FYI, we noticed the following commit (built with gcc-7): commit: b6cb55961f641ffd67f34612f02e2f828d56ce00 ("[PATCH v2 1/2] mm/page_idle: Add per-pid idle page tracking using virtual indexing") url: https://github.com/0day-ci/linux/commits/Joel-Fernandes-Google/mm-page_idle-Add-per-pid-idle-page-tracking-using-virtual-indexing/20190728-105007 in testcase: kernel_selftests with following parameters: group: kselftests-02 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: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 8G caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): +-------------------------------------------------------------------------+------------+------------+ | | 43e317c1bb | b6cb55961f | +-------------------------------------------------------------------------+------------+------------+ | boot_successes | 32 | 2 | | boot_failures | 2 | 40 | | BUG:sleeping_function_called_from_invalid_context_at_kernel/workqueue.c | 2 | | | kernel_BUG_at_mm/slub.c | 0 | 40 | | invalid_opcode:#[##] | 0 | 40 | | RIP:kfree | 0 | 40 | | Kernel_panic-not_syncing:Fatal_exception | 0 | 40 | +-------------------------------------------------------------------------+------------+------------+ If you fix the issue, kindly add following tag Reported-by: kernel test robot [ 467.586509] kernel BUG at mm/slub.c:3948! [ 467.587827] invalid opcode: 0000 [#1] SMP PTI [ 467.589371] CPU: 1 PID: 25001 Comm: read Not tainted 5.3.0-rc1-00296-gb6cb55961f641f #6 [ 467.591837] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 [ 467.594835] RIP: 0010:kfree+0x193/0x1f0 [ 467.596622] Code: 48 01 df 29 c2 e8 5d fb 7d 00 8b 45 20 4c 89 34 03 e9 0e ff ff ff 49 8b 04 24 a9 00 00 01 00 75 0b 49 8b 44 24 08 a8 01 75 02 <0f> 0b 49 8b 04 24 31 f6 a9 00 00 01 00 74 06 41 0f b6 74 24 51 5b [ 467.603947] RSP: 0018:ffffb70b83a97d68 EFLAGS: 00010246 [ 467.606145] RAX: 0000000000000000 RBX: ffff98c3dda01680 RCX: ffff98c3dda01670 [ 467.608743] RDX: 0000000000000000 RSI: ffff98c3dda01690 RDI: ffff98c3dda01680 [ 467.610409] RBP: ffff98c3759b6000 R08: ffff98c47ffd2168 R09: fffff34246768008 [ 467.612224] R10: 00000000008b7000 R11: 0000000000000009 R12: fffff34246768040 [ 467.613983] R13: ffff98c3dda01670 R14: fffff34246b57200 R15: ffff98c3dda01660 [ 467.615736] FS: 00007fd0a0314500(0000) GS:ffff98c47fd00000(0000) knlGS:0000000000000000 [ 467.617624] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 467.619051] CR2: 000056310972e418 CR3: 00000001ad246000 CR4: 00000000000406e0 [ 467.620922] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 467.622760] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 467.624292] Call Trace: [ 467.625500] page_idle_proc_generic+0x2e0/0x420 [ 467.626849] ? page_really_idle+0x30/0x30 [ 467.628262] proc_page_idle_read+0x48/0x80 [ 467.629567] vfs_read+0x9b/0x160 [ 467.630646] ksys_read+0xa1/0xe0 [ 467.631806] do_syscall_64+0x5b/0x1f0 [ 467.633083] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 467.634513] RIP: 0033:0x7fd0a023c461 [ 467.635627] 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 [ 467.639758] RSP: 002b:00007ffff1b2ad18 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 467.641669] RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 00007fd0a023c461 [ 467.643314] RDX: 0000000000001000 RSI: 00007ffff1b2ad20 RDI: 0000000000000007 [ 467.645161] RBP: 0000563107763069 R08: 000000000000802f R09: 0000000000000078 [ 467.646982] R10: 0000000000000000 R11: 0000000000000246 R12: 0000563107763068 [ 467.648597] R13: 0000000000000001 R14: 00005631077630aa R15: 00005631096fe693 [ 467.650278] Modules linked in: sch_fq ip_vti ip6_vti fou6 sit ipip tunnel4 geneve act_mirred cls_basic sch_fq_codel esp6 authenc echainiv xt_policy iptable_filter veth netdevsim esp4 vxlan 8021q garp mrp bridge stp llc ip6_gre ip6_tunnel tunnel6 ip_gre gre cls_u32 sch_htb dummy fou ip6_udp_tunnel udp_tunnel ip_tunnel fuse rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver binfmt_misc sr_mod cdrom sg ata_generic pata_acpi intel_rapl_msr intel_rapl_common crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel ppdev bochs_drm drm_vram_helper ttm drm_kms_helper snd_pcm syscopyarea sysfillrect sysimgblt fb_sys_fops ata_piix aesni_intel crypto_simd snd_timer drm cryptd glue_helper snd libata soundcore pcspkr joydev serio_raw i2c_piix4 parport_pc floppy parport ip_tables [last unloaded: test_bpf] [ 467.666170] ---[ end trace e46f4da0708ece21 ]--- To reproduce: # build kernel cd linux cp config-5.3.0-rc1-00296-gb6cb55961f641f .config make HOSTCC=gcc-7 CC=gcc-7 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage git clone https://github.com/intel/lkp-tests.git cd lkp-tests bin/lkp qemu -k job-script # job-script is attached in this email Thanks, Rong Chen