INFO: task syz-executor167:8440 blocked for more than 143 seconds. Not tainted 5.14.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor167 state:D stack:23384 pid: 8440 ppid: 8439 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4683 [inline] __schedule+0xc07/0x11f0 kernel/sched/core.c:5940 schedule+0x14b/0x210 kernel/sched/core.c:6019 schedule_timeout+0x98/0x2f0 kernel/time/timer.c:1855 do_wait_for_common+0x2da/0x480 kernel/sched/completion.c:85 __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x48/0x60 kernel/sched/completion.c:138 flush_workqueue+0x75d/0x1750 kernel/workqueue.c:2839 nbd_start_device_ioctl drivers/block/nbd.c:1350 [inline] __nbd_ioctl drivers/block/nbd.c:1411 [inline] nbd_ioctl+0x853/0xa20 drivers/block/nbd.c:1451 blkdev_ioctl+0x332/0x690 block/ioctl.c:585 block_ioctl+0xae/0xf0 fs/block_dev.c:1604 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:1055 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4441e9 RSP: 002b:00007ffdcb6581f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004004a0 RCX: 00000000004441e9 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffdcb658398 R09: 00007ffdcb658398 R10: 00007ffdcb658398 R11: 0000000000000246 R12: 0000000000403500 R13: 431bde82d7b634db R14: 00000000004b2018 R15: 00000000004004a0 Showing all locks held in the system: 1 lock held by khungtaskd/1642: #0: ffffffff8c717d80 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 arch/x86/pci/mmconfig_64.c:151 2 locks held by kworker/u5:0/2026: #0: ffff88801f178138 ((wq_completion)knbd0-recv){+.+.}-{0:0}, at: process_one_work+0x7aa/0x10c0 kernel/workqueue.c:2249 #1: ffffc900075afd20 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x7e8/0x10c0 kernel/workqueue.c:2251 1 lock held by in:imklog/8139: #0: ffff88801fe02370 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x2f0 fs/file.c:974 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1642 Comm: khungtaskd Not tainted 5.14.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1d3/0x29f lib/dump_stack.c:105 nmi_cpu_backtrace+0x16c/0x190 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x191/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xd06/0xd50 kernel/hung_task.c:295 kthread+0x453/0x480 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4845 Comm: systemd-journal Not tainted 5.14.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:50 [inline] RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:173 [inline] RIP: 0010:unwind_next_frame+0x4e8/0x1fa0 arch/x86/kernel/unwind_orc.c:443 Code: 00 e9 90 13 00 00 4c 89 f5 4d 89 f7 66 0f 1f 44 00 00 4c 89 e8 4c 29 f8 48 89 c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83 e0 fe <49> 8d 1c 47 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f RSP: 0018:ffffc9000164f8c0 EFLAGS: 00000202 RAX: 0000000000000002 RBX: ffffffff8dcf20c4 RCX: 0000000000000003 RDX: ffffffff8e3a94ca RSI: ffffffff81c95979 RDI: ffffffff81386e59 RBP: ffffffff8dcf20b4 R08: 0000000000000013 R09: ffffc9000164fa50 R10: fffff520002c9f3c R11: 0000000000000000 R12: ffffffff81c95978 R13: ffffffff8dcf20c0 R14: ffffffff8dcf20b4 R15: ffffffff8dcf20b4 FS: 00007fa54e0bc8c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa54b48c000 CR3: 0000000017c15000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0xb2/0xe0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x104/0x1e0 kernel/stacktrace.c:121 kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x3d/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0x109/0x150 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1625 [inline] slab_free_freelist_hook+0x1d8/0x290 mm/slub.c:1650 slab_free mm/slub.c:3210 [inline] kmem_cache_free+0x85/0x170 mm/slub.c:3226 file_free fs/file_table.c:55 [inline] __fput+0x563/0x7b0 fs/file_table.c:298 task_work_run+0x146/0x1c0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x201/0x220 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x26/0x60 kernel/entry/common.c:302 do_syscall_64+0x4c/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fa54d64b840 Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 RSP: 002b:00007ffcc48f6218 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: fffffffffffffffe RBX: 00007ffcc48f6520 RCX: 00007fa54d64b840 RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 000055da0e2262f0 RBP: 000000000000000d R08: 000000000000c0c1 R09: 00000000ffffffff R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff R13: 000055da0e21a040 R14: 00007ffcc48f64e0 R15: 000055da0e226110