INFO: task syz.0.5253:24894 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.5253 state:D stack:26824 pid:24894 tgid:24893 ppid:24017 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5360 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6964
__schedule_loop kernel/sched/core.c:7046 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7061
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7118
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
bdev_open+0xe0/0xd30 block/bdev.c:945
bdev_file_open_by_dev+0x1be/0x240 block/bdev.c:1059
setup_bdev_super+0x5a/0x5b0 fs/super.c:1609
get_tree_bdev_flags+0x366/0x4d0 fs/super.c:1689
vfs_get_tree+0x92/0x2b0 fs/super.c:1751
fc_mount fs/namespace.c:1274 [inline]
do_new_mount_fc fs/namespace.c:3726 [inline]
do_new_mount+0x302/0xa10 fs/namespace.c:3802
do_mount fs/namespace.c:4125 [inline]
__do_sys_mount fs/namespace.c:4324 [inline]
__se_sys_mount+0x313/0x410 fs/namespace.c:4301
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9200b8eba9
RSP: 002b:00007f920193f038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f9200dd5fa0 RCX: 00007f9200b8eba9
RDX: 0000200000000080 RSI: 0000200000000040 RDI: 0000200000000000
RBP: 00007f9200c11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000020080c4 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9200dd6038 R14: 00007f9200dd5fa0 R15: 00007ffe99eadd88
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e53c820 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e53c820 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e53c820 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:7/1161:
2 locks held by getty/5627:
#0: ffff88814e20a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036be2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by udevd/22473:
#0: ffff888143f51358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
2 locks held by syz.0.5253/24894:
#0: ffff888057f040e0 (&type->s_umount_key#107/1){+.+.}-{4:4}, at: alloc_super+0x1bb/0x930 fs/super.c:344
#1: ffff888143f51358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
1 lock held by syz.3.5564/26509:
#0: ffff888037de0420 (sb_writers#3){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160
2 locks held by syz.3.5564/26510:
#0: ffff8880314d47f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1232
#1: ffff888037de0420 (sb_writers#3){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3113 [inline]
#1: ffff888037de0420 (sb_writers#3){.+.+}-{0:0}, at: vfs_write+0x211/0xb30 fs/read_write.c:682
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 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: 3612 Comm: kworker/u8:12 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__local_bh_disable_ip+0x8/0x190 kernel/softirq.c:329
Code: 5d 41 5e 41 5f 5d c3 cc cc cc cc cc e8 41 4b 06 0a 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 48 89 e5 <41> 57 41 56 41 54 53 48 83 e4 e0 48 81 ec 80 00 00 00 89 f3 65 48
RSP: 0018:ffffc9000c73f940 EFLAGS: 00000282
RAX: ffff88802f7dc348 RBX: ffff88807b599040 RCX: 1ffff11005efb869
RDX: 0000000000000000 RSI: 0000000000000201 RDI: ffffffff8b598eb7
RBP: ffffc9000c73f940 R08: ffffffff8fe53a37 R09: 1ffffffff1fca746
R10: dffffc0000000000 R11: fffffbfff1fca747 R12: ffff88807e1c4208
R13: dffffc0000000000 R14: ffffffff8b598eb7 R15: ffff88802f7dc350
FS: 0000000000000000(0000) GS:ffff8881258a7000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe34bdaff8 CR3: 0000000076c66000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 0000000000000047 DR2: 0000000000000005
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:125 [inline]
_raw_spin_lock_bh+0x1c/0x50 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
batadv_nc_purge_paths+0xe7/0x3b0 net/batman-adv/network-coding.c:442
batadv_nc_worker+0x328/0x610 net/batman-adv/network-coding.c:720
process_one_work kernel/workqueue.c:3263 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245