dump_stack_lvl+0x40/0x4c
[   33.459072]  dump_stack_lvl from print_report+0x158/0x4a4
[   33.459863]  print_report from kasan_report+0x9c/0x148
[   33.460616]  kasan_report from kasan_check_range+0x94/0x1a0
[   33.461424]  kasan_check_range from memset+0x20/0x3c
[   33.462157]  memset from refresh_cpu_vm_stats.constprop.0+0xcc/0x2ec
[   33.463064]  refresh_cpu_vm_stats.constprop.0 from tick_nohz_idle_stop_tick+0x180/0x53c
[   33.464181]  tick_nohz_idle_stop_tick from do_idle+0x264/0x354
[   33.465029]  do_idle from cpu_startup_entry+0x20/0x24
[   33.465769]  cpu_startup_entry from rest_init+0xf0/0xf4
[   33.466528]  rest_init from arch_post_acpi_subsys_init+0x0/0x18
[   33.467397]
[   33.467644] The buggy address belongs to stack of task swapper/0/0
[   33.468493]  and is located at offset 112 in frame:
[   33.469172]  refresh_cpu_vm_stats.constprop.0+0x0/0x2ec
[   33.469917]
[   33.470165] This frame has 2 objects:
[   33.470696]  [32, 76) 'global_zone_diff'
[   33.470729]  [112, 276) 'global_node_diff'
[   33.471294]
[   33.472095] The buggy address belongs to the physical page:
[   33.472862] page:3cd72da8 refcount:1 mapcount:0 mapping:00000000 index:0x0 pfn:0x41d03
[   33.473944] flags: 0x1000(reserved|zone=0)
[   33.474565] raw: 00001000 ed741470 ed741470 00000000 00000000 00000000 ffffffff 00000001
[   33.475656] raw: 00000000
[   33.476050] page dumped because: kasan: bad access detected
[   33.476816]
[   33.477061] Memory state around the buggy address:
[   33.477732]  c1d03c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[   33.478630]  c1d03c80: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00 00
[   33.479526] >c1d03d00: 00 04 f2 f2 f2 f2 00 00 00 00 00 00 f1 f1 f1 f1
[   33.480415]                                                ^
[   33.481195]  c1d03d80: 00 00 00 00 00 00 00 00 00 00 04 f3 f3 f3 f3 f3
[   33.482088]  c1d03e00: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
[   33.482978] ==================================================================

We find the root cause of this OOB is that arm does not clear stale stack
poison in the case of cpuidle.

This patch refer to arch/arm64/kernel/sleep.S to resolve this issue.

From cited commit [1] that explain the problem

Functions which the compiler has instrumented for KASAN place poison on
the stack shadow upon entry and remove this poison prior to returning.

In the case of cpuidle, CPUs exit the kernel a number of levels deep in
C code.  Any instrumented functions on this critical path will leave
portions of the stack shadow poisoned.

If CPUs lose context and return to the kernel via a cold path, we
restore a prior context saved in __cpu_suspend_enter are forgotten, and
we never remove the poison they placed in the stack shadow area by
functions calls between this and the actual exit of the kernel.

Thus, (depending on stackframe layout) subsequent calls to instrumented
functions may hit this stale poison, resulting in (spurious) KASAN
splats to the console.

To avoid this, clear any stale poison from the idle thread for a CPU
prior to bringing a CPU online.

From cited commit [2]

Extend to check for CONFIG_KASAN_STACK

[1] commit 0d97e6d8024c ("arm64: kasan: clear stale stack poison")
[2] commit d56a9ef84bd0 ("kasan, arm64: unpoison stack only with CONFIG_KASAN_STACK")

Signed-off-by: Boy Wu 
Reviewed-by: Mark Rutland 
Acked-by: Andrey Ryabinin 
Reviewed-by: Linus Walleij 
Fixes: 5615f69bc209 ("ARM: 9016/2: Initialize the mapping of KASan shadow memory")
Signed-off-by: Russell King (Oracle) 
Signed-off-by: Sasha Levin

ARM: 9317/1: kexec: Make smp stop calls asynchronous

2023-09-23T09:11:05+00:00

[ Upstream commit 8922ba71c969d2a0c01a94372a71477d879470de ]

If a panic is triggered by a hrtimer interrupt all online cpus will be
notified and set offline. But as highlighted by commit 19dbdcb8039c
("smp: Warn on function calls from softirq context") this call should
not be made synchronous with disabled interrupts:

 softdog: Initiating panic
 Kernel panic - not syncing: Software Watchdog Timer expired
 WARNING: CPU: 1 PID: 0 at kernel/smp.c:753 smp_call_function_many_cond
   unwind_backtrace:
     show_stack
     dump_stack_lvl
     __warn
     warn_slowpath_fmt
     smp_call_function_many_cond
     smp_call_function
     crash_smp_send_stop.part.0
     machine_crash_shutdown
     __crash_kexec
     panic
     softdog_fire
     __hrtimer_run_queues
     hrtimer_interrupt

Make the smp call for machine_crash_nonpanic_core() asynchronous.

Signed-off-by: Mårten Lindahl 
Signed-off-by: Russell King (Oracle) 
Signed-off-by: Sasha Levin

hw_breakpoint: fix single-stepping when using bpf_overflow_handler

2023-09-23T09:11:00+00:00

[ Upstream commit d11a69873d9a7435fe6a48531e165ab80a8b1221 ]

Arm platforms use is_default_overflow_handler() to determine if the
hw_breakpoint code should single-step over the breakpoint trigger or
let the custom handler deal with it.

Since bpf_overflow_handler() currently isn't recognized as a default
handler, attaching a BPF program to a PERF_TYPE_BREAKPOINT event causes
it to keep firing (the instruction triggering the data abort exception
is never skipped). For example:

  # bpftrace -e 'watchpoint:0x10000:4:w { print("hit") }' -c ./test
  Attaching 1 probe...
  hit
  hit
  [...]
  ^C

(./test performs a single 4-byte store to 0x10000)

This patch replaces the check with uses_default_overflow_handler(),
which accounts for the bpf_overflow_handler() case by also testing
if one of the perf_event_output functions gets invoked indirectly,
via orig_default_handler.

Signed-off-by: Tomislav Novak 
Tested-by: Samuel Gosselin  # arm64
Reviewed-by: Catalin Marinas 
Acked-by: Alexei Starovoitov 
Link: https://lore.kernel.org/linux-arm-kernel/20220923203644.2731604-1-tnovak@fb.com/
Link: https://lore.kernel.org/r/20230605191923.1219974-1-tnovak@meta.com
Signed-off-by: Will Deacon 
Signed-off-by: Sasha Levin

ARM: ptrace: Restore syscall skipping for tracers

2023-09-13T07:42:28+00:00

[ Upstream commit 4697b5848bd933f68ebd04836362c8de0cacaf71 ]

Since commit 4e57a4ddf6b0 ("ARM: 9107/1: syscall: always store
thread_info->abi_syscall"), the seccomp selftests "syscall_errno"
and "syscall_faked" have been broken. Both seccomp and PTRACE depend
on using the special value of "-1" for skipping syscalls. This value
wasn't working because it was getting masked by __NR_SYSCALL_MASK in
both PTRACE_SET_SYSCALL and get_syscall_nr().

Explicitly test for -1 in PTRACE_SET_SYSCALL and get_syscall_nr(),
leaving it exposed when present, allowing tracers to skip syscalls
again.

Cc: Russell King 
Cc: Arnd Bergmann 
Cc: Lecopzer Chen 
Cc: Oleg Nesterov 
Cc: linux-arm-kernel@lists.infradead.org
Fixes: 4e57a4ddf6b0 ("ARM: 9107/1: syscall: always store thread_info->abi_syscall")
Reviewed-by: Arnd Bergmann 
Link: https://lore.kernel.org/r/20230810195422.2304827-2-keescook@chromium.org
Signed-off-by: Kees Cook 
Signed-off-by: Sasha Levin