INFO: task syz.0.1452:10912 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1452 state:D stack:28808 pid:10912 tgid:10910 ppid:5608 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5584 [inline]
__schedule+0x1b47/0x5b40 kernel/sched/core.c:7387
__schedule_loop kernel/sched/core.c:7464 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7479
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7536
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0x7c4/0x15a0 kernel/locking/mutex.c:821
bdev_open+0xde/0xd70 block/bdev.c:990
bdev_file_open_by_dev+0x1be/0x240 block/bdev.c:1104
fs_bdev_file_open_by_dev fs/super.c:1710 [inline]
setup_bdev_super+0x5a/0x680 fs/super.c:1802
get_tree_bdev_flags+0x388/0x4f0 fs/super.c:1881
vfs_get_tree+0x92/0x2a0 fs/super.c:1943
fc_mount fs/namespace.c:1278 [inline]
do_new_mount_fc fs/namespace.c:3901 [inline]
do_new_mount+0x325/0xb00 fs/namespace.c:3977
do_mount fs/namespace.c:4341 [inline]
__do_sys_mount fs/namespace.c:4556 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4533
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbd3739e199
RSP: 002b:00007fbd381ec028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fbd37625fa0 RCX: 00007fbd3739e199
RDX: 0000200000000080 RSI: 00002000000000c0 RDI: 0000200000000000
RBP: 00007fbd374358e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000200011 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbd37626038 R14: 00007fbd37625fa0 R15: 00007ffde250fb38
Showing all locks held in the system:
locks held by khungtaskd/33: 1, last CPU#0:
#0: ffffffff8f15a260 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8f15a260 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8f15a260 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871
locks held by kworker/0:3/2252: 2, last CPU#0:
#0: ffff88813fe09d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88813fe09d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88813fe09d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#0: ffff88813fe09d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#1: ffffc90006a0fc40 ((gc_work).work){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90006a0fc40 ((gc_work).work){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90006a0fc40 ((gc_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#1: ffffc90006a0fc40 ((gc_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
locks held by udevd/5791: 1, on CPU#0:
#0: ffff88802802a350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd70 block/bdev.c:990
locks held by syz.0.1452/10912: 2, on CPU#1:
#0: ffff888079ca40e8 (&type->s_umount_key#30/1){+.+.}-{4:4}, at: alloc_super fs/super.c:351 [inline]
#0: ffff888079ca40e8 (&type->s_umount_key#30/1){+.+.}-{4:4}, at: sget_fc+0x9cf/0x1a60 fs/super.c:874
#1: ffff88802802a350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd70 block/bdev.c:990
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 33 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:377 [inline]
watchdog+0x1073/0x10f0 kernel/hung_task.c:598
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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 09/16/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: 2b a5 02 e9 03 18 03 00 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 43 59 2a 00 fb f4 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc900001c7e40 EFLAGS: 00000246
RAX: 0000000000576709 RBX: ffffffff819c5f50 RCX: 8000000000000001
RDX: 0000000000000001 RSI: ffffffff8e771c69 RDI: ffffffff8c8f4780
RBP: ffffc900001c7f10 R08: ffff8880b8533e5b R09: 1ffff110170a67cb
R10: dffffc0000000000 R11: ffffed10170a67cc R12: 0000000000000000
R13: 1ffff11003c563e8 R14: 1ffff92000038fd0 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888124733000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcd99a1000 CR3: 0000000077c1c000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/kernel/process.c:767 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:768
default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x2e0/0x540 kernel/sched/idle.c:355
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:454
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x157