INFO: task syz-executor.0:5164 blocked for more than 143 seconds. Not tainted 6.8.0-rc4-syzkaller-g7e90b5c295ec #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:29040 pid:5164 tgid:5163 ppid:5139 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0xf12/0x5c60 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0xe9/0x280 kernel/sched/core.c:6817 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6874 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5bd/0x9d0 kernel/locking/mutex.c:752 bdev_release+0xcd/0xa80 block/bdev.c:969 blkdev_release+0x37/0x50 block/fops.c:631 __fput+0x270/0xb80 fs/file_table.c:376 task_work_run+0x14f/0x250 kernel/task_work.c:180 get_signal+0x1073/0x2790 kernel/signal.c:2669 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:105 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0x156/0x2b0 kernel/entry/common.c:212 do_syscall_64+0xe5/0x270 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x4546c9 RSP: 002b:00007f0baef940f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 00000000004546c9 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 0000000000000409 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004e3e00 R13: 00007f0baef94674 R14: 000000000054bf00 R15: 00000000004f4040 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d7ad160 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8d7ad160 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8d7ad160 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6614 2 locks held by getty/4813: #0: ffff88802a90b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900015d02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfca/0x1490 drivers/tty/n_tty.c:2201 1 lock held by udevd/5126: #0: ffff8880206a44c8 (&disk->open_mutex){+.+.}-{3:3}, at: bdev_open_by_dev+0x276/0xec0 block/bdev.c:859 1 lock held by syz-executor.0/5164: #0: ffff8880206a44c8 (&disk->open_mutex){+.+.}-{3:3}, at: bdev_release+0xcd/0xa80 block/bdev.c:969 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc4-syzkaller-g7e90b5c295ec #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+0xd9/0x1b0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf87/0x1210 kernel/hung_task.c:379 kthread+0x2c6/0x3b0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4498 Comm: klogd Not tainted 6.8.0-rc4-syzkaller-g7e90b5c295ec #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 RIP: 0010:__sanitizer_cov_trace_switch+0x40/0x90 kernel/kcov.c:341 Code: 48 83 f8 20 74 6b 77 48 48 83 f8 08 74 5b 48 83 f8 10 75 2f 41 bd 03 00 00 00 4c 8b 75 00 31 db 4d 85 f6 74 1e 48 8b 74 dd 10 <4c> 89 e2 4c 89 ef 48 83 c3 01 48 8b 4c 24 28 e8 8c fd ff ff 49 39 RSP: 0018:ffffc90003477898 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 0000000000000008 RCX: ffffffff8ab6756a RDX: ffff88807eba8000 RSI: 0000000000000011 RDI: 0000000000000001 RBP: ffffffff8c5c02a0 R08: 0000000000000001 R09: 0000000000000010 R10: 000000000000000f R11: fffffffffffe3968 R12: 000000000000000f R13: 0000000000000001 R14: 000000000000000a R15: 000000000000000f FS: 00007f515f5c7380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055f7b9a9b680 CR3: 000000002fab0000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vsnprintf+0x7ba/0x1870 lib/vsprintf.c:2793 snprintf+0xc8/0x100 lib/vsprintf.c:2959 print_caller kernel/printk/printk.c:1333 [inline] info_print_prefix+0x135/0x350 kernel/printk/printk.c:1352 record_print_text+0x143/0x410 kernel/printk/printk.c:1399 syslog_print+0x4e9/0x5d0 kernel/printk/printk.c:1610 do_syslog+0x2d8/0x580 kernel/printk/printk.c:1728 __do_sys_syslog kernel/printk/printk.c:1820 [inline] __se_sys_syslog kernel/printk/printk.c:1818 [inline] __x64_sys_syslog+0x74/0xb0 kernel/printk/printk.c:1818 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd5/0x270 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f515f728fa7 Code: 73 01 c3 48 8b 0d 81 ce 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 67 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 51 ce 0c 00 f7 d8 64 89 01 48 RSP: 002b:00007ffea3471978 EFLAGS: 00000206 ORIG_RAX: 0000000000000067 RAX: ffffffffffffffda RBX: 00007f515f8c74a0 RCX: 00007f515f728fa7 RDX: 00000000000003ff RSI: 00007f515f8c74a0 RDI: 0000000000000002 RBP: 0000000000000000 R08: 0000000000000007 R09: 277d4c939d8b5048 R10: 0000000000004000 R11: 0000000000000206 R12: 00007f515f8c74a0 R13: 00007f515f8b7212 R14: 00007f515f8c7535 R15: 00007f515f8c7535