INFO: task syz-executor:5835 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 state:D stack:21096 pid:5835 tgid:5835 ppid:1 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 __bch2_fs_stop+0x704/0x900 fs/bcachefs/super.c:696 generic_shutdown_super+0x132/0x2c0 fs/super.c:643 bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2618 deactivate_locked_super+0xbc/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1375 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f66ef7801f7 RSP: 002b:00007ffe89e0dcf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f66ef7801f7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe89e0ddb0 RBP: 00007ffe89e0ddb0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe89e0ee40 R13: 00007f66ef801d7d R14: 000000000002a2d8 R15: 00007ffe89e0ee80 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/u8:2/43: #0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90000b47bc0 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90000b47bc0 ((reaper_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 4 locks held by kworker/u8:8/1124: 2 locks held by getty/5590: #0: ffff88823bf600a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5835: #0: ffff8880377980d0 (&type->s_umount_key#107){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff8880377980d0 (&type->s_umount_key#107){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff8880377980d0 (&type->s_umount_key#107){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 3 locks held by kworker/0:4/5913: 2 locks held by udevd/5963: 2 locks held by udevd/6275: 1 lock held by udevd/6286: 2 locks held by kworker/u8:12/6348: #0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90005e0fbc0 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90005e0fbc0 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 6 locks held by syz.7.352/8238: 2 locks held by syz.7.352/8277: 3 locks held by syz.5.353/8242: #0: ffff8880314a4488 (sb_writers#16){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3108 [inline] #0: ffff8880314a4488 (sb_writers#16){.+.+}-{0:0}, at: vfs_fallocate+0x5f9/0x7f0 fs/open.c:341 #1: ffff888065634790 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: xfs_ilock+0xfe/0x390 fs/xfs/xfs_inode.c:149 #2: ffff888065634960 (mapping.invalidate_lock#3){++++}-{4:4}, at: xfs_ilock+0x17d/0x390 fs/xfs/xfs_inode.c:157 1 lock held by syz.1.354/8244: 2 locks held by syz.6.356/8276: #0: ffffffff8e0b0b70 (tomoyo_ss){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #0: ffffffff8e0b0b70 (tomoyo_ss){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #0: ffffffff8e0b0b70 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_read_lock security/tomoyo/common.h:1108 [inline] #0: ffffffff8e0b0b70 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_path_number_perm+0x1bc/0x5a0 security/tomoyo/file.c:722 #1: ffff888019840d58 (&n->list_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline] #1: ffff888019840d58 (&n->list_lock){+.+.}-{3:3}, at: get_partial_node+0x3a/0x3a0 mm/slub.c:2904 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(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:328 [inline] watchdog+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x436/0x7d0 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: 8241 Comm: syz.5.353 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:36 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:139 [inline] RIP: 0010:wrmsrq arch/x86/include/asm/msr.h:199 [inline] RIP: 0010:native_apic_msr_write+0x39/0x50 arch/x86/include/asm/apic.h:212 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 e9 40 5f 89 09 cc f3 0f 1e fa 89 f6 31 d2 e9 b2 9c 7e 03 66 RSP: 0018:ffffc90005c4fad8 EFLAGS: 00000046 RAX: 000000000000ffd9 RBX: ffff8880b8823900 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 000000000000ffd9 RDI: 0000000000000838 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: ffffffff81703470 R12: 0000000010000bbe R13: dffffc0000000000 R14: 000000000000ffd9 R15: 0000000000000020 FS: 000055557152f500(0000) GS:ffff8881268bc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007faeee547000 CR3: 000000003bafc000 CR4: 00000000003526f0 Call Trace: apic_write arch/x86/include/asm/apic.h:405 [inline] lapic_next_event+0x11/0x20 arch/x86/kernel/apic/apic.c:416 clockevents_program_event+0x1cc/0x360 kernel/time/clockevents.c:334 hrtimer_start_range_ns+0xdc9/0x10a0 kernel/time/hrtimer.c:1330 hrtimer_start_expires include/linux/hrtimer.h:277 [inline] hrtimer_sleeper_start_expires kernel/time/hrtimer.c:2023 [inline] do_nanosleep+0x1e1/0x640 kernel/time/hrtimer.c:2097 hrtimer_nanosleep+0x1f7/0x410 kernel/time/hrtimer.c:2147 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1399 [inline] __se_sys_clock_nanosleep+0x2f1/0x380 kernel/time/posix-timers.c:1376 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: 0033:0x7fede7731785 Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 f6 54 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 4f 55 ff ff 48 8b 04 24 48 83 c4 28 f7 d8 RSP: 002b:00007ffd65025290 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 00007fede7955fa0 RCX: 00007fede7731785 RDX: 00007ffd650252d0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fede7957da0 R08: 0000000000000000 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000293 R12: 00000000000524a8 R13: 00007ffd650253f0 R14: ffffffffffffffff R15: 00007ffd65025410