Greeting, FYI, we noticed the following commit (built with gcc-9): commit: e655d17ffada57d11a82336a43fd91dd9c2ecbd2 ("[PATCH] mm: introduce sysctl file to flush per-cpu vmstat statistics") url: https://github.com/0day-ci/linux/commits/Marcelo-Tosatti/mm-introduce-sysctl-file-to-flush-per-cpu-vmstat-statistics/20201118-002950 base: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git 9c87c9f41245baa3fc4716cf39141439cf405b01 in testcase: kernel-selftests version: kernel-selftests-x86_64-b5a583fb-1_20201015 with following parameters: group: group-02 ucode: 0xe2 test-description: The kernel contains a set of "self tests" under the tools/testing/selftests/ directory. These are intended to be small unit tests to exercise individual code paths in the kernel. test-url: https://www.kernel.org/doc/Documentation/kselftest.txt on test machine: 4 threads Intel(R) Core(TM) i5-6500 CPU @ 3.20GHz with 32G memory caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): If you fix the issue, kindly add following tag Reported-by: kernel test robot kern :err : [ 318.711546] BUG: using smp_processor_id() in preemptible [00000000] code: read/27945 kern :warn : [ 318.719301] caller is proc_quiet_vmstat+0x44/0x80 kern :warn : [ 318.724037] CPU: 1 PID: 27945 Comm: read Not tainted 5.10.0-rc4-00068-ge655d17ffada #1 kern :warn : [ 318.731971] Hardware name: Dell Inc. OptiPlex 7040/0Y7WYT, BIOS 1.8.1 12/05/2017 kern :warn : [ 318.739377] Call Trace: kern :warn : [ 318.741824] dump_stack+0x8d/0xb5 kern :warn : [ 318.745140] check_preemption_disabled+0xc3/0xe0 kern :warn : [ 318.749761] proc_quiet_vmstat+0x44/0x80 kern :warn : [ 318.753684] __cgroup_bpf_run_filter_sysctl+0xa4/0x580 kern :warn : [ 318.758834] proc_sys_call_handler+0x20f/0x260 kern :warn : [ 318.763282] new_sync_read+0x11b/0x1a0 kern :warn : [ 318.767039] vfs_read+0x16d/0x1e0 kern :warn : [ 318.770381] ksys_read+0x68/0xe0 kern :warn : [ 318.773612] do_syscall_64+0x33/0x40 kern :warn : [ 318.777188] entry_SYSCALL_64_after_hwframe+0x44/0xa9 kern :warn : [ 318.782241] RIP: 0033:0x7fe113db4461 kern :warn : [ 318.785816] Code: fe ff ff 50 48 8d 3d fe d0 09 00 e8 e9 03 02 00 66 0f 1f 84 00 00 00 00 00 48 8d 05 99 62 0d 00 8b 00 85 c0 75 13 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 57 c3 66 0f 1f 44 00 00 41 54 49 89 d4 55 48 kern :warn : [ 318.804587] RSP: 002b:00007ffdfe04a328 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 kern :warn : [ 318.812158] RAX: ffffffffffffffda RBX: 0000000000000008 RCX: 00007fe113db4461 kern :warn : [ 318.819293] RDX: 0000000000001000 RSI: 00007ffdfe04a330 RDI: 0000000000000008 kern :warn : [ 318.826430] RBP: 0000559d31881039 R08: 0000000000000003 R09: 0000000000000078 kern :warn : [ 318.833565] R10: 0000000000000000 R11: 0000000000000246 R12: 0000559d31881038 kern :warn : [ 318.840704] R13: 0000000000000002 R14: 0000559d3188107a R15: 0000559d32a6f9db kern :err : [ 318.847944] BUG: using smp_processor_id() in preemptible [00000000] code: read/27945 kern :warn : [ 318.855728] caller is proc_quiet_vmstat+0x44/0x80 kern :warn : [ 318.860612] CPU: 1 PID: 27945 Comm: read Not tainted 5.10.0-rc4-00068-ge655d17ffada #1 kern :warn : [ 318.868542] Hardware name: Dell Inc. OptiPlex 7040/0Y7WYT, BIOS 1.8.1 12/05/2017 kern :warn : [ 318.875938] Call Trace: kern :warn : [ 318.878387] dump_stack+0x8d/0xb5 kern :warn : [ 318.881706] check_preemption_disabled+0xc3/0xe0 kern :warn : [ 318.886341] proc_quiet_vmstat+0x44/0x80 kern :warn : [ 318.890278] proc_sys_call_handler+0x13e/0x260 kern :warn : [ 318.894728] new_sync_read+0x11b/0x1a0 kern :warn : [ 318.898486] vfs_read+0x16d/0x1e0 kern :warn : [ 318.901804] ksys_read+0x68/0xe0 kern :warn : [ 318.905035] do_syscall_64+0x33/0x40 kern :warn : [ 318.908612] entry_SYSCALL_64_after_hwframe+0x44/0xa9 kern :warn : [ 318.913662] RIP: 0033:0x7fe113db4461 kern :warn : [ 318.917237] Code: fe ff ff 50 48 8d 3d fe d0 09 00 e8 e9 03 02 00 66 0f 1f 84 00 00 00 00 00 48 8d 05 99 62 0d 00 8b 00 85 c0 75 13 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 57 c3 66 0f 1f 44 00 00 41 54 49 89 d4 55 48 kern :warn : [ 318.936009] RSP: 002b:00007ffdfe04a328 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 kern :warn : [ 318.943578] RAX: ffffffffffffffda RBX: 0000000000000008 RCX: 00007fe113db4461 kern :warn : [ 318.950715] RDX: 0000000000001000 RSI: 00007ffdfe04a330 RDI: 0000000000000008 kern :warn : [ 318.957849] RBP: 0000559d31881039 R08: 0000000000000003 R09: 0000000000000078 kern :warn : [ 318.964982] R10: 0000000000000000 R11: 0000000000000246 R12: 0000559d31881038 kern :warn : [ 318.972116] R13: 0000000000000002 R14: 0000559d3188107a R15: 0000559d32a6f9db kern :info : [ 319.061697] sysrq: HELP : loglevel(0-9) reboot(b) crash(c) show-all-locks(d) terminate-all-tasks(e) memory-full-oom-kill(f) kill-all-tasks(i) thaw-filesystems(j) sak(k) show-backtrace-all-active-cpus(l) show-memory-usage(m) nice-all-RT-tasks(n) poweroff(o) show-registers(p) show-all-timers(q) unraw(r) sync(s) show-task-states(t) unmount(u) show-blocked-tasks(w) dump-ftrace-buffer(z) user :notice: [ 321.570463] ok 12 selftests: proc: read user :notice: [ 321.577830] # selftests: proc: self user :notice: [ 321.599985] ok 13 selftests: proc: self user :notice: [ 321.606065] # selftests: proc: setns-dcache user :notice: [ 321.627516] ok 14 selftests: proc: setns-dcache user :notice: [ 321.634335] # selftests: proc: setns-sysvipc user :notice: [ 321.655104] ok 15 selftests: proc: setns-sysvipc user :notice: [ 321.662039] # selftests: proc: thread-self user :notice: [ 321.682210] ok 16 selftests: proc: thread-self user :notice: [ 321.689137] # selftests: proc: proc-multiple-procfs user :notice: [ 321.710024] ok 17 selftests: proc: proc-multiple-procfs user :notice: [ 321.717763] # selftests: proc: proc-fsconfig-hidepid user :notice: [ 321.737068] ok 18 selftests: proc: proc-fsconfig-hidepid user :notice: [ 321.745566] make: warning: Clock skew detected. Your build may be incomplete. user :notice: [ 321.757738] make: Leaving directory '/usr/src/perf_selftests-x86_64-rhel-7.6-kselftests-e655d17ffada57d11a82336a43fd91dd9c2ecbd2/tools/testing/selftests/proc' kern :info : [ 321.792514] ramoops: using module parameters kern :info : [ 321.798332] pstore: Using crash dump compression: deflate kern :info : [ 321.804336] printk: console [ramoops-1] enabled kern :info : [ 321.809491] pstore: Registered ramoops as persistent store backend kern :info : [ 321.815684] ramoops: using 0xf4240@0x8000000, ecc: 0 user :notice: [ 321.827756] 2019-02-14 10:16:47 make run_tests -C pstore user :notice: [ 321.857425] make: Entering directory '/usr/src/perf_selftests-x86_64-rhel-7.6-kselftests-e655d17ffada57d11a82336a43fd91dd9c2ecbd2/tools/testing/selftests/pstore' user :notice: [ 321.875269] make: Warning: File '../lib.mk' has modification time 55836578 s in the future user :notice: [ 321.885765] TAP version 13 user :notice: [ 321.890482] 1..2 user :notice: [ 321.894762] # selftests: pstore: pstore_tests user :notice: [ 321.903480] # === Pstore unit tests (pstore_tests) === user :notice: [ 321.911204] # UUID=a6a480bd-f511-418e-83f0-0c625840f032 user :notice: [ 321.919011] # Checking pstore backend is registered ... ok user :notice: [ 321.926522] # backend=ramoops user :notice: [ 325.968623] # cmdline=ip=::::lkp-skl-d05::dhcp root=/dev/ram0 user=lkp job=/lkp/jobs/scheduled/lkp-skl-d05/kernel-selftests-group-02-ucode=0xe2-debian-10.4-x86_64-20200603.cgz-e655d17ffada57d11a82336a43fd91dd9c2ecbd2-20201122-19793-14arzjn-2.yaml ARCH=x86_64 kconfig=x86_64-rhel-7.6-kselftests branch=linux-review/Marcelo-Tosatti/mm-introduce-sysctl-file-to-flush-per-cpu-vmstat-statistics/20201118-002950 commit=e655d17ffada57d11a82336a43fd91dd9c2ecbd2 BOOT_IMAGE=/pkg/linux/x86_64-rhel-7.6-kselftests/gcc-9/e655d17ffada57d11a82336a43fd91dd9c2ecbd2/vmlinuz-5.10.0-rc4-00068-ge655d17ffada erst_disable max_uptime=3600 RESULT_ROOT=/result/kernel-selftests/group-02-ucode=0xe2/lkp-skl-d05/debian-10.4-x86_64-20200603.cgz/x86_64-rhel-7.6-kselftests/gcc-9/e655d17ffada57d11a82336a43fd91dd9c2ecbd2/3 LKP_SERVER=internal-lkp-server nokaslr selinux=0 debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeou user :notice: [ 328.399180] # Checking pstore console is registered ... ok user :notice: [ 328.406998] # Checking /dev/pmsg0 exists ... ok user :notice: [ 328.414030] # Writing unique string to /dev/pmsg0 ... ok user :notice: [ 328.421763] ok 1 selftests: pstore: pstore_tests user :notice: [ 328.428885] # selftests: pstore: pstore_post_reboot_tests user :notice: [ 328.818409] # === Pstore unit tests (pstore_post_reboot_tests) === user :notice: [ 328.827075] # UUID=5d84a735-2106-4f87-b7dd-61334ca4ce96 user :notice: [ 328.834896] # Checking pstore backend is registered ... ok user :notice: [ 328.842335] # backend=ramoops user :notice: [ 341.500511] # cmdline=ip=::::lkp-skl-d05::dhcp root=/dev/ram0 user=lkp job=/lkp/jobs/scheduled/lkp-skl-d05/kernel-selftests-group-02-ucode=0xe2-debian-10.4-x86_64-20200603.cgz-e655d17ffada57d11a82336a43fd91dd9c2ecbd2-20201122-19793-14arzjn-2.yaml ARCH=x86_64 kconfig=x86_64-rhel-7.6-kselftests branch=linux-review/Marcelo-Tosatti/mm-introduce-sysctl-file-to-flush-per-cpu-vmstat-statistics/20201118-002950 commit=e655d17ffada57d11a82336a43fd91dd9c2ecbd2 BOOT_IMAGE=/pkg/linux/x86_64-rhel-7.6-kselftests/gcc-9/e655d17ffada57d11a82336a43fd91dd9c2ecbd2/vmlinuz-5.10.0-rc4-00068-ge655d17ffada erst_disable max_uptime=3600 RESULT_ROOT=/result/kernel-selftests/group-02-ucode=0xe2/lkp-skl-d05/debian-10.4-x86_64-20200603.cgz/x86_64-rhel-7.6-kselftests/gcc-9/e655d17ffada57d11a82336a43fd91dd9c2ecbd2/3 LKP_SERVER=internal-lkp-server nokaslr selinux=0 debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeou user :notice: [ 345.010149] # pstore_crash_test has not been executed yet. we skip further tests. To reproduce: git clone https://github.com/intel/lkp-tests.git cd lkp-tests bin/lkp install job.yaml # job file is attached in this email bin/lkp run job.yaml Thanks, Oliver Sang