INFO: task syz-executor.4:18914 blocked for more than 143 seconds. Not tainted 6.1.77-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:23640 pid:18914 ppid:3580 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747 blkdev_put+0x100/0x750 block/bdev.c:913 blkdev_close+0x56/0x80 block/fops.c:514 __fput+0x3b7/0x890 fs/file_table.c:320 task_work_run+0x246/0x300 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:171 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:297 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fdc1107cc9a RSP: 002b:00007ffcf3b601d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000006 RCX: 00007fdc1107cc9a RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 00007fdc111ad980 R08: 0000001b33620000 R09: 0000000000000151 R10: 00000000818e34c2 R11: 0000000000000293 R12: 00000000001ebfdc R13: ffffffffffffffff R14: 00007fdc10c00000 R15: 00000000001ebc9b Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d12a910 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d12b110 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by khungtaskd/28: #0: ffffffff8d12a740 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:318 [inline] #0: ffffffff8d12a740 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:759 [inline] #0: ffffffff8d12a740 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494 1 lock held by syslogd/2985: #0: ffff8880b9839e18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 2 locks held by getty/3305: #0: ffff8880288b3098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2188 1 lock held by udevd/30672: #0: ffff8880202bb4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x148/0xa10 block/bdev.c:815 1 lock held by udevd/4809: #0: ffff888143f0d4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x148/0xa10 block/bdev.c:815 1 lock held by syz-executor.4/18914: #0: ffff8880202bb4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x100/0x750 block/bdev.c:913 1 lock held by syz-executor.4/19256: #0: ffff8880202bb4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x148/0xa10 block/bdev.c:815 1 lock held by syz-executor.0/19346: #0: ffff888143f0d4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x100/0x750 block/bdev.c:913 1 lock held by syz-executor.4/19471: #0: ffff8880202bb4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x148/0xa10 block/bdev.c:815 1 lock held by syz-executor.4/19796: #0: ffff8880202bb4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x148/0xa10 block/bdev.c:815 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.77-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2985 Comm: syslogd Not tainted 6.1.77-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 RIP: 0010:__skb_datagram_iter+0x0/0x780 net/core/datagram.c:410 Code: 41 b8 01 00 00 00 49 c7 c1 e0 5e 36 84 41 56 e8 16 00 00 00 48 83 c4 08 5b 41 5c 41 5e 41 5f 5d c3 66 0f 1f 84 00 00 00 00 00 <55> 41 57 41 56 41 55 41 54 53 48 83 ec 60 4c 89 4c 24 30 45 89 c7 RSP: 0018:ffffc900030ef958 EFLAGS: 00000246 RAX: ffffffff887c040d RBX: 0000000000000001 RCX: 000000000000005d RDX: ffffc900030efbd0 RSI: 0000000000000000 RDI: ffff8880a49b1dc0 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff887c0600 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880a49b1dc0 R13: 0000000000000000 R14: 000000000000005d R15: ffffc900030efbd0 FS: 00007f65db876380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c01f00d770 CR3: 000000007ec64000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: skb_copy_datagram_iter+0xe1/0x2b0 net/core/datagram.c:527 skb_copy_datagram_msg include/linux/skbuff.h:3924 [inline] __unix_dgram_recvmsg+0x7e3/0x1260 net/unix/af_unix.c:2485 sock_recvmsg_nosec net/socket.c:1022 [inline] sock_recvmsg net/socket.c:1040 [inline] sock_read_iter+0x3b2/0x4b0 net/socket.c:1121 call_read_iter include/linux/fs.h:2243 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x7de/0xbe0 fs/read_write.c:470 ksys_read+0x19c/0x2c0 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f65db9cab6a Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffc54fe3df8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f65db9cab6a RDX: 00000000000000ff RSI: 000055c409dd7950 RDI: 0000000000000000 RBP: 000055c409dd7910 R08: 0000000000000001 R09: 0000000000000000 R10: 00007f65dbb693a3 R11: 0000000000000246 R12: 000055c409dd79a3 R13: 000055c409dd7950 R14: 0000000000000000 R15: 00007f65dbba7a80