INFO: task syz.3.1506:11774 blocked for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1506 state:D stack:26424 pid:11774 tgid:11769 ppid:5801 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7004
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
bdev_open+0xa2/0xe40 block/bdev.c:961
bdev_file_open_by_dev block/bdev.c:1075 [inline]
bdev_file_open_by_dev+0x179/0x210 block/bdev.c:1050
setup_bdev_super+0x385/0x730 fs/super.c:1612
get_tree_bdev_flags+0x363/0x620 fs/super.c:1692
vfs_get_tree+0x92/0x320 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3760 [inline]
do_new_mount fs/namespace.c:3836 [inline]
path_mount+0x7d0/0x23d0 fs/namespace.c:4146
do_mount fs/namespace.c:4159 [inline]
__do_sys_mount fs/namespace.c:4348 [inline]
__se_sys_mount fs/namespace.c:4325 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4325
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb25d79bf79
RSP: 002b:00007fb25e680028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fb25da16180 RCX: 00007fb25d79bf79
RDX: 0000200000000100 RSI: 0000200000000000 RDI: 0000200000000080
RBP: 00007fb25d8327e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000200000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb25da16218 R14: 00007fb25da16180 R15: 00007fffb7b32af8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e7e94a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7e94a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7e94a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by getty/5562:
#0: ffff888038c890a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
3 locks held by kworker/0:5/5871:
#0: ffff88813fe63548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
#1: ffffc900043afd08 (key_gc_work){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
#2: ffffffff8e7f50b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311
1 lock held by udevd/5953:
#0: ffff888028129358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:961
2 locks held by syz.3.1506/11774:
#0: ffff8880277e40e0 (&type->s_umount_key#90/1){+.+.}-{4:4}, at: alloc_super+0x244/0xd20 fs/super.c:345
#1: ffff888028129358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xa2/0xe40 block/bdev.c:961
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xd25/0x1050 kernel/hung_task.c:515
kthread+0x370/0x450 kernel/kthread.c:467
ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: a8 83 02 c3 cc cc cc cc 0f 1f 00 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 43 3c 1d 00 fb f4 bc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197df0 EFLAGS: 00000246
RAX: 00000000034ba3d7 RBX: ffff88801e6aa480 RCX: ffffffff8b8e4c75
RDX: 0000000000000000 RSI: ffffffff8de6ce9d RDI: ffffffff8c1adfa0
RBP: 0000000000000001 R08: 0000000000000001 R09: ffffed10170a6795
R10: ffff8880b8533cab R11: 0000000000000000 R12: ffffed1003cd5490
R13: 0000000000000001 R14: ffffffff90d92f10 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124452000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000404030 CR3: 000000007c50e000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:73 [inline]
default_idle+0x9/0x10 arch/x86/kernel/process.c:767
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x35b/0x4b0 kernel/sched/idle.c:332
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x148