FYI, we noticed the following commit (built with gcc-7): commit: 22f657e2876612270ad346b7f5ba2493ba434d41 ("[PATCH 12/15] blkcg: cleanup and make blk_get_rl use blkg_lookup_create") url: https://github.com/0day-ci/linux/commits/Dennis-Zhou/blkcg-ref-count-refactor-cleanup-blkcg-avg_lat/20180831-161742 base: https://git.kernel.org/cgit/linux/kernel/git/axboe/linux-block.git for-next in testcase: trinity with following parameters: runtime: 300s test-description: Trinity is a linux system call fuzz tester. test-url: http://codemonkey.org.uk/projects/trinity/ on test machine: qemu-system-x86_64 -enable-kvm -cpu Haswell,+smep,+smap -smp 2 -m 512M caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): +------------------------------------------------------------------+------------+------------+ | | f743a58719 | 22f657e287 | +------------------------------------------------------------------+------------+------------+ | boot_successes | 3 | 0 | | boot_failures | 10 | 16 | | invoked_oom-killer:gfp_mask=0x | 6 | 6 | | Mem-Info | 6 | 6 | | Kernel_panic-not_syncing:Out_of_memory_and_no_killable_processes | 6 | 6 | | IP-Config:Auto-configuration_of_network_failed | 4 | | | general_protection_fault:#[##] | 0 | 10 | | RIP:get_request | 0 | 10 | | Kernel_panic-not_syncing:Fatal_exception | 0 | 10 | +------------------------------------------------------------------+------------+------------+ [ 93.607840] SCSI Media Changer driver v0.25 [ 93.667470] scsi host0: scsi_debug: version 0188 [20180128] [ 93.667470] dev_size_mb=8, opts=0x0, submit_queues=1, statistics=0 [ 93.756552] kasan: CONFIG_KASAN_INLINE enabled [ 93.766196] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 93.766196] general protection fault: 0000 [#1] PREEMPT KASAN [ 93.766196] CPU: 0 PID: 27 Comm: kworker/u2:1 Not tainted 4.19.0-rc1-00174-g22f657e #1 [ 93.766196] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 [ 93.766196] Workqueue: events_unbound async_run_entry_fn [ 93.766196] RIP: 0010:get_request+0x11f/0xe24 [ 93.766196] Code: 83 b8 f0 00 00 00 00 74 02 0f 0b e8 6b 78 46 ff 48 8b 44 24 10 48 8d 78 60 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 74 05 e8 6d 16 63 ff 48 8b 44 24 10 48 bd 00 00 00 00 [ 93.766196] RSP: 0000:ffff880016c07850 EFLAGS: 00010006 [ 93.766196] RAX: dffffc0000000000 RBX: dffffc0000000000 RCX: 0000000000000008 [ 93.766196] RDX: 000000000000000c RSI: 0000000000000020 RDI: 0000000000000060 [ 93.766196] RBP: ffff88001463b390 R08: 0000000000600000 R09: ffffed0002d80f0f [ 93.766196] R10: 0000000000000000 R11: ffff880016c07877 R12: 0000000000600000 [ 93.766196] R13: 0000000000000000 R14: 0000000000000020 R15: ffff880014639540 [ 93.766196] FS: 0000000000000000(0000) GS:ffffffff8427e000(0000) knlGS:0000000000000000 [ 93.766196] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 93.766196] CR2: 0000000000000000 CR3: 000000000422c001 CR4: 00000000000206b0 [ 93.766196] Call Trace: [ 93.766196] ? blk_rq_init+0x27c/0x27c [ 93.766196] ? blk_exit_rl+0x55/0x55 [ 93.766196] ? __wake_up_common_lock+0x140/0x140 [ 93.766196] ? tracer_preempt_on+0x16/0x25 [ 93.766196] ? preempt_count_sub+0x12d/0x136 [ 93.766196] ? task_unlock+0xa/0x1a [ 93.766196] ? create_task_io_context+0x2c7/0x2cf [ 93.766196] blk_get_request+0x14d/0x277 [ 93.766196] __scsi_execute+0x67/0x466 [ 93.766196] scsi_probe_and_add_lun+0x399/0x1d14 [ 93.766196] ? rpm_resume+0xad5/0xb05 [ 93.766196] ? scsi_sanitize_inquiry_string+0x77/0x77 [ 93.766196] ? rpm_put_suppliers+0x10e/0x10e [ 93.766196] ? scsi_target_reap_ref_release+0x6a/0x6a [ 93.766196] ? tracer_preempt_on+0x16/0x25 [ 93.766196] ? preempt_count_sub+0x12d/0x136 [ 93.766196] __scsi_scan_target+0x130/0x6af [ 93.766196] ? __free_pages+0x3c/0x3c [ 93.766196] ? scsi_probe_and_add_lun+0x1d14/0x1d14 [ 93.766196] ? rpm_resume+0xad5/0xb05 [ 93.766196] ? rpm_put_suppliers+0x10e/0x10e [ 93.766196] ? __switch_to_asm+0x30/0x60 [ 93.766196] ? ___might_sleep+0xac/0x33e [ 93.766196] scsi_scan_channel+0xcb/0xe8 [ 93.766196] scsi_scan_host_selected+0x1ca/0x201 [ 93.766196] ? do_scsi_scan_host+0x18a/0x18a [ 93.766196] do_scan_async+0x3e/0x2ff [ 93.766196] ? do_scsi_scan_host+0x18a/0x18a [ 93.766196] async_run_entry_fn+0x1c5/0x33c [ 93.766196] process_one_work+0x4c0/0x6cd [ 93.766196] ? preempt_count_sub+0x12d/0x136 [ 93.766196] worker_thread+0x4b3/0x610 [ 93.766196] ? __kthread_parkme+0x9f/0x148 [ 93.766196] kthread+0x2c5/0x2d4 [ 93.766196] ? process_scheduled_works+0x6d/0x6d [ 93.766196] ? __kthread_cancel_work+0x16b/0x16b [ 93.766196] ret_from_fork+0x35/0x40 [ 93.766196] ---[ end trace a8869917661828b0 ]--- [ 93.766196] RIP: 0010:get_request+0x11f/0xe24 [ 93.766196] Code: 83 b8 f0 00 00 00 00 74 02 0f 0b e8 6b 78 46 ff 48 8b 44 24 10 48 8d 78 60 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 74 05 e8 6d 16 63 ff 48 8b 44 24 10 48 bd 00 00 00 00 [ 93.766196] RSP: 0000:ffff880016c07850 EFLAGS: 00010006 [ 93.766196] RAX: dffffc0000000000 RBX: dffffc0000000000 RCX: 0000000000000008 [ 93.766196] RDX: 000000000000000c RSI: 0000000000000020 RDI: 0000000000000060 [ 93.766196] RBP: ffff88001463b390 R08: 0000000000600000 R09: ffffed0002d80f0f [ 93.766196] R10: 0000000000000000 R11: ffff880016c07877 R12: 0000000000600000 [ 93.766196] R13: 0000000000000000 R14: 0000000000000020 R15: ffff880014639540 [ 93.766196] FS: 0000000000000000(0000) GS:ffffffff8427e000(0000) knlGS:0000000000000000 [ 93.766196] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 93.766196] CR2: 0000000000000000 CR3: 000000000422c001 CR4: 00000000000206b0 [ 93.766196] Kernel panic - not syncing: Fatal exception [ 93.766196] Kernel Offset: disabled Elapsed time: 100 #!/bin/bash To reproduce: 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