INFO: task syz.5.651:9230 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.651 state:D stack:23528 pid:9230 ppid:6496 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6a9/0xcc0 kernel/locking/mutex.c:747 sync_bdevs+0x1af/0x330 block/bdev.c:1076 ksys_sync+0xc6/0x170 fs/sync.c:105 __ia32_sys_sync+0xe/0x20 fs/sync.c:113 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f5c85b9bf79 RSP: 002b:00007f5c86b2a028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f5c85e15fa0 RCX: 00007f5c85b9bf79 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f5c85e15fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5c85e16038 R14: 00007f5c85e15fa0 R15: 00007ffe7ffe43e8 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d131fe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8d131fe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8d131fe0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by getty/5530: #0: ffff8880312c20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x433/0x1390 drivers/tty/n_tty.c:2217 2 locks held by syz-executor/5768: 1 lock held by udevd/7716: #0: ffff8881417b94c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805 1 lock held by udevd/7922: #0: ffff8881417784c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805 1 lock held by syz.5.651/9230: #0: ffff8881417784c8 (&disk->open_mutex){+.+.}-{3:3}, at: sync_bdevs+0x1af/0x330 block/bdev.c:1076 1 lock held by syz-executor/9875: #0: ffffffff8d1379b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline] #0: ffffffff8d1379b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x306/0x880 kernel/rcu/tree_exp.h:1004 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 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+0xf3d/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 8142 Comm: udevd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:mark_lock+0x101/0x320 kernel/locking/lockdep.c:4697 Code: 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 e4 5c 76 00 b8 01 00 00 00 45 85 27 74 50 48 83 c4 08 5b 41 5c 41 5d 41 5e <41> 5f 5d c3 e8 86 12 bd 02 85 c0 74 c1 48 c7 c0 f0 11 8b 8e 48 c1 RSP: 0018:ffffc9000543f668 EFLAGS: 00000086 RAX: 0000000000000001 RBX: ffff88802b9046d8 RCX: ffffffff8168e064 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff911bf5a8 RBP: 0000000000000002 R08: ffffffff911bf5af R09: 1ffffffff2237eb5 R10: dffffc0000000000 R11: fffffbfff2237eb6 R12: ffff88802b904728 R13: 0000000000000001 R14: 1ffff110057208db R15: ffffffff90b6bc30 FS: 00007f798638f880(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f22b07e6ad8 CR3: 0000000061c1e000 CR4: 00000000003506f0 Call Trace: mark_held_locks kernel/locking/lockdep.c:4274 [inline] __trace_hardirqs_on_caller kernel/locking/lockdep.c:4292 [inline] lockdep_hardirqs_on_prepare+0x24d/0x770 kernel/locking/lockdep.c:4359 trace_hardirqs_on+0x28/0x40 kernel/trace/trace_preemptirq.c:61 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] _raw_spin_unlock_irqrestore+0x86/0x120 kernel/locking/spinlock.c:194 __debug_check_no_obj_freed lib/debugobjects.c:999 [inline] debug_check_no_obj_freed+0x51f/0x540 lib/debugobjects.c:1020 slab_free_hook mm/slub.c:1786 [inline] slab_free_freelist_hook+0xd2/0x1a0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] __kmem_cache_free+0xba/0x1e0 mm/slub.c:3843 tomoyo_realpath_from_path+0x59d/0x5d0 security/tomoyo/realpath.c:286 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path2_perm+0x2e9/0x740 security/tomoyo/file.c:923 tomoyo_path_rename+0x14f/0x1a0 security/tomoyo/tomoyo.c:299 security_path_rename+0x16c/0x200 security/security.c:1828 do_renameat2+0x6be/0xce0 fs/namei.c:5020 __do_sys_rename fs/namei.c:5079 [inline] __se_sys_rename fs/namei.c:5077 [inline] __x64_sys_rename+0x86/0x90 fs/namei.c:5077 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f7985c7acc7 Code: e8 5e a7 09 00 f7 d8 19 c0 5b c3 0f 1f 84 00 00 00 00 00 b8 ff ff ff ff 5b c3 66 0f 1f 84 00 00 00 00 00 b8 52 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 8b 15 01 61 17 00 f7 d8 64 89 02 b8 RSP: 002b:00007ffd78c3d7b8 EFLAGS: 00000202 ORIG_RAX: 0000000000000052 RAX: ffffffffffffffda RBX: 000055714db708a0 RCX: 00007f7985c7acc7 RDX: 000055714db49010 RSI: 00007ffd78c3d7d0 RDI: 00007ffd78c3dbd0 RBP: 000055714db61e00 R08: 00000000000001e0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffd78c3d7d0 R13: 00007ffd78c3dbd0 R14: 0000000000000000 R15: 000055712be229dd