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block: fix atomic write limits for stacked devices#11

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block: fix atomic write limits for stacked devices#11
blktests-ci[bot] wants to merge 2 commits intolinus-master_basefrom
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@blktests-ci blktests-ci Bot commented Jun 10, 2025

Pull request for series with
subject: block: fix atomic write limits for stacked devices
version: 1
url: https://patchwork.kernel.org/project/linux-block/list/?series=968265

kawasaki and others added 2 commits June 9, 2025 20:58
The current logic applies the bottom device's atomic write limits to
the stacked (top) device only if the top device does not support chunk
sectors. However, this approach is too restrictive.

We should also propagate the bottom device's atomic write limits to the
stacked device if atomic_write_hw_unit_{min,max} of the bottom device
are aligned with the top device's chunk size (io_min). Failing to do so
may unnecessarily reduce the stacked device's atomic write limits to
values much smaller than what the hardware can actually support.

For example, on an NVMe disk with the following controller capability:
$ nvme id-ctrl /dev/nvme1  | grep awupf
awupf     : 63

Without the patch applied,

The bottom device (nvme1c1n1) atomic queue limits:
$ /sys/block/nvme1c1n1/queue/atomic_write_boundary_bytes:0
$ /sys/block/nvme1c1n1/queue/atomic_write_max_bytes:262144
$ /sys/block/nvme1c1n1/queue/atomic_write_unit_max_bytes:262144
$ /sys/block/nvme1c1n1/queue/atomic_write_unit_min_bytes:4096

The top device (nvme1n1) atomic queue limits:
$ /sys/block/nvme1n1/queue/atomic_write_boundary_bytes:0
$ /sys/block/nvme1n1/queue/atomic_write_max_bytes:4096
$ /sys/block/nvme1n1/queue/atomic_write_unit_max_bytes:4096
$ /sys/block/nvme1n1/queue/atomic_write_unit_min_bytes:4096

With this patch applied,

The top device (nvme1n1) atomic queue limits:
/sys/block/nvme1n1/queue/atomic_write_boundary_bytes:0
/sys/block/nvme1n1/queue/atomic_write_max_bytes:262144
/sys/block/nvme1n1/queue/atomic_write_unit_max_bytes:262144
/sys/block/nvme1n1/queue/atomic_write_unit_min_bytes:4096

This change ensures that the stacked device retains optimal atomic write
capability when alignment permits, improving overall performance and
correctness.

Reported-by: Ojaswin Mujoo <[email protected]>
Fixes: d7f36dc ("block: Support atomic writes limits for stacked devices")
Signed-off-by: Nilay Shroff <[email protected]>
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blktests-ci Bot commented Jun 10, 2025

Upstream branch: 19272b3
series: https://patchwork.kernel.org/project/linux-block/list/?series=968265
version: 1

blktests-ci Bot pushed a commit that referenced this pull request Jul 10, 2025
…th()

KASAN reports a stack-out-of-bounds read in regs_get_kernel_stack_nth().

Call Trace:
[   97.283505] BUG: KASAN: stack-out-of-bounds in regs_get_kernel_stack_nth+0xa8/0xc8
[   97.284677] Read of size 8 at addr ffff800089277c10 by task 1.sh/2550
[   97.285732]
[   97.286067] CPU: 7 PID: 2550 Comm: 1.sh Not tainted 6.6.0+ #11
[   97.287032] Hardware name: linux,dummy-virt (DT)
[   97.287815] Call trace:
[   97.288279]  dump_backtrace+0xa0/0x128
[   97.288946]  show_stack+0x20/0x38
[   97.289551]  dump_stack_lvl+0x78/0xc8
[   97.290203]  print_address_description.constprop.0+0x84/0x3c8
[   97.291159]  print_report+0xb0/0x280
[   97.291792]  kasan_report+0x84/0xd0
[   97.292421]  __asan_load8+0x9c/0xc0
[   97.293042]  regs_get_kernel_stack_nth+0xa8/0xc8
[   97.293835]  process_fetch_insn+0x770/0xa30
[   97.294562]  kprobe_trace_func+0x254/0x3b0
[   97.295271]  kprobe_dispatcher+0x98/0xe0
[   97.295955]  kprobe_breakpoint_handler+0x1b0/0x210
[   97.296774]  call_break_hook+0xc4/0x100
[   97.297451]  brk_handler+0x24/0x78
[   97.298073]  do_debug_exception+0xac/0x178
[   97.298785]  el1_dbg+0x70/0x90
[   97.299344]  el1h_64_sync_handler+0xcc/0xe8
[   97.300066]  el1h_64_sync+0x78/0x80
[   97.300699]  kernel_clone+0x0/0x500
[   97.301331]  __arm64_sys_clone+0x70/0x90
[   97.302084]  invoke_syscall+0x68/0x198
[   97.302746]  el0_svc_common.constprop.0+0x11c/0x150
[   97.303569]  do_el0_svc+0x38/0x50
[   97.304164]  el0_svc+0x44/0x1d8
[   97.304749]  el0t_64_sync_handler+0x100/0x130
[   97.305500]  el0t_64_sync+0x188/0x190
[   97.306151]
[   97.306475] The buggy address belongs to stack of task 1.sh/2550
[   97.307461]  and is located at offset 0 in frame:
[   97.308257]  __se_sys_clone+0x0/0x138
[   97.308910]
[   97.309241] This frame has 1 object:
[   97.309873]  [48, 184) 'args'
[   97.309876]
[   97.310749] The buggy address belongs to the virtual mapping at
[   97.310749]  [ffff800089270000, ffff800089279000) created by:
[   97.310749]  dup_task_struct+0xc0/0x2e8
[   97.313347]
[   97.313674] The buggy address belongs to the physical page:
[   97.314604] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x14f69a
[   97.315885] flags: 0x15ffffe00000000(node=1|zone=2|lastcpupid=0xfffff)
[   97.316957] raw: 015ffffe00000000 0000000000000000 dead000000000122 0000000000000000
[   97.318207] raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
[   97.319445] page dumped because: kasan: bad access detected
[   97.320371]
[   97.320694] Memory state around the buggy address:
[   97.321511]  ffff800089277b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[   97.322681]  ffff800089277b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[   97.323846] >ffff800089277c00: 00 00 f1 f1 f1 f1 f1 f1 00 00 00 00 00 00 00 00
[   97.325023]                          ^
[   97.325683]  ffff800089277c80: 00 00 00 00 00 00 00 00 00 f3 f3 f3 f3 f3 f3 f3
[   97.326856]  ffff800089277d00: f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00

This issue seems to be related to the behavior of some gcc compilers and
was also fixed on the s390 architecture before:

 commit d93a855 ("s390/ptrace: Avoid KASAN false positives in regs_get_kernel_stack_nth()")

As described in that commit, regs_get_kernel_stack_nth() has confirmed that
`addr` is on the stack, so reading the value at `*addr` should be allowed.
Use READ_ONCE_NOCHECK() helper to silence the KASAN check for this case.

Fixes: 0a8ea52 ("arm64: Add HAVE_REGS_AND_STACK_ACCESS_API feature")
Signed-off-by: Tengda Wu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[will: Use '*addr' as the argument to READ_ONCE_NOCHECK()]
Signed-off-by: Will Deacon <[email protected]>
blktests-ci Bot pushed a commit that referenced this pull request Jul 10, 2025
Since commit 6b9f29b ("riscv: Enable pcpu page first chunk
allocator"), if NUMA is enabled, the page percpu allocator may be used
on very sparse configurations, or when requested on boot with
percpu_alloc=page.

In that case, percpu data gets put in the vmalloc area. However,
sbi_hsm_hart_start() needs the physical address of a sbi_hart_boot_data,
and simply assumes that __pa() would work. This causes the just started
hart to immediately access an invalid address and hang.

Fortunately, struct sbi_hart_boot_data is not too large, so we can
simply allocate an array for boot_data statically, putting it in the
kernel image.

This fixes NUMA=y SMP boot on Sophgo SG2042.

To reproduce on QEMU: Set CONFIG_NUMA=y and CONFIG_DEBUG_VIRTUAL=y, then
run with:

  qemu-system-riscv64 -M virt -smp 2 -nographic \
    -kernel arch/riscv/boot/Image \
    -append "percpu_alloc=page"

Kernel output:

[    0.000000] Booting Linux on hartid 0
[    0.000000] Linux version 6.16.0-rc1 (dram@sakuya) (riscv64-unknown-linux-gnu-gcc (GCC) 14.2.1 20250322, GNU ld (GNU Binutils) 2.44) #11 SMP Tue Jun 24 14:56:22 CST 2025
...
[    0.000000] percpu: 28 4K pages/cpu s85784 r8192 d20712
...
[    0.083192] smp: Bringing up secondary CPUs ...
[    0.086722] ------------[ cut here ]------------
[    0.086849] virt_to_phys used for non-linear address: (____ptrval____) (0xff2000000001d080)
[    0.088001] WARNING: CPU: 0 PID: 1 at arch/riscv/mm/physaddr.c:14 __virt_to_phys+0xae/0xe8
[    0.088376] Modules linked in:
[    0.088656] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.16.0-rc1 #11 NONE
[    0.088833] Hardware name: riscv-virtio,qemu (DT)
[    0.088948] epc : __virt_to_phys+0xae/0xe8
[    0.089001]  ra : __virt_to_phys+0xae/0xe8
[    0.089037] epc : ffffffff80021eaa ra : ffffffff80021eaa sp : ff2000000004bbc0
[    0.089057]  gp : ffffffff817f49c0 tp : ff60000001d60000 t0 : 5f6f745f74726976
[    0.089076]  t1 : 0000000000000076 t2 : 705f6f745f747269 s0 : ff2000000004bbe0
[    0.089095]  s1 : ff2000000001d080 a0 : 0000000000000000 a1 : 0000000000000000
[    0.089113]  a2 : 0000000000000000 a3 : 0000000000000000 a4 : 0000000000000000
[    0.089131]  a5 : 0000000000000000 a6 : 0000000000000000 a7 : 0000000000000000
[    0.089155]  s2 : ffffffff8130dc00 s3 : 0000000000000001 s4 : 0000000000000001
[    0.089174]  s5 : ffffffff8185eff8 s6 : ff2000007f1eb000 s7 : ffffffff8002a2ec
[    0.089193]  s8 : 0000000000000001 s9 : 0000000000000001 s10: 0000000000000000
[    0.089211]  s11: 0000000000000000 t3 : ffffffff8180a9f7 t4 : ffffffff8180a9f7
[    0.089960]  t5 : ffffffff8180a9f8 t6 : ff2000000004b9d8
[    0.089984] status: 0000000200000120 badaddr: ffffffff80021eaa cause: 0000000000000003
[    0.090101] [<ffffffff80021eaa>] __virt_to_phys+0xae/0xe8
[    0.090228] [<ffffffff8001d796>] sbi_cpu_start+0x6e/0xe8
[    0.090247] [<ffffffff8001a5da>] __cpu_up+0x1e/0x8c
[    0.090260] [<ffffffff8002a32e>] bringup_cpu+0x42/0x258
[    0.090277] [<ffffffff8002914c>] cpuhp_invoke_callback+0xe0/0x40c
[    0.090292] [<ffffffff800294e0>] __cpuhp_invoke_callback_range+0x68/0xfc
[    0.090320] [<ffffffff8002a96a>] _cpu_up+0x11a/0x244
[    0.090334] [<ffffffff8002aae6>] cpu_up+0x52/0x90
[    0.090384] [<ffffffff80c09350>] bringup_nonboot_cpus+0x78/0x118
[    0.090411] [<ffffffff80c11060>] smp_init+0x34/0xb8
[    0.090425] [<ffffffff80c01220>] kernel_init_freeable+0x148/0x2e4
[    0.090442] [<ffffffff80b83802>] kernel_init+0x1e/0x14c
[    0.090455] [<ffffffff800124ca>] ret_from_fork_kernel+0xe/0xf0
[    0.090471] [<ffffffff80b8d9c2>] ret_from_fork_kernel_asm+0x16/0x18
[    0.090560] ---[ end trace 0000000000000000 ]---
[    1.179875] CPU1: failed to come online
[    1.190324] smp: Brought up 1 node, 1 CPU

Cc: [email protected]
Reported-by: Han Gao <[email protected]>
Fixes: 6b9f29b ("riscv: Enable pcpu page first chunk allocator")
Reviewed-by: Alexandre Ghiti <[email protected]>
Tested-by: Alexandre Ghiti <[email protected]>
Signed-off-by: Vivian Wang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Ghiti <[email protected]>
@blktests-ci blktests-ci Bot force-pushed the linus-master_base branch from 3d460ec to ac8b12e Compare July 10, 2025 11:56
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blktests-ci Bot commented Jul 10, 2025

At least one diff in series https://patchwork.kernel.org/project/linux-block/list/?series=968265 irrelevant now for [{'archived': False, 'project': 241}] search patterns

@blktests-ci blktests-ci Bot closed this Jul 10, 2025
@blktests-ci blktests-ci Bot deleted the series/968265=>linus-master branch July 23, 2025 02:17
blktests-ci Bot pushed a commit that referenced this pull request Jul 31, 2025
cmpxchg_user_key() may be executed with a non-zero key; if then the storage
key of the page which belongs to the cmpxchg_user_key() code contains a key
with fetch-protection enabled the result is a protection exception:

Unable to handle kernel pointer dereference in virtual kernel address space
Failing address: 0000000000000000 TEID: 000000000000080b
Fault in home space mode while using kernel ASCE.
AS:0000000002528007 R3:00000001ffffc007 S:00000001ffffb801 P:000000000000013d
Oops: 0004 ilc:1 [#1]SMP
Modules linked in:
CPU: 3 UID: 0 PID: 791 Comm: memop Not tainted 6.16.0-rc1-00006-g3b568201d0a6-dirty #11 NONE
Hardware name: IBM 3931 A01 704 (z/VM 7.4.0)
Krnl PSW : 0794f00180000000 000003ffe0f4d91e (__cmpxchg_user_key1+0xbe/0x190)
           R:0 T:1 IO:1 EX:1 Key:9 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
Krnl GPRS: 070003ffdfbf6af0 0000000000070000 0000000095b5a300 0000000000000000
           00000000f1000000 0000000000000000 0000000000000090 0000000000000000
           0000000000000040 0000000000000018 000003ff9b23d000 0000037fe0ef7bd8
           000003ffdfbf7500 00000000962e4000 0000037f00ffffff 0000037fe0ef7aa0
Krnl Code: 000003ffe0f4d912: ad03f0a0            stosm   160(%r15),3
           000003ffe0f4d916: a7780000            lhi     %r7,0
          #000003ffe0f4d91a: b20a6000            spka    0(%r6)
          >000003ffe0f4d91e: b2790100            sacf    256
           000003ffe0f4d922: a56f0080            llill   %r6,128
           000003ffe0f4d926: 5810a000            l       %r1,0(%r10)
           000003ffe0f4d92a: 141e                nr      %r1,%r14
           000003ffe0f4d92c: c0e7ffffffff        xilf    %r14,4294967295
Call Trace:
 [<000003ffe0f4d91e>] __cmpxchg_user_key1+0xbe/0x190
 [<000003ffe0189c6e>] cmpxchg_guest_abs_with_key+0x2fe/0x370
 [<000003ffe016d28e>] kvm_s390_vm_mem_op_cmpxchg+0x17e/0x350
 [<000003ffe0173284>] kvm_arch_vm_ioctl+0x354/0x6f0
 [<000003ffe015fedc>] kvm_vm_ioctl+0x2cc/0x6e0
 [<000003ffe05348ae>] vfs_ioctl+0x2e/0x70
 [<000003ffe0535e70>] __s390x_sys_ioctl+0xe0/0x100
 [<000003ffe0f40f06>] __do_syscall+0x136/0x340
 [<000003ffe0f4cb2e>] system_call+0x6e/0x90
Last Breaking-Event-Address:
 [<000003ffe0f4d896>] __cmpxchg_user_key1+0x36/0x190

Fix this by defining all code ranges within cmpxchg_user_key() functions
which may be executed with a non-default key and explicitly initialize
storage keys by calling skey_regions_initialize().

Reviewed-by: Claudio Imbrenda <[email protected]>
Signed-off-by: Heiko Carstens <[email protected]>
Signed-off-by: Alexander Gordeev <[email protected]>
blktests-ci Bot pushed a commit that referenced this pull request Jul 31, 2025
Heiko Carstens says:

===================
A rather large series which is supposed to fix the crash below[1], which was
seen when running the memop kernel kvm selftest.

Problem is that cmpxchg_user_key() is executing code with a non-default
key. If a system is IPL'ed with "LOAD NORMAL", and in addition the previous
system used storage keys where the fetch-protection bit is set for some pages,
and the cmpxchg_user_key() is located within such page a protection exception
will happen when executing such code.

Idea of this series is to register all code locations running with a
non-default key at compile time. All functions, which run with a non-default
key, then must explicitly call an init function which initializes the storage
key of all pages containing such code locations with default key, which
prevents such protection exceptions.

Furthermore all functions containing code which may be executed with a
non-default access key must be marked with __kprobes to prevent out-of-line
execution of any instruction of such functions, which would result in the same
problem.

By default the kernel will not issue any storage key changing instructions
like before, which will preserve the keyless-subset mode optimizations in
hosts.

Other possible implementations which I discarded:

- Moving the code to an own section. This would require an s390 specific
  change to modpost.c, which complains about section mismatches (EX_TABLE
  entries in non-default text section). No other architecture has something
  similar, so let's keep this architecture specific hack local.

- Just apply the default storage key to the whole kprobes text
  section. However this would add special s390 semantics to the kprobes text
  section, which no other architecture has. History has shown that such hacks
  fire back sooner or later.

Furthermore, and to keep this whole stuff quite simple, this only works for
code locations in core kernel code, not within modules. After this series
there is no module code left with such code, and as of now I don't see any new
kernel code which runs with a non-default access key.

Note: the original crash can be reproduced by replacing

page_set_storage_key(real, PAGE_DEFAULT_KEY, 1);

with

page_set_storage_key(real, 8, 1);

in arch/s390/kernel/skey.c:__skey_regions_initialize()

And then run tools/testing/selftests/kvm/s390/memop from the kernel selftests.

[1]:

Unable to handle kernel pointer dereference in virtual kernel address space
Failing address: 0000000000000000 TEID: 000000000000080b
Fault in home space mode while using kernel ASCE.
AS:0000000002528007 R3:00000001ffffc007 S:00000001ffffb801 P:000000000000013d
Oops: 0004 ilc:1 [#1]SMP
Modules linked in:
CPU: 3 UID: 0 PID: 791 Comm: memop Not tainted 6.16.0-rc1-00006-g3b568201d0a6-dirty #11 NONE
Hardware name: IBM 3931 A01 704 (z/VM 7.4.0)
Krnl PSW : 0794f00180000000 000003ffe0f4d91e (__cmpxchg_user_key1+0xbe/0x190)
           R:0 T:1 IO:1 EX:1 Key:9 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
Krnl GPRS: 070003ffdfbf6af0 0000000000070000 0000000095b5a300 0000000000000000
           00000000f1000000 0000000000000000 0000000000000090 0000000000000000
           0000000000000040 0000000000000018 000003ff9b23d000 0000037fe0ef7bd8
           000003ffdfbf7500 00000000962e4000 0000037f00ffffff 0000037fe0ef7aa0
Krnl Code: 000003ffe0f4d912: ad03f0a0            stosm   160(%r15),3
           000003ffe0f4d916: a7780000            lhi     %r7,0
          #000003ffe0f4d91a: b20a6000            spka    0(%r6)
          >000003ffe0f4d91e: b2790100            sacf    256
           000003ffe0f4d922: a56f0080            llill   %r6,128
           000003ffe0f4d926: 5810a000            l       %r1,0(%r10)
           000003ffe0f4d92a: 141e                nr      %r1,%r14
           000003ffe0f4d92c: c0e7ffffffff        xilf    %r14,4294967295
Call Trace:
 [<000003ffe0f4d91e>] __cmpxchg_user_key1+0xbe/0x190
 [<000003ffe0189c6e>] cmpxchg_guest_abs_with_key+0x2fe/0x370
 [<000003ffe016d28e>] kvm_s390_vm_mem_op_cmpxchg+0x17e/0x350
 [<000003ffe0173284>] kvm_arch_vm_ioctl+0x354/0x6f0
 [<000003ffe015fedc>] kvm_vm_ioctl+0x2cc/0x6e0
 [<000003ffe05348ae>] vfs_ioctl+0x2e/0x70
 [<000003ffe0535e70>] __s390x_sys_ioctl+0xe0/0x100
 [<000003ffe0f40f06>] __do_syscall+0x136/0x340
 [<000003ffe0f4cb2e>] system_call+0x6e/0x90
Last Breaking-Event-Address:
 [<000003ffe0f4d896>] __cmpxchg_user_key1+0x36/0x190
===================

Signed-off-by: Alexander Gordeev <[email protected]>
blktests-ci Bot pushed a commit that referenced this pull request Aug 2, 2025
pert script tests fails with segmentation fault as below:

  92: perf script tests:
  --- start ---
  test child forked, pid 103769
  DB test
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.012 MB /tmp/perf-test-script.7rbftEpOzX/perf.data (9 samples) ]
  /usr/libexec/perf-core/tests/shell/script.sh: line 35:
  103780 Segmentation fault      (core dumped)
  perf script -i "${perfdatafile}" -s "${db_test}"
  --- Cleaning up ---
  ---- end(-1) ----
  92: perf script tests                                               : FAILED!

Backtrace pointed to :
	#0  0x0000000010247dd0 in maps.machine ()
	#1  0x00000000101d178c in db_export.sample ()
	#2  0x00000000103412c8 in python_process_event ()
	#3  0x000000001004eb28 in process_sample_event ()
	#4  0x000000001024fcd0 in machines.deliver_event ()
	#5  0x000000001025005c in perf_session.deliver_event ()
	#6  0x00000000102568b0 in __ordered_events__flush.part.0 ()
	#7  0x0000000010251618 in perf_session.process_events ()
	#8  0x0000000010053620 in cmd_script ()
	#9  0x00000000100b5a28 in run_builtin ()
	#10 0x00000000100b5f94 in handle_internal_command ()
	#11 0x0000000010011114 in main ()

Further investigation reveals that this occurs in the `perf script tests`,
because it uses `db_test.py` script. This script sets `perf_db_export_mode = True`.

With `perf_db_export_mode` enabled, if a sample originates from a hypervisor,
perf doesn't set maps for "[H]" sample in the code. Consequently, `al->maps` remains NULL
when `maps__machine(al->maps)` is called from `db_export__sample`.

As al->maps can be NULL in case of Hypervisor samples , use thread->maps
because even for Hypervisor sample, machine should exist.
If we don't have machine for some reason, return -1 to avoid segmentation fault.

Reported-by: Disha Goel <[email protected]>
Signed-off-by: Aditya Bodkhe <[email protected]>
Reviewed-by: Adrian Hunter <[email protected]>
Tested-by: Disha Goel <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Suggested-by: Adrian Hunter <[email protected]>
Signed-off-by: Namhyung Kim <[email protected]>
blktests-ci Bot pushed a commit that referenced this pull request Aug 2, 2025
Without the change `perf `hangs up on charaster devices. On my system
it's enough to run system-wide sampler for a few seconds to get the
hangup:

    $ perf record -a -g --call-graph=dwarf
    $ perf report
    # hung

`strace` shows that hangup happens on reading on a character device
`/dev/dri/renderD128`

    $ strace -y -f -p 2780484
    strace: Process 2780484 attached
    pread64(101</dev/dri/renderD128>, strace: Process 2780484 detached

It's call trace descends into `elfutils`:

    $ gdb -p 2780484
    (gdb) bt
    #0  0x00007f5e508f04b7 in __libc_pread64 (fd=101, buf=0x7fff9df7edb0, count=0, offset=0)
        at ../sysdeps/unix/sysv/linux/pread64.c:25
    #1  0x00007f5e52b79515 in read_file () from /<<NIX>>/elfutils-0.192/lib/libelf.so.1
    #2  0x00007f5e52b25666 in libdw_open_elf () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
    #3  0x00007f5e52b25907 in __libdw_open_file () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
    #4  0x00007f5e52b120a9 in dwfl_report_elf@@ELFUTILS_0.156 ()
       from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
    #5  0x000000000068bf20 in __report_module (al=al@entry=0x7fff9df80010, ip=ip@entry=139803237033216, ui=ui@entry=0x5369b5e0)
        at util/dso.h:537
    #6  0x000000000068c3d1 in report_module (ip=139803237033216, ui=0x5369b5e0) at util/unwind-libdw.c:114
    #7  frame_callback (state=0x535aef10, arg=0x5369b5e0) at util/unwind-libdw.c:242
    #8  0x00007f5e52b261d3 in dwfl_thread_getframes () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
    #9  0x00007f5e52b25bdb in get_one_thread_cb () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
    #10 0x00007f5e52b25faa in dwfl_getthreads () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
    #11 0x00007f5e52b26514 in dwfl_getthread_frames () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
    #12 0x000000000068c6ce in unwind__get_entries (cb=cb@entry=0x5d4620 <unwind_entry>, arg=arg@entry=0x10cd5fa0,
        thread=thread@entry=0x1076a290, data=data@entry=0x7fff9df80540, max_stack=max_stack@entry=127,
        best_effort=best_effort@entry=false) at util/thread.h:152
    #13 0x00000000005dae95 in thread__resolve_callchain_unwind (evsel=0x106006d0, thread=0x1076a290, cursor=0x10cd5fa0,
        sample=0x7fff9df80540, max_stack=127, symbols=true) at util/machine.c:2939
    #14 thread__resolve_callchain_unwind (thread=0x1076a290, cursor=0x10cd5fa0, evsel=0x106006d0, sample=0x7fff9df80540,
        max_stack=127, symbols=true) at util/machine.c:2920
    #15 __thread__resolve_callchain (thread=0x1076a290, cursor=0x10cd5fa0, evsel=0x106006d0, evsel@entry=0x7fff9df80440,
        sample=0x7fff9df80540, parent=parent@entry=0x7fff9df804a0, root_al=root_al@entry=0x7fff9df80440, max_stack=127, symbols=true)
        at util/machine.c:2970
    #16 0x00000000005d0cb2 in thread__resolve_callchain (thread=<optimized out>, cursor=<optimized out>, evsel=0x7fff9df80440,
        sample=<optimized out>, parent=0x7fff9df804a0, root_al=0x7fff9df80440, max_stack=127) at util/machine.h:198
    #17 sample__resolve_callchain (sample=<optimized out>, cursor=<optimized out>, parent=parent@entry=0x7fff9df804a0,
        evsel=evsel@entry=0x106006d0, al=al@entry=0x7fff9df80440, max_stack=max_stack@entry=127) at util/callchain.c:1127
    #18 0x0000000000617e08 in hist_entry_iter__add (iter=iter@entry=0x7fff9df80480, al=al@entry=0x7fff9df80440, max_stack_depth=127,
        arg=arg@entry=0x7fff9df81ae0) at util/hist.c:1255
    #19 0x000000000045d2d0 in process_sample_event (tool=0x7fff9df81ae0, event=<optimized out>, sample=0x7fff9df80540,
        evsel=0x106006d0, machine=<optimized out>) at builtin-report.c:334
    #20 0x00000000005e3bb1 in perf_session__deliver_event (session=0x105ff2c0, event=0x7f5c7d735ca0, tool=0x7fff9df81ae0,
        file_offset=2914716832, file_path=0x105ffbf0 "perf.data") at util/session.c:1367
    #21 0x00000000005e8d93 in do_flush (oe=0x105ffa50, show_progress=false) at util/ordered-events.c:245
    #22 __ordered_events__flush (oe=0x105ffa50, how=OE_FLUSH__ROUND, timestamp=<optimized out>) at util/ordered-events.c:324
    #23 0x00000000005e1f64 in perf_session__process_user_event (session=0x105ff2c0, event=0x7f5c7d752b18, file_offset=2914835224,
        file_path=0x105ffbf0 "perf.data") at util/session.c:1419
    #24 0x00000000005e47c7 in reader__read_event (rd=rd@entry=0x7fff9df81260, session=session@entry=0x105ff2c0,
    --Type <RET> for more, q to quit, c to continue without paging--
    quit
        prog=prog@entry=0x7fff9df81220) at util/session.c:2132
    #25 0x00000000005e4b37 in reader__process_events (rd=0x7fff9df81260, session=0x105ff2c0, prog=0x7fff9df81220)
        at util/session.c:2181
    #26 __perf_session__process_events (session=0x105ff2c0) at util/session.c:2226
    #27 perf_session__process_events (session=session@entry=0x105ff2c0) at util/session.c:2390
    #28 0x0000000000460add in __cmd_report (rep=0x7fff9df81ae0) at builtin-report.c:1076
    #29 cmd_report (argc=<optimized out>, argv=<optimized out>) at builtin-report.c:1827
    #30 0x00000000004c5a40 in run_builtin (p=p@entry=0xd8f7f8 <commands+312>, argc=argc@entry=1, argv=argv@entry=0x7fff9df844b0)
        at perf.c:351
    #31 0x00000000004c5d63 in handle_internal_command (argc=argc@entry=1, argv=argv@entry=0x7fff9df844b0) at perf.c:404
    #32 0x0000000000442de3 in run_argv (argcp=<synthetic pointer>, argv=<synthetic pointer>) at perf.c:448
    #33 main (argc=<optimized out>, argv=0x7fff9df844b0) at perf.c:556

The hangup happens because nothing in` perf` or `elfutils` checks if a
mapped file is easily readable.

The change conservatively skips all non-regular files.

Signed-off-by: Sergei Trofimovich <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Namhyung Kim <[email protected]>
blktests-ci Bot pushed a commit that referenced this pull request Aug 2, 2025
Symbolize stack traces by creating a live machine. Add this
functionality to dump_stack and switch dump_stack users to use
it. Switch TUI to use it. Add stack traces to the child test function
which can be useful to diagnose blocked code.

Example output:
```
$ perf test -vv PERF_RECORD_
...
  7: PERF_RECORD_* events & perf_sample fields:
  7: PERF_RECORD_* events & perf_sample fields                       : Running (1 active)
^C
Signal (2) while running tests.
Terminating tests with the same signal
Internal test harness failure. Completing any started tests:
:  7: PERF_RECORD_* events & perf_sample fields:

---- unexpected signal (2) ----
    #0 0x55788c6210a3 in child_test_sig_handler builtin-test.c:0
    #1 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0
    #2 0x7fc12fe99687 in __internal_syscall_cancel cancellation.c:64
    #3 0x7fc12fee5f7a in clock_nanosleep@GLIBC_2.2.5 clock_nanosleep.c:72
    #4 0x7fc12fef1393 in __nanosleep nanosleep.c:26
    #5 0x7fc12ff02d68 in __sleep sleep.c:55
    #6 0x55788c63196b in test__PERF_RECORD perf-record.c:0
    #7 0x55788c620fb0 in run_test_child builtin-test.c:0
    #8 0x55788c5bd18d in start_command run-command.c:127
    #9 0x55788c621ef3 in __cmd_test builtin-test.c:0
    #10 0x55788c6225bf in cmd_test ??:0
    #11 0x55788c5afbd0 in run_builtin perf.c:0
    #12 0x55788c5afeeb in handle_internal_command perf.c:0
    #13 0x55788c52b383 in main ??:0
    #14 0x7fc12fe33ca8 in __libc_start_call_main libc_start_call_main.h:74
    #15 0x7fc12fe33d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128
    #16 0x55788c52b9d1 in _start ??:0

---- unexpected signal (2) ----
    #0 0x55788c6210a3 in child_test_sig_handler builtin-test.c:0
    #1 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0
    #2 0x7fc12fea3a14 in pthread_sigmask@GLIBC_2.2.5 pthread_sigmask.c:45
    #3 0x7fc12fe49fd9 in __GI___sigprocmask sigprocmask.c:26
    #4 0x7fc12ff2601b in __longjmp_chk longjmp.c:36
    #5 0x55788c6210c0 in print_test_result.isra.0 builtin-test.c:0
    #6 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0
    #7 0x7fc12fe99687 in __internal_syscall_cancel cancellation.c:64
    #8 0x7fc12fee5f7a in clock_nanosleep@GLIBC_2.2.5 clock_nanosleep.c:72
    #9 0x7fc12fef1393 in __nanosleep nanosleep.c:26
    #10 0x7fc12ff02d68 in __sleep sleep.c:55
    #11 0x55788c63196b in test__PERF_RECORD perf-record.c:0
    #12 0x55788c620fb0 in run_test_child builtin-test.c:0
    #13 0x55788c5bd18d in start_command run-command.c:127
    #14 0x55788c621ef3 in __cmd_test builtin-test.c:0
    #15 0x55788c6225bf in cmd_test ??:0
    #16 0x55788c5afbd0 in run_builtin perf.c:0
    #17 0x55788c5afeeb in handle_internal_command perf.c:0
    #18 0x55788c52b383 in main ??:0
    #19 0x7fc12fe33ca8 in __libc_start_call_main libc_start_call_main.h:74
    #20 0x7fc12fe33d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128
    #21 0x55788c52b9d1 in _start ??:0
  7: PERF_RECORD_* events & perf_sample fields                       : Skip (permissions)
```

Signed-off-by: Ian Rogers <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Namhyung Kim <[email protected]>
blktests-ci Bot pushed a commit that referenced this pull request Aug 2, 2025
Calling perf top with branch filters enabled on Intel CPU's
with branch counters logging (A.K.A LBR event logging [1]) support
results in a segfault.

$ perf top  -e '{cpu_core/cpu-cycles/,cpu_core/event=0xc6,umask=0x3,frontend=0x11,name=frontend_retired_dsb_miss/}' -j any,counter
...
Thread 27 "perf" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fffafff76c0 (LWP 949003)]
perf_env__find_br_cntr_info (env=0xf66dc0 <perf_env>, nr=0x0, width=0x7fffafff62c0) at util/env.c:653
653			*width = env->cpu_pmu_caps ? env->br_cntr_width :
(gdb) bt
 #0  perf_env__find_br_cntr_info (env=0xf66dc0 <perf_env>, nr=0x0, width=0x7fffafff62c0) at util/env.c:653
 #1  0x00000000005b1599 in symbol__account_br_cntr (branch=0x7fffcc3db580, evsel=0xfea2d0, offset=12, br_cntr=8) at util/annotate.c:345
 #2  0x00000000005b17fb in symbol__account_cycles (addr=5658172, start=5658160, sym=0x7fffcc0ee420, cycles=539, evsel=0xfea2d0, br_cntr=8) at util/annotate.c:389
 #3  0x00000000005b1976 in addr_map_symbol__account_cycles (ams=0x7fffcd7b01d0, start=0x7fffcd7b02b0, cycles=539, evsel=0xfea2d0, br_cntr=8) at util/annotate.c:422
 #4  0x000000000068d57f in hist__account_cycles (bs=0x110d288, al=0x7fffafff6540, sample=0x7fffafff6760, nonany_branch_mode=false, total_cycles=0x0, evsel=0xfea2d0) at util/hist.c:2850
 #5  0x0000000000446216 in hist_iter__top_callback (iter=0x7fffafff6590, al=0x7fffafff6540, single=true, arg=0x7fffffff9e00) at builtin-top.c:737
 #6  0x0000000000689787 in hist_entry_iter__add (iter=0x7fffafff6590, al=0x7fffafff6540, max_stack_depth=127, arg=0x7fffffff9e00) at util/hist.c:1359
 #7  0x0000000000446710 in perf_event__process_sample (tool=0x7fffffff9e00, event=0x110d250, evsel=0xfea2d0, sample=0x7fffafff6760, machine=0x108c968) at builtin-top.c:845
 #8  0x0000000000447735 in deliver_event (qe=0x7fffffffa120, qevent=0x10fc200) at builtin-top.c:1211
 #9  0x000000000064ccae in do_flush (oe=0x7fffffffa120, show_progress=false) at util/ordered-events.c:245
 #10 0x000000000064d005 in __ordered_events__flush (oe=0x7fffffffa120, how=OE_FLUSH__TOP, timestamp=0) at util/ordered-events.c:324
 #11 0x000000000064d0ef in ordered_events__flush (oe=0x7fffffffa120, how=OE_FLUSH__TOP) at util/ordered-events.c:342
 #12 0x00000000004472a9 in process_thread (arg=0x7fffffff9e00) at builtin-top.c:1120
 #13 0x00007ffff6e7dba8 in start_thread (arg=<optimized out>) at pthread_create.c:448
 #14 0x00007ffff6f01b8c in __GI___clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78

The cause is that perf_env__find_br_cntr_info tries to access a
null pointer pmu_caps in the perf_env struct. A similar issue exists
for homogeneous core systems which use the cpu_pmu_caps structure.

Fix this by populating cpu_pmu_caps and pmu_caps structures with
values from sysfs when calling perf top with branch stack sampling
enabled.

[1], LBR event logging introduced here:
https://lore.kernel.org/all/[email protected]/

Reviewed-by: Ian Rogers <[email protected]>
Signed-off-by: Thomas Falcon <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Namhyung Kim <[email protected]>
blktests-ci Bot pushed a commit that referenced this pull request Aug 4, 2025
Add JIT support for the load_acquire and store_release instructions. The
implementation is similar to the kernel where:

        load_acquire  => plain load -> lwsync
        store_release => lwsync -> plain store

To test the correctness of the implementation, following selftests were
run:

  [fedora@linux-kernel bpf]$ sudo ./test_progs -a \
  verifier_load_acquire,verifier_store_release,atomics
  #11/1    atomics/add:OK
  #11/2    atomics/sub:OK
  #11/3    atomics/and:OK
  #11/4    atomics/or:OK
  #11/5    atomics/xor:OK
  #11/6    atomics/cmpxchg:OK
  #11/7    atomics/xchg:OK
  #11      atomics:OK
  #519/1   verifier_load_acquire/load-acquire, 8-bit:OK
  #519/2   verifier_load_acquire/load-acquire, 8-bit @unpriv:OK
  #519/3   verifier_load_acquire/load-acquire, 16-bit:OK
  #519/4   verifier_load_acquire/load-acquire, 16-bit @unpriv:OK
  #519/5   verifier_load_acquire/load-acquire, 32-bit:OK
  #519/6   verifier_load_acquire/load-acquire, 32-bit @unpriv:OK
  #519/7   verifier_load_acquire/load-acquire, 64-bit:OK
  #519/8   verifier_load_acquire/load-acquire, 64-bit @unpriv:OK
  #519/9   verifier_load_acquire/load-acquire with uninitialized
  src_reg:OK
  #519/10  verifier_load_acquire/load-acquire with uninitialized src_reg
  @unpriv:OK
  #519/11  verifier_load_acquire/load-acquire with non-pointer src_reg:OK
  #519/12  verifier_load_acquire/load-acquire with non-pointer src_reg
  @unpriv:OK
  #519/13  verifier_load_acquire/misaligned load-acquire:OK
  #519/14  verifier_load_acquire/misaligned load-acquire @unpriv:OK
  #519/15  verifier_load_acquire/load-acquire from ctx pointer:OK
  #519/16  verifier_load_acquire/load-acquire from ctx pointer @unpriv:OK
  #519/17  verifier_load_acquire/load-acquire with invalid register R15:OK
  #519/18  verifier_load_acquire/load-acquire with invalid register R15
  @unpriv:OK
  #519/19  verifier_load_acquire/load-acquire from pkt pointer:OK
  #519/20  verifier_load_acquire/load-acquire from flow_keys pointer:OK
  #519/21  verifier_load_acquire/load-acquire from sock pointer:OK
  #519     verifier_load_acquire:OK
  #556/1   verifier_store_release/store-release, 8-bit:OK
  #556/2   verifier_store_release/store-release, 8-bit @unpriv:OK
  #556/3   verifier_store_release/store-release, 16-bit:OK
  #556/4   verifier_store_release/store-release, 16-bit @unpriv:OK
  #556/5   verifier_store_release/store-release, 32-bit:OK
  #556/6   verifier_store_release/store-release, 32-bit @unpriv:OK
  #556/7   verifier_store_release/store-release, 64-bit:OK
  #556/8   verifier_store_release/store-release, 64-bit @unpriv:OK
  #556/9   verifier_store_release/store-release with uninitialized
  src_reg:OK
  #556/10  verifier_store_release/store-release with uninitialized src_reg
  @unpriv:OK
  #556/11  verifier_store_release/store-release with uninitialized
  dst_reg:OK
  #556/12  verifier_store_release/store-release with uninitialized dst_reg
  @unpriv:OK
  #556/13  verifier_store_release/store-release with non-pointer
  dst_reg:OK
  #556/14  verifier_store_release/store-release with non-pointer dst_reg
  @unpriv:OK
  #556/15  verifier_store_release/misaligned store-release:OK
  #556/16  verifier_store_release/misaligned store-release @unpriv:OK
  #556/17  verifier_store_release/store-release to ctx pointer:OK
  #556/18  verifier_store_release/store-release to ctx pointer @unpriv:OK
  #556/19  verifier_store_release/store-release, leak pointer to stack:OK
  #556/20  verifier_store_release/store-release, leak pointer to stack
  @unpriv:OK
  #556/21  verifier_store_release/store-release, leak pointer to map:OK
  #556/22  verifier_store_release/store-release, leak pointer to map
  @unpriv:OK
  #556/23  verifier_store_release/store-release with invalid register
  R15:OK
  #556/24  verifier_store_release/store-release with invalid register R15
  @unpriv:OK
  #556/25  verifier_store_release/store-release to pkt pointer:OK
  #556/26  verifier_store_release/store-release to flow_keys pointer:OK
  #556/27  verifier_store_release/store-release to sock pointer:OK
  #556     verifier_store_release:OK
  Summary: 3/55 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Puranjay Mohan <[email protected]>
Tested-by: Saket Kumar Bhaskar <[email protected]>
Reviewed-by: Hari Bathini <[email protected]>
Signed-off-by: Madhavan Srinivasan <[email protected]>
Link: https://patch.msgid.link/[email protected]
blktests-ci Bot pushed a commit that referenced this pull request Oct 9, 2025
The test starts a workload and then opens events. If the events fail
to open, for example because of perf_event_paranoid, the gopipe of the
workload is leaked and the file descriptor leak check fails when the
test exits. To avoid this cancel the workload when opening the events
fails.

Before:
```
$ perf test -vv 7
  7: PERF_RECORD_* events & perf_sample fields:
 --- start ---
test child forked, pid 1189568
Using CPUID GenuineIntel-6-B7-1
 ------------------------------------------------------------
perf_event_attr:
  type                    	   0 (PERF_TYPE_HARDWARE)
  config                  	   0xa00000000 (cpu_atom/PERF_COUNT_HW_CPU_CYCLES/)
  disabled                	   1
 ------------------------------------------------------------
sys_perf_event_open: pid 0  cpu -1  group_fd -1  flags 0x8
sys_perf_event_open failed, error -13
 ------------------------------------------------------------
perf_event_attr:
  type                             0 (PERF_TYPE_HARDWARE)
  config                           0xa00000000 (cpu_atom/PERF_COUNT_HW_CPU_CYCLES/)
  disabled                         1
  exclude_kernel                   1
 ------------------------------------------------------------
sys_perf_event_open: pid 0  cpu -1  group_fd -1  flags 0x8 = 3
 ------------------------------------------------------------
perf_event_attr:
  type                             0 (PERF_TYPE_HARDWARE)
  config                           0x400000000 (cpu_core/PERF_COUNT_HW_CPU_CYCLES/)
  disabled                         1
 ------------------------------------------------------------
sys_perf_event_open: pid 0  cpu -1  group_fd -1  flags 0x8
sys_perf_event_open failed, error -13
 ------------------------------------------------------------
perf_event_attr:
  type                             0 (PERF_TYPE_HARDWARE)
  config                           0x400000000 (cpu_core/PERF_COUNT_HW_CPU_CYCLES/)
  disabled                         1
  exclude_kernel                   1
 ------------------------------------------------------------
sys_perf_event_open: pid 0  cpu -1  group_fd -1  flags 0x8 = 3
Attempt to add: software/cpu-clock/
..after resolving event: software/config=0/
cpu-clock -> software/cpu-clock/
 ------------------------------------------------------------
perf_event_attr:
  type                             1 (PERF_TYPE_SOFTWARE)
  size                             136
  config                           0x9 (PERF_COUNT_SW_DUMMY)
  sample_type                      IP|TID|TIME|CPU
  read_format                      ID|LOST
  disabled                         1
  inherit                          1
  mmap                             1
  comm                             1
  enable_on_exec                   1
  task                             1
  sample_id_all                    1
  mmap2                            1
  comm_exec                        1
  ksymbol                          1
  bpf_event                        1
  { wakeup_events, wakeup_watermark } 1
 ------------------------------------------------------------
sys_perf_event_open: pid 1189569  cpu 0  group_fd -1  flags 0x8
sys_perf_event_open failed, error -13
perf_evlist__open: Permission denied
 ---- end(-2) ----
Leak of file descriptor 6 that opened: 'pipe:[14200347]'
 ---- unexpected signal (6) ----
iFailed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
    #0 0x565358f6666e in child_test_sig_handler builtin-test.c:311
    #1 0x7f29ce849df0 in __restore_rt libc_sigaction.c:0
    #2 0x7f29ce89e95c in __pthread_kill_implementation pthread_kill.c:44
    #3 0x7f29ce849cc2 in raise raise.c:27
    #4 0x7f29ce8324ac in abort abort.c:81
    #5 0x565358f662d4 in check_leaks builtin-test.c:226
    #6 0x565358f6682e in run_test_child builtin-test.c:344
    #7 0x565358ef7121 in start_command run-command.c:128
    #8 0x565358f67273 in start_test builtin-test.c:545
    #9 0x565358f6771d in __cmd_test builtin-test.c:647
    #10 0x565358f682bd in cmd_test builtin-test.c:849
    #11 0x565358ee5ded in run_builtin perf.c:349
    #12 0x565358ee6085 in handle_internal_command perf.c:401
    #13 0x565358ee61de in run_argv perf.c:448
    #14 0x565358ee6527 in main perf.c:555
    #15 0x7f29ce833ca8 in __libc_start_call_main libc_start_call_main.h:74
    #16 0x7f29ce833d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128
    #17 0x565358e391c1 in _start perf[851c1]
  7: PERF_RECORD_* events & perf_sample fields                       : FAILED!
```

After:
```
$ perf test 7
  7: PERF_RECORD_* events & perf_sample fields                       : Skip (permissions)
```

Fixes: 16d00fe ("perf tests: Move test__PERF_RECORD into separate object")
Signed-off-by: Ian Rogers <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Athira Rajeev <[email protected]>
Cc: Chun-Tse Shao <[email protected]>
Cc: Howard Chu <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
blktests-ci Bot pushed a commit that referenced this pull request Nov 3, 2025
Commit 4e65bda ("ASoC: wcd934x: fix error handling in
wcd934x_codec_parse_data()") revealed the problem in the slimbus regmap.
That commit breaks audio playback, for instance, on sdm845 Thundercomm
Dragonboard 845c board:

 Unable to handle kernel paging request at virtual address ffff8000847cbad4
 ...
 CPU: 5 UID: 0 PID: 776 Comm: aplay Not tainted 6.18.0-rc1-00028-g7ea30958b305 #11 PREEMPT
 Hardware name: Thundercomm Dragonboard 845c (DT)
 ...
 Call trace:
  slim_xfer_msg+0x24/0x1ac [slimbus] (P)
  slim_read+0x48/0x74 [slimbus]
  regmap_slimbus_read+0x18/0x24 [regmap_slimbus]
  _regmap_raw_read+0xe8/0x174
  _regmap_bus_read+0x44/0x80
  _regmap_read+0x60/0xd8
  _regmap_update_bits+0xf4/0x140
  _regmap_select_page+0xa8/0x124
  _regmap_raw_write_impl+0x3b8/0x65c
  _regmap_bus_raw_write+0x60/0x80
  _regmap_write+0x58/0xc0
  regmap_write+0x4c/0x80
  wcd934x_hw_params+0x494/0x8b8 [snd_soc_wcd934x]
  snd_soc_dai_hw_params+0x3c/0x7c [snd_soc_core]
  __soc_pcm_hw_params+0x22c/0x634 [snd_soc_core]
  dpcm_be_dai_hw_params+0x1d4/0x38c [snd_soc_core]
  dpcm_fe_dai_hw_params+0x9c/0x17c [snd_soc_core]
  snd_pcm_hw_params+0x124/0x464 [snd_pcm]
  snd_pcm_common_ioctl+0x110c/0x1820 [snd_pcm]
  snd_pcm_ioctl+0x34/0x4c [snd_pcm]
  __arm64_sys_ioctl+0xac/0x104
  invoke_syscall+0x48/0x104
  el0_svc_common.constprop.0+0x40/0xe0
  do_el0_svc+0x1c/0x28
  el0_svc+0x34/0xec
  el0t_64_sync_handler+0xa0/0xf0
  el0t_64_sync+0x198/0x19c

The __devm_regmap_init_slimbus() started to be used instead of
__regmap_init_slimbus() after the commit mentioned above and turns out
the incorrect bus_context pointer (3rd argument) was used in
__devm_regmap_init_slimbus(). It should be just "slimbus" (which is equal
to &slimbus->dev). Correct it. The wcd934x codec seems to be the only or
the first user of devm_regmap_init_slimbus() but we should fix it till
the point where __devm_regmap_init_slimbus() was introduced therefore
two "Fixes" tags.

While at this, also correct the same argument in __regmap_init_slimbus().

Fixes: 4e65bda ("ASoC: wcd934x: fix error handling in wcd934x_codec_parse_data()")
Fixes: 7d6f7fb ("regmap: add SLIMbus support")
Cc: [email protected]
Cc: Dmitry Baryshkov <[email protected]>
Cc: Ma Ke <[email protected]>
Cc: Steev Klimaszewski <[email protected]>
Cc: Srinivas Kandagatla <[email protected]>
Reviewed-by: Abel Vesa <[email protected]>
Signed-off-by: Alexey Klimov <[email protected]>
Reviewed-by: Dmitry Baryshkov <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Mark Brown <[email protected]>
blktests-ci Bot pushed a commit that referenced this pull request Feb 3, 2026
An UAF issue was observed:

BUG: KASAN: slab-use-after-free in page_counter_uncharge+0x65/0x150
Write of size 8 at addr ffff888106715440 by task insmod/527

CPU: 4 UID: 0 PID: 527 Comm: insmod    6.19.0-rc7-next-20260129+ #11
Tainted: [O]=OOT_MODULE
Call Trace:
<TASK>
dump_stack_lvl+0x82/0xd0
kasan_report+0xca/0x100
kasan_check_range+0x39/0x1c0
page_counter_uncharge+0x65/0x150
dmem_cgroup_uncharge+0x1f/0x260

Allocated by task 527:

Freed by task 0:

The buggy address belongs to the object at ffff888106715400
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 64 bytes inside of
freed 512-byte region [ffff888106715400, ffff888106715600)

The buggy address belongs to the physical page:

Memory state around the buggy address:
ffff888106715300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888106715380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888106715400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
				     ^
ffff888106715480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888106715500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

The issue occurs because a pool can still be held by a caller after its
associated memory region is unregistered. The current implementation frees
the pool even if users still hold references to it (e.g., before uncharge
operations complete).

This patch adds a reference counter to each pool, ensuring that a pool is
only freed when its reference count drops to zero.

Fixes: b168ed4 ("kernel/cgroup: Add "dmem" memory accounting cgroup")
Cc: [email protected] # v6.14+
Signed-off-by: Chen Ridong <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>
blktests-ci Bot pushed a commit that referenced this pull request Feb 22, 2026
The ETM decoder incorrectly assumed that auxtrace queue indices were
equivalent to CPU number. This assumption is used for inserting records
into the queue, and for fetching queues when given a CPU number. This
assumption held when Perf always opened a dummy event on every CPU, even
if the user provided a subset of CPUs on the commandline, resulting in
the indices aligning.

For example:

  # event : name = cs_etm//u, , id = { 2451, 2452 }, type = 11 (cs_etm), size = 136, config = 0x4010, { sample_period, samp>
  # event : name = dummy:u, , id = { 2453, 2454, 2455, 2456 }, type = 1 (PERF_TYPE_SOFTWARE), size = 136, config = 0x9 (PER>

  0 0 0x200 [0xd0]: PERF_RECORD_ID_INDEX nr: 6
  ... id: 2451  idx: 2  cpu: 2  tid: -1
  ... id: 2452  idx: 3  cpu: 3  tid: -1
  ... id: 2453  idx: 0  cpu: 0  tid: -1
  ... id: 2454  idx: 1  cpu: 1  tid: -1
  ... id: 2455  idx: 2  cpu: 2  tid: -1
  ... id: 2456  idx: 3  cpu: 3  tid: -1

Since commit 811082e ("perf parse-events: Support user CPUs mixed
with threads/processes") the dummy event no longer behaves in this way,
making the ETM event indices start from 0 on the first CPU recorded
regardless of its ID:

  # event : name = cs_etm//u, , id = { 771, 772 }, type = 11 (cs_etm), size = 144, config = 0x4010, { sample_period, sample>
  # event : name = dummy:u, , id = { 773, 774 }, type = 1 (PERF_TYPE_SOFTWARE), size = 144, config = 0x9 (PERF_COUNT_SW_DUM>

  0 0 0x200 [0x90]: PERF_RECORD_ID_INDEX nr: 4
  ... id: 771  idx: 0  cpu: 2  tid: -1
  ... id: 772  idx: 1  cpu: 3  tid: -1
  ... id: 773  idx: 0  cpu: 2  tid: -1
  ... id: 774  idx: 1  cpu: 3  tid: -1

This causes the following segfault when decoding:

  $ perf record -e cs_etm//u -C 2,3 -- true
  $ perf report

  perf: Segmentation fault
  -------- backtrace --------
  #0 0xaaaabf9fd020 in ui__signal_backtrace setup.c:110
  #1 0xffffab5c7930 in __kernel_rt_sigreturn [vdso][930]
  #2 0xaaaabfb68d30 in cs_etm_decoder__reset cs-etm-decoder.c:85
  #3 0xaaaabfb65930 in cs_etm__get_data_block cs-etm.c:2032
  #4 0xaaaabfb666fc in cs_etm__run_per_cpu_timeless_decoder cs-etm.c:2551
  #5 0xaaaabfb6692c in (cs_etm__process_timeless_queues cs-etm.c:2612
  #6 0xaaaabfb63390 in cs_etm__flush_events cs-etm.c:921
  #7 0xaaaabfb324c0 in auxtrace__flush_events auxtrace.c:2915
  #8 0xaaaabfaac378 in __perf_session__process_events session.c:2285
  #9 0xaaaabfaacc9c in perf_session__process_events session.c:2442
  #10 0xaaaabf8d3d90 in __cmd_report builtin-report.c:1085
  #11 0xaaaabf8d6944 in cmd_report builtin-report.c:1866
  #12 0xaaaabf95ebfc in run_builtin perf.c:351
  #13 0xaaaabf95eeb0 in handle_internal_command perf.c:404
  #14 0xaaaabf95f068 in run_argv perf.c:451
  #15 0xaaaabf95f390 in main perf.c:558
  #16 0xffffaab97400 in __libc_start_call_main libc_start_call_main.h:74
  #17 0xffffaab974d8 in __libc_start_main@@GLIBC_2.34 libc-start.c:128
  #18 0xaaaabf8aa8f0 in _start perf[7a8f0]

Fix it by inserting into the queues based on CPU number, rather than
using the index.

Fixes: 811082e ("perf parse-events: Support user CPUs mixed with threads/processes")
Signed-off-by: James Clark <[email protected]>
Tested-by: Leo Yan <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: [email protected]
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: John Garry <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Mike Leach <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Suzuki Poulouse <[email protected]>
Cc: Thomas Falcon <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
blktests-ci Bot pushed a commit that referenced this pull request Mar 2, 2026
Ihor Solodrai says:

====================
selftests/bpf: Fixes for userspace ASAN

This series includes various fixes aiming to enable test_progs run
with userspace address sanitizer on BPF CI.

The first five patches add a simplified implementation of strscpy() to
selftests/bpf and then replace strcpy/strncpy usages across the tests
with it. See relevant discussions [1][2].

Patch #6 fixes the selftests/bpf/test_progs build with:

    SAN_CFLAGS="-fsanitize=address -fno-omit-frame-pointer"

The subsequent patches fix bugs reported by the address sanitizer on
attempt to run the tests.

[1] https://lore.kernel.org/bpf/CAADnVQ+9uw2_o388j43EWiAPdMB=3FLx2jq-9zRSvqrv-wgRag@mail.gmail.com/
[2] https://lore.kernel.org/bpf/[email protected]/
---

v3->v4:
  - combine strscpy and ASAN series into one (Alexei)
  - make the count arg of strscpy() optional via macro and fixup
    relevant call sites (Alexei)
  - remove strscpy_cat() from this series (Alexei)

v3: https://lore.kernel.org/bpf/[email protected]/

v2->v3:
  - rebase on top of "selftests/bpf: Add and use strscpy()"
    - https://lore.kernel.org/bpf/[email protected]/
  - uprobe_multi_test.c: memset static struct child at the beginning
    of a test *and* zero out child->thread in release_child (patch #9,
    Mykyta)
  - nits in test_sysctl.c (patch #11, Eduard)
  - bpftool_helpers.c: update to use strscpy (patch #14, Alexei)
  - add __asan_on_error handler to still dump test logs even with ASAN
    build (patch #15, Mykyta)

v2: https://lore.kernel.org/bpf/[email protected]/

v1->v2:
  - rebase on bpf (v1 was targeting bpf-next)
  - add ASAN flag handling in selftests/bpf/Makefile (Eduard)
  - don't override SIGSEGV handler in test_progs with ASAN (Eduard)
  - add error messages in detect_bpftool_path (Mykyta)
  - various nits (Eduard, Jiri, Mykyta, Alexis)

v1: https://lore.kernel.org/bpf/[email protected]/
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
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