INFO: task syz-executor.0:6117 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:25608 pid:6117 tgid:6117 ppid:6026 task_flags:0x400040 flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 bdev_release+0x1a9/0x650 block/bdev.c:1128 blkdev_release+0x15/0x20 block/fops.c:702 __fput+0x44c/0xa70 fs/file_table.c:468 fput_close_sync+0x119/0x200 fs/file_table.c:573 __do_sys_close fs/open.c:1587 [inline] __se_sys_close fs/open.c:1572 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1572 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff6fa27b8da RSP: 002b:00007ffcbc923090 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 00007ff6fa27b8da RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 00007ff6fa39d980 R08: 0000001b2c560000 R09: 7fffffffffffffff R10: 3fffffffffffffff R11: 0000000000000293 R12: 000000000001ae0a R13: ffffffffffffffff R14: 00007ff6f9e00000 R15: 000000000001aac9 INFO: task syz-executor.0:6123 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:28536 pid:6123 tgid:6117 ppid:6026 task_flags:0x400140 flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 bdev_open+0xe0/0xd30 block/bdev.c:945 bdev_file_open_by_dev+0x1be/0x240 block/bdev.c:1059 disk_scan_partitions+0x1c1/0x2c0 block/genhd.c:387 blkdev_common_ioctl+0x1686/0x2550 block/ioctl.c:625 blkdev_ioctl+0x4f6/0x6d0 block/ioctl.c:699 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff6fa27c8d9 RSP: 002b:00007ff6faffb0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ff6fa39c050 RCX: 00007ff6fa27c8d9 RDX: 0000000000000000 RSI: 000000000000125f RDI: 0000000000000003 RBP: 00007ff6fa2d8ad0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007ff6fa39c050 R15: 00007ffcbc922fc8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8dd3b160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8dd3b160 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8dd3b160 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5587: #0: ffff888032f910a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by udevd/6011: #0: ffff888024af8358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 1 lock held by syz-executor.0/6117: #0: ffff888024af8358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x1a9/0x650 block/bdev.c:1128 1 lock held by syz-executor.0/6123: #0: ffff888024af8358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 1 lock held by syz-executor.0/6250: #0: ffff888024af8358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 1 lock held by syz-executor.0/6251: #0: ffff888024af8358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 1 lock held by syz-executor.0/6281: #0: ffff888024af8358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 1 lock held by syz-executor.0/6282: #0: ffff888024af8358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:trace_softirq_raise+0x45/0x110 include/trace/events/irq.h:156 Code: 91 5b 8f be 08 00 00 00 e8 48 82 a0 00 48 0f a3 1d 60 f1 d7 0d 73 12 e8 99 7a 21 00 84 c0 75 09 80 3d 0a ed c1 0d 00 74 0f 5b <41> 5e e9 1f a1 8c ff cc 90 0f 0b 90 eb be c6 05 f2 ec c1 0d 01 90 RSP: 0018:ffffc90000007f48 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000000007 RCX: 783b66ed507c0100 RDX: 0000000000000000 RSI: ffffffff8b9ec340 RDI: ffffffff8b9ec300 RBP: 0000000000000000 R08: ffffffff8f5b9137 R09: 1ffffffff1eb7226 R10: dffffc0000000000 R11: fffffbfff1eb7227 R12: 1ffff1101710740d R13: ffff8880b883a068 R14: ffff8880b883a060 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888126396000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000556d7542a168 CR3: 000000000db36000 CR4: 0000000000350ef0 Call Trace: __raise_softirq_irqoff+0x4c/0xc0 kernel/softirq.c:789 csd_do_func kernel/smp.c:136 [inline] __flush_smp_call_function_queue+0x6e6/0xaa0 kernel/smp.c:577 __sysvec_call_function_single+0xa8/0x3d0 arch/x86/kernel/smp.c:271 instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline] sysvec_call_function_single+0x9e/0xc0 arch/x86/kernel/smp.c:266 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: 9e 37 dd f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d f3 1a 15 00 f3 0f 1e fa fb f4 73 37 dd f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffffff8da07d80 EFLAGS: 000002c2 RAX: 783b66ed507c0100 RBX: ffffffff81954a27 RCX: 783b66ed507c0100 RDX: 0000000000000001 RSI: ffffffff8d50db0d RDI: ffffffff8b9ec360 RBP: ffffffff8da07eb8 R08: ffff8880b8832fdb R09: 1ffff110171065fb R10: dffffc0000000000 R11: ffffed10171065fc R12: ffffffff8f5b9130 R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1b52a40 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x1e7/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428 rest_init+0x2de/0x300 init/main.c:757 start_kernel+0x3ae/0x410 init/main.c:1111 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x147