Hi Oliver, Could you please help to validate the attached patch? The patch should fix this warning. (Please apply this patch on top of the whole patch series). Thanks. diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c index 65908880f424..ef32714cb182 100644 --- a/arch/x86/events/intel/ds.c +++ b/arch/x86/events/intel/ds.c @@ -2821,8 +2821,11 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs, struct perf_sample_d                  * If collision happened, the record will be dropped.                  */                 if (pebs_status != (1ULL << bit)) { -                       for_each_set_bit(i, (unsigned long *)&pebs_status, size) +                       for_each_set_bit(i, (unsigned long *)&pebs_status, size) {                                 error[i]++; +                               if (error[i] && !events[i]) +                                       events[i] = cpuc->events[i]; +                       }                         continue;                 } On 9/8/2025 5:05 PM, Mi, Dapeng wrote: > On 9/8/2025 4:43 PM, kernel test robot wrote: >> Hello, >> >> kernel test robot noticed "WARNING:at_arch/x86/events/intel/ds.c:#intel_pmu_drain_pebs_nhm" on: >> >> commit: a7138973beb1d124386472663cf50a571a2059ce ("[Patch v7 02/12] perf/x86/intel: Fix NULL event access and potential PEBS record loss") >> url: https://github.com/intel-lab-lkp/linux/commits/Dapeng-Mi/perf-x86-Remove-redundant-is_x86_event-prototype/20250828-094117 >> patch link: https://lore.kernel.org/all/20250828013435.1528459-3-dapeng1.mi@linux.intel.com/ >> patch subject: [Patch v7 02/12] perf/x86/intel: Fix NULL event access and potential PEBS record loss >> >> in testcase: phoronix-test-suite >> version: >> with following parameters: >> >> test: stress-ng-1.11.0 >> option_a: Socket Activity >> cpufreq_governor: performance >> >> >> >> config: x86_64-rhel-9.4 >> compiler: gcc-12 >> test machine: 96 threads 2 sockets Intel(R) Xeon(R) Gold 6252 CPU @ 2.10GHz (Cascade Lake) with 512G memory >> >> (please refer to attached dmesg/kmsg for entire log/backtrace) >> >> >> >> If you fix the issue in a separate patch/commit (i.e. not just a new version of >> the same patch/commit), kindly add following tags >> | Reported-by: kernel test robot >> | Closes: https://lore.kernel.org/oe-lkp/202509081646.d101cfb7-lkp@intel.com >> >> >> >> The kernel config and materials to reproduce are available at: >> https://download.01.org/0day-ci/archive/20250908/202509081646.d101cfb7-lkp@intel.com >> >> >> the dmesg in above link is not very clear, so we also attached one dmesg FYI, >> from which: >> >> [ 41.225784][ C82] ------------[ cut here ]------------ >> [ 41.225786][ C82] WARNING: CPU: 82 PID: 3704 at arch/x86/events/intel/ds.c:2592 intel_pmu_drain_pebs_nhm+0x56b/0x630 >> [ 41.225791][ C82] Modules linked in: xt_conntrack nft_chain_nat xt_MASQUERADE nf_nat nf_conntrack_netlink nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 >> xt_addrtype nft_compat nf_tables nfnetlink br_netfilter bridge stp llc dm_thin_pool dm_persistent_data dm_bio_prison dm_bufio qrtr sg binfmt_misc loop fus >> e dm_mod overlay btrfs blake2b_generic xor raid6_pq intel_rapl_msr intel_rapl_common intel_uncore_frequency intel_uncore_frequency_common skx_edac skx_eda >> c_common nfit libnvdimm x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irdma sd_mod ast irqbypass ice ipmi_ssif drm_client_lib snd_pcm ghash >> _clmulni_intel drm_shmem_helper snd_timer gnss rapl drm_kms_helper intel_cstate snd ahci ib_uverbs libahci mei_me soundcore acpi_power_meter i2c_i801 ioat >> dma drm ib_core pcspkr intel_uncore ipmi_si acpi_ipmi libata mei joydev i2c_smbus intel_pch_thermal lpc_ich dca wmi ipmi_devintf ipmi_msghandler acpi_pad >> [ 41.225831][ C82] CPU: 82 UID: 0 PID: 3704 Comm: sleep Tainted: G S 6.17.0-rc1-00052-ga7138973beb1 #1 VOLUNTARY >> [ 41.225834][ C82] Tainted: [S]=CPU_OUT_OF_SPEC >> [ 41.225835][ C82] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0008.031920191559 03/19/2019 >> [ 41.225836][ C82] RIP: 0010:intel_pmu_drain_pebs_nhm+0x56b/0x630 >> [ 41.225839][ C82] Code: 48 e8 b9 cd fe ff 85 c0 0f 84 a9 00 00 00 41 f6 84 24 a4 01 00 00 80 0f 84 9a 00 00 00 4c 89 ef e8 1a 2a 34 00 e9 c7 fc ff ff >> <0f> 0b e9 c0 fc ff ff 0f 0b e9 b9 fc ff ff 48 8b 04 cb 48 89 84 cc >> [ 41.225841][ C82] RSP: 0018:fffffe00012f38c0 EFLAGS: 00010046 >> [ 41.225843][ C82] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 >> [ 41.225844][ C82] RDX: 0000000000000001 RSI: 0000000000000004 RDI: fffffe00012f3900 >> [ 41.225845][ C82] RBP: fffffe00013120c8 R08: 0000000000000000 R09: 0000000000000000 >> [ 20.931889][ T1340] Error: Driver 'pcspkr' is already registered, aborting... >> [ 41.225846][ C82] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 >> [ 41.225847][ C82] R13: 0000000000000000 R14: fffffe00012f3c80 R15: 0000000000000000 >> [ 41.225848][ C82] FS: 0000000000000000(0000) GS:ffff88f027c62000(0000) knlGS:0000000000000000 >> [ 21.006859][ T1512] sd 6:0:0:0: Attached scsi generic sg0 type 0 >> [ 21.013583][ T1512] sd 7:0:0:0: Attached scsi generic sg1 type 0 >> [ 41.225849][ C82] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> [ 41.225851][ C82] CR2: 00007ffe5571fe7c CR3: 00000040c5ae1003 CR4: 00000000007726f0 >> [ 41.225852][ C82] PKRU: 55555554 >> [ 41.225853][ C82] Call Trace: >> [ 41.225855][ C82] >> [ 41.225861][ C82] handle_pmi_common+0x29b/0x430 >> [ 41.225865][ C82] intel_pmu_handle_irq+0x109/0x2b0 >> [ 41.225867][ C82] perf_event_nmi_handler+0x2a/0x70 >> [ 41.225870][ C82] nmi_handle+0x53/0x130 >> [ 41.225873][ C82] default_do_nmi+0x11d/0x170 >> [ 41.225876][ C82] exc_nmi+0x106/0x1b0 >> [ 41.225878][ C82] end_repeat_nmi+0xf/0x53 >> [ 41.225880][ C82] RIP: 0010:find_next_fd+0x2a/0xb0 >> [ 41.225883][ C82] Code: 0f 1f 44 00 00 41 54 89 f2 48 c7 c0 ff ff ff ff 49 89 fc 55 c1 ea 06 53 89 f3 48 8b 77 18 89 d9 48 d3 e0 48 f7 d0 48 0b 04 d6 >> <48> 83 f8 ff 74 0d 48 f7 d0 f3 48 0f bc c0 83 f8 3f 76 3a 41 8b 2c >> [ 41.225885][ C82] RSP: 0018:ffffc90025283b90 EFLAGS: 00000206 >> [ 41.225886][ C82] RAX: 0000000000000017 RBX: 0000000000000003 RCX: 0000000000000003 >> [ 41.225887][ C82] RDX: 0000000000000000 RSI: ffff88f06d277150 RDI: ffff88f06d2770e8 >> [ 41.225888][ C82] RBP: 0000000000000400 R08: 8080808080808080 R09: 979c8d9e9a8cdfff >> [ 41.225889][ C82] R10: fefefefefefefeff R11: 0000000000000000 R12: ffff88f06d2770e8 >> [ 41.225890][ C82] R13: 0000000000088000 R14: ffff88f06d2770c0 R15: ffff88f06d2770e8 >> [ 41.225893][ C82] ? find_next_fd+0x2a/0xb0 >> [ 41.225896][ C82] ? find_next_fd+0x2a/0xb0 >> [ 41.225899][ C82] >> [ 41.225899][ C82] >> [ 41.225900][ C82] alloc_fd+0x55/0x130 >> [ 41.225902][ C82] do_sys_openat2+0x5a/0xf0 >> [ 41.225905][ C82] __x64_sys_openat+0x6d/0xb0 >> [ 41.225907][ C82] do_syscall_64+0x7f/0x2b0 >> [ 41.225909][ C82] ? vfs_statx+0x68/0x170 >> [ 41.225911][ C82] ? strncpy_from_user+0x26/0xf0 >> [ 41.225914][ C82] ? vfs_fstatat+0x75/0xb0 >> [ 41.225917][ C82] ? __do_sys_newfstatat+0x25/0x70 >> [ 41.225919][ C82] ? path_openat+0xb6/0x2b0 >> [ 41.225921][ C82] ? do_syscall_64+0x7f/0x2b0 >> [ 41.225922][ C82] ? do_filp_open+0xc3/0x170 >> [ 41.225924][ C82] ? do_syscall_64+0x7f/0x2b0 >> [ 41.225925][ C82] ? __cond_resched+0x1e/0x70 >> [ 41.225928][ C82] ? check_heap_object+0x34/0x1b0 >> [ 41.225931][ C82] ? __check_object_size+0x5c/0x130 >> [ 41.225933][ C82] ? do_sys_openat2+0x8a/0xf0 >> [ 41.225936][ C82] ? __x64_sys_openat+0x6d/0xb0 >> [ 41.225938][ C82] ? clear_bhb_loop+0x30/0x80 >> [ 41.225940][ C82] ? clear_bhb_loop+0x30/0x80 >> [ 41.225942][ C82] entry_SYSCALL_64_after_hwframe+0x76/0x7e >> [ 41.225944][ C82] RIP: 0033:0x7eff04bb9a2d >> [ 41.225946][ C82] Code: 48 89 54 24 e0 41 83 e2 40 75 32 89 f0 25 00 00 41 00 3d 00 00 41 00 74 24 89 f2 b8 01 01 00 00 48 89 fe bf 9c ff ff ff 0f 05 >> <48> 3d 00 f0 ff ff 77 33 c3 66 2e 0f 1f 84 00 00 00 00 00 48 8d 44 >> [ 41.225947][ C82] RSP: 002b:00007ffe5571f7e8 EFLAGS: 00000287 ORIG_RAX: 0000000000000101 >> [ 41.225949][ C82] RAX: ffffffffffffffda RBX: 0000558b3236dbe6 RCX: 00007eff04bb9a2d >> [ 41.225950][ C82] RDX: 0000000000080000 RSI: 00007eff04bc20b1 RDI: 00000000ffffff9c >> [ 41.225951][ C82] RBP: 00007eff04bcd1f8 R08: 0000000000000000 R09: 0000558b3236dbe6 >> [ 41.225952][ C82] R10: 0000000000000000 R11: 0000000000000287 R12: ffffffffffffffff >> [ 41.225953][ C82] R13: 0000000000000001 R14: 00007eff04bcc020 R15: 00007eff04bcd6b8 >> [ 41.225954][ C82] >> [ 41.225955][ C82] ---[ end trace 0000000000000000 ]--- >> >> > It looks the warning is triggered in the  "error[i] != 0" case and lead to > the local events[] array is not initialized. Would fix it in next version. > > > >