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@recursivetree recursivetree commented Jan 4, 2025

Commit 1

The port to 6.9-rc1 on the ev3dev-bookworm branch contains a regression that causes the SD card driver to fail. This PR backports the fix.

With this fix and a few changes to get the lego-drivers to compile, I can boot into brickman, although I haven't (yet) tested whether motors and sensors work.

The fix:
https://lore.kernel.org/all/20240711081838.47256-1-bastien.curutchet@bootlin.com/
https://lore.kernel.org/all/20240711081838.47256-2-bastien.curutchet@bootlin.com/

The regression:
https://lore.kernel.org/all/20240127-mmc-proper-kmap-v2-1-d8e732aa97d1@linaro.org/

Commit 2

The next commit is taken from the buster branch. (https://github.com/ev3dev/ev3-kernel/commits/ev3dev-buster/?before=ad1f6c8727bce29ec400c9385f7f72ee2c0e59fc+35) It is required to build the lego-linux-drivers: https://github.com/ev3dev/lego-linux-drivers/blob/1b387f3bacb4ab8f623494d29a855de6163c8dec/ev3/ev3_pru.c#L232

bastien-curutchet and others added 2 commits January 4, 2025 22:29
…length

No check is done on the size of the data to be transmiited. This causes
a kernel panic when this size exceeds the sg_miter's length.

Limit the number of transmitted bytes to sgm->length.

Cc: stable@vger.kernel.org
Fixes: ed01d21 ("mmc: davinci_mmc: Use sg_miter for PIO")
Signed-off-by: Bastien Curutchet <bastien.curutchet@bootlin.com>
Link: https://lore.kernel.org/r/20240711081838.47256-2-bastien.curutchet@bootlin.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This adds a new type for frequency to the IIO channel type enumeration.

Units are in Hz.

Signed-off-by: David Lechner <david@lechnology.com>
@recursivetree recursivetree changed the title bookworm/linux 6.9: backport SD card fix bookworm/linux 6.9: Some progress Jan 7, 2025
Project516 pushed a commit to Project516/ev3-kernel that referenced this pull request Aug 14, 2025
…void Priority Inversion in SRIOV

commit dc0297f3198bd60108ccbd167ee5d9fa4af31ed0 upstream.

RLCG Register Access is a way for virtual functions to safely access GPU
registers in a virtualized environment., including TLB flushes and
register reads. When multiple threads or VFs try to access the same
registers simultaneously, it can lead to race conditions. By using the
RLCG interface, the driver can serialize access to the registers. This
means that only one thread can access the registers at a time,
preventing conflicts and ensuring that operations are performed
correctly. Additionally, when a low-priority task holds a mutex that a
high-priority task needs, ie., If a thread holding a spinlock tries to
acquire a mutex, it can lead to priority inversion. register access in
amdgpu_virt_rlcg_reg_rw especially in a fast code path is critical.

The call stack shows that the function amdgpu_virt_rlcg_reg_rw is being
called, which attempts to acquire the mutex. This function is invoked
from amdgpu_sriov_wreg, which in turn is called from
gmc_v11_0_flush_gpu_tlb.

The [ BUG: Invalid wait context ] indicates that a thread is trying to
acquire a mutex while it is in a context that does not allow it to sleep
(like holding a spinlock).

Fixes the below:

[  253.013423] =============================
[  253.013434] [ BUG: Invalid wait context ]
[  253.013446] 6.12.0-amdstaging-drm-next-lol-050225 ev3dev#14 Tainted: G     U     OE
[  253.013464] -----------------------------
[  253.013475] kworker/0:1/10 is trying to lock:
[  253.013487] ffff9f30542e3cf8 (&adev->virt.rlcg_reg_lock){+.+.}-{3:3}, at: amdgpu_virt_rlcg_reg_rw+0xf6/0x330 [amdgpu]
[  253.013815] other info that might help us debug this:
[  253.013827] context-{4:4}
[  253.013835] 3 locks held by kworker/0:1/10:
[  253.013847]  #0: ffff9f3040050f58 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x3f5/0x680
[  253.013877]  #1: ffffb789c008be40 ((work_completion)(&wfc.work)){+.+.}-{0:0}, at: process_one_work+0x1d6/0x680
[  253.013905]  #2: ffff9f3054281838 (&adev->gmc.invalidate_lock){+.+.}-{2:2}, at: gmc_v11_0_flush_gpu_tlb+0x198/0x4f0 [amdgpu]
[  253.014154] stack backtrace:
[  253.014164] CPU: 0 UID: 0 PID: 10 Comm: kworker/0:1 Tainted: G     U     OE      6.12.0-amdstaging-drm-next-lol-050225 ev3dev#14
[  253.014189] Tainted: [U]=USER, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
[  253.014203] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 11/18/2024
[  253.014224] Workqueue: events work_for_cpu_fn
[  253.014241] Call Trace:
[  253.014250]  <TASK>
[  253.014260]  dump_stack_lvl+0x9b/0xf0
[  253.014275]  dump_stack+0x10/0x20
[  253.014287]  __lock_acquire+0xa47/0x2810
[  253.014303]  ? srso_alias_return_thunk+0x5/0xfbef5
[  253.014321]  lock_acquire+0xd1/0x300
[  253.014333]  ? amdgpu_virt_rlcg_reg_rw+0xf6/0x330 [amdgpu]
[  253.014562]  ? __lock_acquire+0xa6b/0x2810
[  253.014578]  __mutex_lock+0x85/0xe20
[  253.014591]  ? amdgpu_virt_rlcg_reg_rw+0xf6/0x330 [amdgpu]
[  253.014782]  ? sched_clock_noinstr+0x9/0x10
[  253.014795]  ? srso_alias_return_thunk+0x5/0xfbef5
[  253.014808]  ? local_clock_noinstr+0xe/0xc0
[  253.014822]  ? amdgpu_virt_rlcg_reg_rw+0xf6/0x330 [amdgpu]
[  253.015012]  ? srso_alias_return_thunk+0x5/0xfbef5
[  253.015029]  mutex_lock_nested+0x1b/0x30
[  253.015044]  ? mutex_lock_nested+0x1b/0x30
[  253.015057]  amdgpu_virt_rlcg_reg_rw+0xf6/0x330 [amdgpu]
[  253.015249]  amdgpu_sriov_wreg+0xc5/0xd0 [amdgpu]
[  253.015435]  gmc_v11_0_flush_gpu_tlb+0x44b/0x4f0 [amdgpu]
[  253.015667]  gfx_v11_0_hw_init+0x499/0x29c0 [amdgpu]
[  253.015901]  ? __pfx_smu_v13_0_update_pcie_parameters+0x10/0x10 [amdgpu]
[  253.016159]  ? srso_alias_return_thunk+0x5/0xfbef5
[  253.016173]  ? smu_hw_init+0x18d/0x300 [amdgpu]
[  253.016403]  amdgpu_device_init+0x29ad/0x36a0 [amdgpu]
[  253.016614]  amdgpu_driver_load_kms+0x1a/0xc0 [amdgpu]
[  253.017057]  amdgpu_pci_probe+0x1c2/0x660 [amdgpu]
[  253.017493]  local_pci_probe+0x4b/0xb0
[  253.017746]  work_for_cpu_fn+0x1a/0x30
[  253.017995]  process_one_work+0x21e/0x680
[  253.018248]  worker_thread+0x190/0x330
[  253.018500]  ? __pfx_worker_thread+0x10/0x10
[  253.018746]  kthread+0xe7/0x120
[  253.018988]  ? __pfx_kthread+0x10/0x10
[  253.019231]  ret_from_fork+0x3c/0x60
[  253.019468]  ? __pfx_kthread+0x10/0x10
[  253.019701]  ret_from_fork_asm+0x1a/0x30
[  253.019939]  </TASK>

v2: s/spin_trylock/spin_lock_irqsave to be safe (Christian).

Fixes: e864180 ("drm/amdgpu: Add lock around VF RLCG interface")
Cc: lin cao <lin.cao@amd.com>
Cc: Jingwen Chen <Jingwen.Chen2@amd.com>
Cc: Victor Skvortsov <victor.skvortsov@amd.com>
Cc: Zhigang Luo <zhigang.luo@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Suggested-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[ Minor context change fixed. ]
Signed-off-by: Wenshan Lan <jetlan9@163.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Project516 pushed a commit to Project516/ev3-kernel that referenced this pull request Aug 14, 2025
[ Upstream commit fa787ac07b3ceb56dd88a62d1866038498e96230 ]

In KVM guests with Hyper-V hypercalls enabled, the hypercalls
HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST and HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX
allow a guest to request invalidation of portions of a virtual TLB.
For this, the hypercall parameter includes a list of GVAs that are supposed
to be invalidated.

However, when non-canonical GVAs are passed, there is currently no
filtering in place and they are eventually passed to checked invocations of
INVVPID on Intel / INVLPGA on AMD.  While AMD's INVLPGA silently ignores
non-canonical addresses (effectively a no-op), Intel's INVVPID explicitly
signals VM-Fail and ultimately triggers the WARN_ONCE in invvpid_error():

  invvpid failed: ext=0x0 vpid=1 gva=0xaaaaaaaaaaaaa000
  WARNING: CPU: 6 PID: 326 at arch/x86/kvm/vmx/vmx.c:482
  invvpid_error+0x91/0xa0 [kvm_intel]
  Modules linked in: kvm_intel kvm 9pnet_virtio irqbypass fuse
  CPU: 6 UID: 0 PID: 326 Comm: kvm-vm Not tainted 6.15.0 ev3dev#14 PREEMPT(voluntary)
  RIP: 0010:invvpid_error+0x91/0xa0 [kvm_intel]
  Call Trace:
    vmx_flush_tlb_gva+0x320/0x490 [kvm_intel]
    kvm_hv_vcpu_flush_tlb+0x24f/0x4f0 [kvm]
    kvm_arch_vcpu_ioctl_run+0x3013/0x5810 [kvm]

Hyper-V documents that invalid GVAs (those that are beyond a partition's
GVA space) are to be ignored.  While not completely clear whether this
ruling also applies to non-canonical GVAs, it is likely fine to make that
assumption, and manual testing on Azure confirms "real" Hyper-V interprets
the specification in the same way.

Skip non-canonical GVAs when processing the list of address to avoid
tripping the INVVPID failure.  Alternatively, KVM could filter out "bad"
GVAs before inserting into the FIFO, but practically speaking the only
downside of pushing validation to the final processing is that doing so
is suboptimal for the guest, and no well-behaved guest will request TLB
flushes for non-canonical addresses.

Fixes: 2609708 ("KVM: x86: hyper-v: Handle HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST{,EX} calls gently")
Cc: stable@vger.kernel.org
Signed-off-by: Manuel Andreas <manuel.andreas@tum.de>
Suggested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/c090efb3-ef82-499f-a5e0-360fc8420fb7@tum.de
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Will this be merged into the bookworm branch?

Project516 pushed a commit to Project516/ev3-kernel that referenced this pull request Dec 12, 2025
[ Upstream commit 48918cacefd226af44373e914e63304927c0e7dc ]

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
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    #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
    ev3dev#6 0x565358f6682e in run_test_child builtin-test.c:344
    ev3dev#7 0x565358ef7121 in start_command run-command.c:128
    ev3dev#8 0x565358f67273 in start_test builtin-test.c:545
    ev3dev#9 0x565358f6771d in __cmd_test builtin-test.c:647
    ev3dev#10 0x565358f682bd in cmd_test builtin-test.c:849
    ev3dev#11 0x565358ee5ded in run_builtin perf.c:349
    ev3dev#12 0x565358ee6085 in handle_internal_command perf.c:401
    ev3dev#13 0x565358ee61de in run_argv perf.c:448
    ev3dev#14 0x565358ee6527 in main perf.c:555
    ev3dev#15 0x7f29ce833ca8 in __libc_start_call_main libc_start_call_main.h:74
    ev3dev#16 0x7f29ce833d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128
    ev3dev#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 <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.ibm.com>
Cc: Chun-Tse Shao <ctshao@google.com>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Project516 pushed a commit to Project516/ev3-kernel that referenced this pull request Dec 12, 2025
[ Upstream commit 738d5a51864ed8d7a68600b8c0c63fe6fe5c4f20 ]

hfsplus_bmap_alloc can trigger a crash if a
record offset or length is larger than node_size

[   15.264282] BUG: KASAN: slab-out-of-bounds in hfsplus_bmap_alloc+0x887/0x8b0
[   15.265192] Read of size 8 at addr ffff8881085ca188 by task test/183
[   15.265949]
[   15.266163] CPU: 0 UID: 0 PID: 183 Comm: test Not tainted 6.17.0-rc2-gc17b750b3ad9 ev3dev#14 PREEMPT(voluntary)
[   15.266165] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[   15.266167] Call Trace:
[   15.266168]  <TASK>
[   15.266169]  dump_stack_lvl+0x53/0x70
[   15.266173]  print_report+0xd0/0x660
[   15.266181]  kasan_report+0xce/0x100
[   15.266185]  hfsplus_bmap_alloc+0x887/0x8b0
[   15.266208]  hfs_btree_inc_height.isra.0+0xd5/0x7c0
[   15.266217]  hfsplus_brec_insert+0x870/0xb00
[   15.266222]  __hfsplus_ext_write_extent+0x428/0x570
[   15.266225]  __hfsplus_ext_cache_extent+0x5e/0x910
[   15.266227]  hfsplus_ext_read_extent+0x1b2/0x200
[   15.266233]  hfsplus_file_extend+0x5a7/0x1000
[   15.266237]  hfsplus_get_block+0x12b/0x8c0
[   15.266238]  __block_write_begin_int+0x36b/0x12c0
[   15.266251]  block_write_begin+0x77/0x110
[   15.266252]  cont_write_begin+0x428/0x720
[   15.266259]  hfsplus_write_begin+0x51/0x100
[   15.266262]  cont_write_begin+0x272/0x720
[   15.266270]  hfsplus_write_begin+0x51/0x100
[   15.266274]  generic_perform_write+0x321/0x750
[   15.266285]  generic_file_write_iter+0xc3/0x310
[   15.266289]  __kernel_write_iter+0x2fd/0x800
[   15.266296]  dump_user_range+0x2ea/0x910
[   15.266301]  elf_core_dump+0x2a94/0x2ed0
[   15.266320]  vfs_coredump+0x1d85/0x45e0
[   15.266349]  get_signal+0x12e3/0x1990
[   15.266357]  arch_do_signal_or_restart+0x89/0x580
[   15.266362]  irqentry_exit_to_user_mode+0xab/0x110
[   15.266364]  asm_exc_page_fault+0x26/0x30
[   15.266366] RIP: 0033:0x41bd35
[   15.266367] Code: bc d1 f3 0f 7f 27 f3 0f 7f 6f 10 f3 0f 7f 77 20 f3 0f 7f 7f 30 49 83 c0 0f 49 29 d0 48 8d 7c 17 31 e9 9f 0b 00 00 66 0f ef c0 <f3> 0f 6f 0e f3 0f 6f 56 10 66 0f 74 c1 66 0f d7 d0 49 83 f8f
[   15.266369] RSP: 002b:00007ffc9e62d078 EFLAGS: 00010283
[   15.266371] RAX: 00007ffc9e62d100 RBX: 0000000000000000 RCX: 0000000000000000
[   15.266372] RDX: 00000000000000e0 RSI: 0000000000000000 RDI: 00007ffc9e62d100
[   15.266373] RBP: 0000400000000040 R08: 00000000000000e0 R09: 0000000000000000
[   15.266374] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
[   15.266375] R13: 0000000000000000 R14: 0000000000000000 R15: 0000400000000000
[   15.266376]  </TASK>

When calling hfsplus_bmap_alloc to allocate a free node, this function
first retrieves the bitmap from header node and map node using node->page
together with the offset and length from hfs_brec_lenoff

```
len = hfs_brec_lenoff(node, 2, &off16);
off = off16;

off += node->page_offset;
pagep = node->page + (off >> PAGE_SHIFT);
data = kmap_local_page(*pagep);
```

However, if the retrieved offset or length is invalid(i.e. exceeds
node_size), the code may end up accessing pages outside the allocated
range for this node.

This patch adds proper validation of both offset and length before use,
preventing out-of-bounds page access. Move is_bnode_offset_valid and
check_and_correct_requested_length to hfsplus_fs.h, as they may be
required by other functions.

Reported-by: syzbot+356aed408415a56543cd@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/67bcb4a6.050a0220.bbfd1.008f.GAE@google.com/
Signed-off-by: Yang Chenzhi <yang.chenzhi@vivo.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
Link: https://lore.kernel.org/r/20250818141734.8559-2-yang.chenzhi@vivo.com
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Project516 pushed a commit to Project516/ev3-kernel that referenced this pull request Dec 18, 2025
[ Upstream commit 163e5f2b96632b7fb2eaa965562aca0dbdf9f996 ]

When using perf record with the `--overwrite` option, a segmentation fault
occurs if an event fails to open. For example:

  perf record -e cycles-ct -F 1000 -a --overwrite
  Error:
  cycles-ct:H: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat'
  perf: Segmentation fault
      #0 0x6466b6 in dump_stack debug.c:366
      #1 0x646729 in sighandler_dump_stack debug.c:378
      #2 0x453fd1 in sigsegv_handler builtin-record.c:722
      #3 0x7f8454e65090 in __restore_rt libc-2.32.so[54090]
      #4 0x6c5671 in __perf_event__synthesize_id_index synthetic-events.c:1862
      #5 0x6c5ac0 in perf_event__synthesize_id_index synthetic-events.c:1943
      ev3dev#6 0x458090 in record__synthesize builtin-record.c:2075
      ev3dev#7 0x45a85a in __cmd_record builtin-record.c:2888
      ev3dev#8 0x45deb6 in cmd_record builtin-record.c:4374
      ev3dev#9 0x4e5e33 in run_builtin perf.c:349
      ev3dev#10 0x4e60bf in handle_internal_command perf.c:401
      ev3dev#11 0x4e6215 in run_argv perf.c:448
      ev3dev#12 0x4e653a in main perf.c:555
      ev3dev#13 0x7f8454e4fa72 in __libc_start_main libc-2.32.so[3ea72]
      ev3dev#14 0x43a3ee in _start ??:0

The --overwrite option implies --tail-synthesize, which collects non-sample
events reflecting the system status when recording finishes. However, when
evsel opening fails (e.g., unsupported event 'cycles-ct'), session->evlist
is not initialized and remains NULL. The code unconditionally calls
record__synthesize() in the error path, which iterates through the NULL
evlist pointer and causes a segfault.

To fix it, move the record__synthesize() call inside the error check block, so
it's only called when there was no error during recording, ensuring that evlist
is properly initialized.

Fixes: 4ea648a ("perf record: Add --tail-synthesize option")
Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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4 participants