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X-Proofpoint-ORIG-GUID: UT2T8Cyc7TwrE_mPxAunJctOQMJGEYfV X-Proofpoint-GUID: UT2T8Cyc7TwrE_mPxAunJctOQMJGEYfV X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwNjMwMDE0MSBTYWx0ZWRfX6zh9FMtRmfxL PHH9ybbt8HjnU2SCAxhKOY5vcnQ4A4laDBVlVcepJmB8pLgng8tj1XtMQWXWTf4lRaEfjPy3Q// nWWkqoohwfHePJJmBG8o1kJApXfaRN5jKZQ0j29kjkBfdWxm1LsupWnV2KEpEMk+5NcZoiaTm9D JBRErdN4Jbxnr99Cjicx+fyTZMcA0ZvynXjvOTJ1UsBn507EKbIhKsFltRhONtf/JqIN3P+vPxG w/fU6mtTbYCw729sE8KWS6b5kExZViAVM93LJjX1vgyqBE/TqJvLtxXHWtEqSexfLAzXJsDlPJ1 elugB8+SX7etQl1t/p08WxHBj6PXZjJP+Dhs+Jzd96oxiA5AQqfNDEMzw1cqVPHnHdv5Sk2u83f zEU8AWglNSN9D1TEXe1InD9Q3a2V5yTGplDA8Un4G67vVgUSNAqz0D3vNL/D8i+UX6sQrP1Y X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.1.7,FMLib:17.12.80.40 definitions=2025-06-30_04,2025-06-27_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 bulkscore=0 priorityscore=1501 malwarescore=0 suspectscore=0 mlxscore=0 spamscore=0 adultscore=0 lowpriorityscore=0 phishscore=0 clxscore=1011 mlxlogscore=811 classifier=spam authscore=0 authtc=n/a authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2505280000 definitions=main-2506300141 It is possible that perf_trace_sched_switch call is rescheduled causing NULL access in perf_trace_buf_alloc because of perf_trace_event_unreg called in between, leading to data abort: [ 363.202351][ T0] Unable to handle kernel paging request at virtual ad= dress ffffffba56d0a03c [ 363.202355][ T0] Mem abort info: [ 363.202355][ T0] ESR =3D 0x0000000096000045 [ 363.202357][ T0] EC =3D 0x25: DABT (current EL), IL =3D 32 bits [ 363.202359][ T0] SET =3D 0, FnV =3D 0 [ 363.202360][ T0] EA =3D 0, S1PTW =3D 0 [ 363.202361][ T0] FSC =3D 0x05: level 1 translation fault [ 363.202363][ T0] Data abort info: [ 363.202364][ T0] ISV =3D 0, ISS =3D 0x00000045, ISS2 =3D 0x00000000 [ 363.202365][ T0] CM =3D 0, WnR =3D 1, TnD =3D 0, TagAccess =3D 0 [ 363.202367][ T0] GCS =3D 0, Overlay =3D 0, DirtyBit =3D 0, Xs =3D 0 [ 363.202369][ T0] swapper pgtable: 4k pages, 39-bit VAs, pgdp=3D000000= 00c9795000 [ 363.202371][ T0] [ffffffba56d0a03c] pgd=3D0000000000000000, p4d=3D000= 0000000000000, pud=3D0000000000000000 [ 363.202377][ T0] Internal error: Oops: 0000000096000045 [#1] PREEMPT = SMP [ 363.202383][ T0] Dumping ftrace buffer: [ 363.202385][ T0] (ftrace buffer empty) =2E =2E [ 363.203036][ T0] CPU: 4 UID: 0 PID: 0 Comm: swapper/4 Tainted: G W O= \ 6.12.23-android16-5-maybe-dirty-4k #1 6d534d25cf9b12caecb741d5004c181a6a43= 2b53 [ 363.203042][ T0] Tainted: [W]=3DWARN, [O]=3DOOT_MODULE [ 363.203045][ T0] pstate: 834000c5 (Nzcv daIF +PAN -UAO +TCO +DIT -SSB= S BTYPE=3D--) [ 363.203048][ T0] pc : perf_trace_buf_alloc+0x90/0xe0 [ 363.203057][ T0] lr : perf_trace_buf_alloc+0x40/0xe0 [ 363.203060][ T0] sp : ffffffc08016bc90 [ 363.203062][ T0] x29: ffffffc08016bc90 x28: 0000000000000000 x27: fff= fff88083d0000 [ 363.203066][ T0] x26: ffffffba56d0a000 x25: 00000044684e8bd8 x24: 119= 8f2d01457f4e4 [ 363.203070][ T0] x23: 0000000000000000 x22: ffffff88083d0000 x21: fff= fffc08016bccc [ 363.203073][ T0] x20: ffffffc08016bcd0 x19: 0000000000000044 x18: fff= fffd01580bec0 [ 363.203077][ T0] x17: 00000000d2dc9ceb x16: 00000000d2dc9ceb x15: 000= 0000000000010 [ 363.203080][ T0] x14: 0000000000000100 x13: 0000000000000100 x12: 000= 0000000000100 [ 363.203083][ T0] x11: 0000000000ff0100 x10: 0000000000000001 x9 : fff= fffba56d0a000 [ 363.203087][ T0] x8 : ffffffba56d0a044 x7 : 0000000000000001 x6 : 000= 000548fd2bf93 [ 363.203090][ T0] x5 : 00000054908be990 x4 : 0000000000000000 x3 : fff= fff8808329640 [ 363.203094][ T0] x2 : ffffffc08016bccc x1 : ffffffc08016bcd0 x0 : fff= fffba56d0a000 [ 363.203097][ T0] Call trace: [ 363.203098][ T0] perf_trace_buf_alloc+0x90/0xe0 [ 363.203102][ T0] perf_trace_sched_switch+0x74/0x190 [ 363.203107][ T0] __schedule+0xbb0/0xeac [ 363.203112][ T0] schedule_idle+0x24/0x48 [ 363.203114][ T0] do_idle+0x214/0x25c [ 363.203117][ T0] cpu_startup_entry+0x34/0x3c [ 363.203119][ T0] secondary_start_kernel+0x130/0x150 [ 363.203124][ T0] __secondary_switched+0xc0/0xc4 [ 363.203129][ T0] Code: f8605908 d538d089 8b080120 8b33c008 (f81f811f) [ 363.203131][ T0] ---[ end trace 0000000000000000 ]--- [ 363.203133][ T0] Kernel panic - not syncing: Oops: Fatal exception [ 363.203135][ T0] SMP: stopping secondary CPUs [ 363.203276][ T0] [ 363.203276][ T0] Total active clients count: 0 [ 363.203280][ T0] Dumping ftrace buffer: [ 363.203281][ T0] (ftrace buffer empty) Fix the issue by disabling preemption in perf_trace calls. Signed-off-by: Aditya Chillara --- Change-Id: I787347a7db4554cfd2cb74e0fc985699f1824c92 --- include/trace/perf.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/include/trace/perf.h b/include/trace/perf.h index 5800d13146c3d0cdf4eb474a3bb895dd71753de4..76994a5d8c55f4ca071070ff551= a53a84fb1d95c 100644 --- a/include/trace/perf.h +++ b/include/trace/perf.h @@ -66,6 +66,8 @@ perf_trace_##call(void *__data, proto) \ int __data_size; \ int rctx; \ \ + guard(preempt_notrace)(); \ + \ __data_size =3D trace_event_get_offsets_##call(&__data_offsets, args); \ \ head =3D this_cpu_ptr(event_call->perf_events); \ --- base-commit: 70575e77839f4c5337ce2653b39b86bb365a870e change-id: 20250630-fix-perf-trace-null-access-9661f910df72 Best regards, --=20 Aditya Chillara