INFO: task syz-executor.4:8232 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.4 state:D stack:23696 pid: 8232 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: 0033:0x7f900fd23f57 RSP: 002b:00007ffd07797528 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f900fd23f57 RDX: 00007ffd077975fa RSI: 000000000000000a RDI: 00007ffd077975f0 RBP: 00007ffd077975f0 R08: 00000000ffffffff R09: 00007ffd077973c0 R10: 0000555555be4903 R11: 0000000000000246 R12: 00007f900fd7c105 R13: 00007ffd077986b0 R14: 0000555555be4810 R15: 00007ffd077986f0 INFO: task systemd-udevd:10618 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:26856 pid:10618 ppid: 2973 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: 0033:0x7fe53e66c840 RSP: 002b:00007ffee5211388 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000055f9875763c0 RCX: 00007fe53e66c840 RDX: 000055f985d5ffe3 RSI: 00000000000a0800 RDI: 000055f987575070 RBP: 00007ffee5211500 R08: 000055f985d5f670 R09: 0000000000000010 R10: 000055f985d5fd0c R11: 0000000000000246 R12: 00007ffee5211450 R13: 000055f9875637c0 R14: 0000000000000003 R15: 000000000000000e 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 1 lock held by in:imklog/6222: #0: ffff88807a0fd9f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 2 locks held by syz-executor.4/8232: #0: ffff88801ac30918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x97/0x9e0 block/bdev.c:914 #1: ffff88801abfcb60 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x7a/0x1070 drivers/block/loop.c:1106 1 lock held by systemd-udevd/10618: #0: ffff88801ac30918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev.part.0+0x9b/0xb50 block/bdev.c:819 ============================================= 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: 2963 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:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:132 [inline] RIP: 0010:lock_is_held_type+0xea/0x140 kernel/locking/lockdep.c:5682 Code: c0 45 31 ed 44 39 f0 41 0f 94 c5 48 c7 c7 80 10 ac 89 e8 a9 0d 00 00 b8 ff ff ff ff 65 0f c1 05 2c 41 c1 76 83 f8 01 75 29 9c <58> f6 c4 02 75 3d 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 44 RSP: 0018:ffffc90001f4fdd8 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffffff8bb83ae0 R08: 0000000000000000 R09: ffffffff8d90e7d7 R10: fffffbfff1b21cfa R11: 0000000000000001 R12: ffff88807a300000 R13: 0000000000000000 R14: 00000000ffffffff R15: ffff88807a300a68 FS: 00007fcae8ea48c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcae6325000 CR3: 0000000079f47000 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_release include/trace/events/lock.h:58 [inline] lock_release+0x522/0x720 kernel/locking/lockdep.c:5648 do_write_seqcount_end include/linux/seqlock.h:565 [inline] vtime_user_enter+0xea/0x170 kernel/sched/cputime.c:712 __context_tracking_enter+0xef/0x100 kernel/context_tracking.c:82 user_enter_irqoff include/linux/context_tracking.h:41 [inline] __exit_to_user_mode kernel/entry/common.c:130 [inline] syscall_exit_to_user_mode+0x48/0x60 kernel/entry/common.c:302 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fcae815f9c7 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:00007ffc6d0a40d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: 0000000000000000 RBX: 00007ffc6d0a7100 RCX: 00007fcae815f9c7 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00005617d25489a3 RBP: 00007ffc6d0a4220 R08: 00005617d253e3e5 R09: 0000000000000018 R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00005617d3d798a0 R15: 00007ffc6d0a4710 ---------------- Code disassembly (best guess): 0: c0 45 31 ed rolb $0xed,0x31(%rbp) 4: 44 39 f0 cmp %r14d,%eax 7: 41 0f 94 c5 sete %r13b b: 48 c7 c7 80 10 ac 89 mov $0xffffffff89ac1080,%rdi 12: e8 a9 0d 00 00 callq 0xdc0 17: b8 ff ff ff ff mov $0xffffffff,%eax 1c: 65 0f c1 05 2c 41 c1 xadd %eax,%gs:0x76c1412c(%rip) # 0x76c14150 23: 76 24: 83 f8 01 cmp $0x1,%eax 27: 75 29 jne 0x52 29: 9c pushfq * 2a: 58 pop %rax <-- trapping instruction 2b: f6 c4 02 test $0x2,%ah 2e: 75 3d jne 0x6d 30: 48 f7 04 24 00 02 00 testq $0x200,(%rsp) 37: 00 38: 74 01 je 0x3b 3a: fb sti 3b: 48 83 c4 08 add $0x8,%rsp 3f: 44 rex.R