INFO: task syz.1.3843:22145 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.1.3843 state:D stack:25672 pid:22145 tgid:22143 ppid:19217 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1295/0x67a0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7283
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820
bdev_open+0xa2/0xe40 block/bdev.c:953
bdev_file_open_by_dev block/bdev.c:1067 [inline]
bdev_file_open_by_dev+0x179/0x210 block/bdev.c:1042
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:3758 [inline]
do_new_mount fs/namespace.c:3834 [inline]
path_mount+0x7d0/0x23d0 fs/namespace.c:4154
do_mount fs/namespace.c:4167 [inline]
__do_sys_mount fs/namespace.c:4383 [inline]
__se_sys_mount fs/namespace.c:4360 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4360
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3be6f9ce59
RSP: 002b:00007f3be7df7028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f3be7216090 RCX: 00007f3be6f9ce59
RDX: 0000200000000080 RSI: 0000200000000040 RDI: 0000200000000000
RBP: 00007f3be7032d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000001a0c000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3be7216128 R14: 00007f3be7216090 R15: 00007ffc58e71ff8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e7e5760 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e7e5760 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e7e5760 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
1 lock held by klogd/4968:
#0: ffff8880b843b2a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:660 [inline]
#0: ffff8880b843b2a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x88/0x140 kernel/sched/core.c:644
2 locks held by getty/5366:
#0: ffff888038d2f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211
2 locks held by kworker/u8:38/5952:
#0: ffff88813fe94140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289
#1: ffffc90005557d08 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290
1 lock held by udevd/18195:
#0: ffff88802840f350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:953
1 lock held by udevd/18250:
#0: ffff8880284bb350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:953
2 locks held by syz.1.3843/22145:
#0: ffff8880277280d8 (&type->s_umount_key#100/1){+.+.}-{4:4}, at: alloc_super+0x244/0xd20 fs/super.c:345
#1: ffff88802840f350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xa2/0xe40 block/bdev.c:953
1 lock held by syz.7.4381/24297:
#0: ffffffff8e7f1178 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6d0 kernel/rcu/tree.c:3828
3 locks held by syz.5.4383/24302:
#0: ffff88805992ee40 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline]
#0: ffff88805992ee40 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x86/0x260 net/socket.c:721
#1: ffff888077f21260 (sk_lock-AF_CAN){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline]
#1: ffff888077f21260 (sk_lock-AF_CAN){+.+.}-{0:0}, at: bcm_release+0x1fa/0x9d0 net/can/bcm.c:1611
#2: ffffffff8e7f12a8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
=============================================
NMI backtrace for cpu 1
CPU: 1 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 04/18/2026
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:162 [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:353 [inline]
watchdog+0xcb1/0x1030 kernel/hung_task.c:561
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
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: 24310 Comm: syz.5.4383 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:debug_spin_unlock kernel/locking/spinlock_debug.c:106 [inline]
RIP: 0010:do_raw_spin_unlock+0x11d/0x1e0 kernel/locking/spinlock_debug.c:141
Code: 00 fc ff df 4c 89 e2 48 c1 ea 03 80 3c 02 00 0f 85 bd 00 00 00 48 89 ea 48 c7 43 10 ff ff ff ff 48 b8 00 00 00 00 00 fc ff df <48> c1 ea 03 0f b6 14 02 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 04 84
RSP: 0018:ffffc900052ff738 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffffffff9b349af8 RCX: ffffffff81e4d363
RDX: ffffffff9b349b00 RSI: 0000000000000004 RDI: ffffffff9b349af8
RBP: ffffffff9b349b00 R08: 0000000000000000 R09: fffffbfff366935f
R10: ffffffff9b349afb R11: 0000000000000000 R12: ffffffff9b349b08
R13: ffff888051116000 R14: ffffc900052ffa58 R15: 1ffff92000a5fef2
FS: 0000000000000000(0000) GS:ffff888124370000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2820dea2f8 CR3: 000000007849a000 CR4: 00000000003526f0
Call Trace:
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:177 [inline]
_raw_spin_unlock_irqrestore+0x22/0x80 kernel/locking/spinlock.c:198
debug_object_activate+0x331/0x490 lib/debugobjects.c:853
debug_rcu_head_queue kernel/rcu/rcu.h:236 [inline]
__call_rcu_common.constprop.0+0x35/0x9b0 kernel/rcu/tree.c:3116
tlb_remove_table_free mm/mmu_gather.c:296 [inline]
tlb_table_flush mm/mmu_gather.c:377 [inline]
tlb_table_flush mm/mmu_gather.c:371 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:415 [inline]
tlb_flush_mmu mm/mmu_gather.c:424 [inline]
tlb_finish_mmu+0x163/0x810 mm/mmu_gather.c:549
exit_mmap+0x454/0xa10 mm/mmap.c:1313
__mmput+0x12a/0x410 kernel/fork.c:1178
mmput+0x67/0x80 kernel/fork.c:1201
exit_mm kernel/exit.c:582 [inline]
do_exit+0x8b2/0x2af0 kernel/exit.c:964
do_group_exit+0xd5/0x2a0 kernel/exit.c:1119
get_signal+0x20ff/0x2210 kernel/signal.c:3037
arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0x8b/0x4f0 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x706/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fefc2f9ce59
Code: Unable to access opcode bytes at 0x7fefc2f9ce2f.
RSP: 002b:00007fefc3e7f0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fefc3216098 RCX: 00007fefc2f9ce59
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fefc3216098
RBP: 00007fefc3216090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fefc3216128 R14: 00007ffd0aedecb0 R15: 00007ffd0aeded98