INFO: task systemd-udevd:2973 blocked for more than 143 seconds. Not tainted 5.16.0-rc1-next-20211118-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:systemd-udevd state:D stack:22616 pid: 2973 ppid: 1 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:4987 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6268 schedule+0xd2/0x260 kernel/sched/core.c:6341 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6400 __mutex_lock_common kernel/locking/mutex.c:680 [inline] __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740 blkdev_get_by_dev.part.0+0x9b/0xb50 block/bdev.c:819 blkdev_get_by_dev+0x6b/0x80 block/bdev.c:859 blkdev_open+0x154/0x2e0 block/fops.c:501 do_dentry_open+0x4c8/0x1250 fs/open.c:822 do_open fs/namei.c:3426 [inline] path_openat+0x1cad/0x2750 fs/namei.c:3559 do_filp_open+0x1aa/0x400 fs/namei.c:3586 do_sys_openat2+0x16d/0x4d0 fs/open.c:1212 do_sys_open fs/open.c:1228 [inline] __do_sys_open fs/open.c:1236 [inline] __se_sys_open fs/open.c:1232 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1232 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f13217d6840 RSP: 002b:00007fff26d02cd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007fff26d02dd0 RCX: 00007f13217d6840 RDX: 000056249019ffe3 RSI: 00000000000a0800 RDI: 00005624905646a0 RBP: 0000000000000000 R08: 000056249019f670 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff26d02e80 R13: 0000562490545010 R14: 0000562490553d30 R15: 00007fff26d02d50 INFO: task syz-executor.5:11388 blocked for more than 143 seconds. Not tainted 5.16.0-rc1-next-20211118-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:23504 pid:11388 ppid: 1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4987 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6268 schedule+0xd2/0x260 kernel/sched/core.c:6341 blk_mq_freeze_queue_wait+0x112/0x160 block/blk-mq.c:178 __loop_clr_fd+0x1ae/0x1070 drivers/block/loop.c:1122 lo_release+0x1ac/0x1f0 drivers/block/loop.c:1761 blkdev_put_whole block/bdev.c:694 [inline] blkdev_put+0x2fb/0x9e0 block/bdev.c:956 deactivate_locked_super+0x94/0x160 fs/super.c:335 deactivate_super+0xad/0xd0 fs/super.c:366 cleanup_mnt+0x3a2/0x540 fs/namespace.c:1137 task_work_run+0xdd/0x1a0 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+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fa95c908f57 RSP: 002b:00007fff308781e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fa95c908f57 RDX: 00007fff308782ba RSI: 000000000000000a RDI: 00007fff308782b0 RBP: 00007fff308782b0 R08: 00000000ffffffff R09: 00007fff30878080 R10: 0000555555865873 R11: 0000000000000246 R12: 00007fa95c961105 R13: 00007fff30879370 R14: 0000555555865810 R15: 00007fff308793b0 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8bb83ba0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458 5 locks held by kworker/u4:2/44: 1 lock held by systemd-udevd/2973: #0: ffff88801a555918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev.part.0+0x9b/0xb50 block/bdev.c:819 1 lock held by in:imklog/6409: #0: ffff88801db05270 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 2 locks held by kworker/u4:19/9042: #0: ffff8880b9c39a98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:478 #1: ffff8880b9c279c8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x173/0x490 kernel/sched/psi.c:871 2 locks held by syz-executor.5/11388: #0: ffff88801a555918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x97/0x9e0 block/bdev.c:914 #1: ffff88801a551360 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x7a/0x1070 drivers/block/loop.c:1106 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.16.0-rc1-next-20211118-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+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:254 [inline] watchdog+0xcb7/0xed0 kernel/hung_task.c:339 kthread+0x405/0x4f0 kernel/kthread.c:327 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: 2969 Comm: systemd-journal Not tainted 5.16.0-rc1-next-20211118-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:88 [inline] RIP: 0010:lock_is_held_type+0x29/0x140 kernel/locking/lockdep.c:5673 Code: 00 41 57 41 56 41 55 41 bd ff ff ff ff 41 54 55 53 48 83 ec 08 8b 0d 82 e3 4f 04 85 c9 0f 84 d9 00 00 00 65 8b 05 e7 41 c1 76 <85> c0 0f 85 ca 00 00 00 65 4c 8b 24 25 40 70 02 00 41 8b 94 24 64 RSP: 0018:ffffc9000275fce0 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 1ffff920004ebfa8 RCX: 0000000000000001 RDX: 1ffffffff177192e RSI: 00000000ffffffff RDI: ffffffff8bb83ae0 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8d90e7d7 R10: fffffbfff1b21cfa R11: 0000000000000000 R12: 0000000000000001 R13: 00000000ffffffff R14: ffffffff8bb83ba0 R15: 0000000000000000 FS: 00007f7d06fc98c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7d044d8000 CR3: 0000000019bed000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:283 [inline] rcu_read_lock_sched_held+0x3a/0x70 kernel/rcu/update.c:125 trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0x442/0x510 kernel/locking/lockdep.c:5608 rcu_lock_acquire include/linux/rcupdate.h:268 [inline] rcu_read_lock include/linux/rcupdate.h:688 [inline] dput+0x77/0xbc0 fs/dcache.c:874 path_put+0x2d/0x60 fs/namei.c:557 do_faccessat+0x339/0x850 fs/open.c:455 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f7d062849c7 Code: 83 c4 08 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d c8 d4 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 15 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 d4 2b 00 f7 d8 64 89 01 48 RSP: 002b:00007ffc70bbc578 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 00007ffc70bbf490 RCX: 00007f7d062849c7 RDX: 00007f7d06cf5a00 RSI: 0000000000000000 RDI: 00005633595db9a3 RBP: 00007ffc70bbc5b0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ffc70bbf490 R15: 00007ffc70bbcaa0 ---------------- Code disassembly (best guess): 0: 00 41 57 add %al,0x57(%rcx) 3: 41 56 push %r14 5: 41 55 push %r13 7: 41 bd ff ff ff ff mov $0xffffffff,%r13d d: 41 54 push %r12 f: 55 push %rbp 10: 53 push %rbx 11: 48 83 ec 08 sub $0x8,%rsp 15: 8b 0d 82 e3 4f 04 mov 0x44fe382(%rip),%ecx # 0x44fe39d 1b: 85 c9 test %ecx,%ecx 1d: 0f 84 d9 00 00 00 je 0xfc 23: 65 8b 05 e7 41 c1 76 mov %gs:0x76c141e7(%rip),%eax # 0x76c14211 * 2a: 85 c0 test %eax,%eax <-- trapping instruction 2c: 0f 85 ca 00 00 00 jne 0xfc 32: 65 4c 8b 24 25 40 70 mov %gs:0x27040,%r12 39: 02 00 3b: 41 rex.B 3c: 8b .byte 0x8b 3d: 94 xchg %eax,%esp 3e: 24 64 and $0x64,%al