INFO: task syz.0.507:8310 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.507 state:D stack:26440 pid:8310 ppid:5770 flags:0x00004004 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 blkdev_get_by_dev+0x121/0x600 block/bdev.c:805 bdev_open_by_dev+0x77/0x100 block/bdev.c:859 setup_bdev_super+0x59/0x660 fs/super.c:1496 get_tree_bdev+0x346/0x520 fs/super.c:1588 vfs_get_tree+0x8c/0x280 fs/super.c:1764 do_new_mount+0x24b/0xa40 fs/namespace.c:3386 do_mount fs/namespace.c:3726 [inline] __do_sys_mount fs/namespace.c:3935 [inline] __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912 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: 0033:0x7fb8b559bf79 RSP: 002b:00007fb8b64f4028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fb8b5816180 RCX: 00007fb8b559bf79 RDX: 0000200000000000 RSI: 0000200000000040 RDI: 00002000000000c0 RBP: 00007fb8b56327e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb8b5816218 R14: 00007fb8b5816180 R15: 00007ffee320a438 Showing all locks held in the system: 2 locks held by kworker/1:0/23: #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711 #1: ffff8880b8f289c0 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline] #1: ffff8880b8f289c0 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2176/0x45a0 kernel/sched/core.c:6695 1 lock held by khungtaskd/28: #0: ffffffff8d131fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8d131fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8d131fa0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 3 locks held by kworker/u4:5/60: 2 locks held by getty/5523: #0: ffff88823bc140a0 (&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 1 lock held by syz-executor/5773: 1 lock held by syz-executor/6943: 1 lock held by udevd/7006: #0: ffff8881413bd4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805 1 lock held by syz.0.507/8310: #0: ffff8881413bd4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 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: 6943 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:memset+0x4/0x20 arch/x86/lib/memset_64.S:32 Code: 66 44 8b 54 16 fe 66 44 89 1f 66 44 89 54 17 fe eb 0c 48 83 fa 01 72 06 44 8a 1e 44 88 1f c3 cc cc cc cc cc cc cc f3 0f 1e fa 1a 49 89 f9 40 88 f0 48 89 d1 f3 aa 4c 89 c8 c3 90 90 90 90 90 RSP: 0018:ffffc90003157310 EFLAGS: 00000202 RAX: ffffc90003157701 RBX: ffffc90003157420 RCX: ffffffff813b4c68 RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc90003157438 RBP: ffffc90003157438 R08: ffffc90003157447 R09: 1ffff9200062ae88 R10: dffffc0000000000 R11: fffff5200062ae89 R12: ffffc900031573e8 R13: dffffc0000000000 R14: ffffffff81d3043e R15: ffffffff8f189932 FS: 0000555567c48500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055ea78568660 CR3: 0000000067ce1000 CR4: 00000000003506f0 Call Trace: unwind_next_frame+0x1648/0x2970 arch/x86/kernel/unwind_orc.c:592 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 save_stack+0x125/0x230 mm/page_owner.c:128 __reset_page_owner+0x4e/0x190 mm/page_owner.c:149 reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page_list+0xbe/0x860 mm/page_alloc.c:2504 release_pages+0x1f7a/0x2200 mm/swap.c:1022 __folio_batch_release+0x71/0xe0 mm/swap.c:1042 folio_batch_release include/linux/pagevec.h:83 [inline] shmem_undo_range+0x630/0x1b20 mm/shmem.c:1026 shmem_truncate_range mm/shmem.c:1135 [inline] shmem_evict_inode+0x245/0x9e0 mm/shmem.c:1264 evict+0x4ca/0x8d0 fs/inode.c:705 do_unlinkat+0x38c/0x590 fs/namei.c:4406 __do_sys_unlink fs/namei.c:4447 [inline] __se_sys_unlink fs/namei.c:4445 [inline] __x64_sys_unlink+0x49/0x50 fs/namei.c:4445 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: 0033:0x7f7a9c39b067 Code: 73 01 c3 48 c7 c1 e8 ff ff ff 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 57 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffd4e871448 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7a9c39b067 RDX: 00007ffd4e871470 RSI: 00007ffd4e871500 RDI: 00007ffd4e871500 RBP: 00007ffd4e871500 R08: 00007ffd4e872500 R09: 00000000ffffffff R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffd4e872590 R13: 00007f7a9c431c3b R14: 000000000009cd59 R15: 00007ffd4e8725d0