INFO: task syz-executor407:5839 blocked for more than 143 seconds. Not tainted 6.14.0-rc7-syzkaller-00074-ga7f2e10ecd8f #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor407 state:D stack:27056 pid:5839 tgid:5838 ppid:5834 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x6bd/0xb10 kernel/locking/mutex.c:730 bdev_release+0x15a/0x6d0 block/bdev.c:1086 blkdev_release+0x15/0x20 block/fops.c:660 __fput+0x3ff/0xb70 fs/file_table.c:464 task_work_run+0x14e/0x250 kernel/task_work.c:227 ptrace_notify+0x10e/0x130 kernel/signal.c:2522 ptrace_report_syscall include/linux/ptrace.h:415 [inline] ptrace_report_syscall_exit include/linux/ptrace.h:477 [inline] syscall_exit_work kernel/entry/common.c:173 [inline] syscall_exit_to_user_mode_prepare+0x126/0x290 kernel/entry/common.c:200 __syscall_exit_to_user_mode_work kernel/entry/common.c:205 [inline] syscall_exit_to_user_mode+0x11/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd8d462c839 RSP: 002b:00007fd8d45e4218 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 00007fd8d46b4328 RCX: 00007fd8d462c839 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 00007fd8d46b4320 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd8d46b432c R13: 00007fd8d468135c R14: 64626e2f7665642f R15: 0000400000000000 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746 2 locks held by getty/5570: #0: ffff8880364aa0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900033332f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 1 lock held by udevd/5835: #0: ffff888025bca4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe20 block/bdev.c:903 1 lock held by syz-executor407/5839: #0: ffff888025bca4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x15a/0x6d0 block/bdev.c:1086 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-rc7-syzkaller-00074-ga7f2e10ecd8f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 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:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0xf62/0x12b0 kernel/hung_task.c:399 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111