INFO: task syz-executor.0:6245 blocked for more than 143 seconds.
Not tainted 6.15.0-rc4-syzkaller-00256-g95d3481af6dc #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0 state:D stack:28248 pid:6245 tgid:6244 ppid:6103 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
__mutex_lock_common kernel/locking/mutex.c:678 [inline]
__mutex_lock+0x6c7/0xb90 kernel/locking/mutex.c:746
bdev_release+0x15a/0x6d0 block/bdev.c:1128
blkdev_release+0x15/0x20 block/fops.c:660
__fput+0x3ff/0xb70 fs/file_table.c:465
task_work_run+0x14d/0x240 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f56b6c79b69
RSP: 002b:00007f56b7eb60c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f56b6d8bf80 RCX: 00007f56b6c79b69
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007f56b6cd534e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f56b6d8bf80 R15: 00007ffe4480eef8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764
2 locks held by getty/5570:
#0: ffff88803727a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000330b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
1 lock held by udevd/6106:
#0: ffff88802605b358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:945
1 lock held by syz-executor.0/6245:
#0: ffff88802605b358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x15a/0x6d0 block/bdev.c:1128
1 lock held by syz-executor.0/6475:
#0: ffff88802605b358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:945
1 lock held by syz-executor.0/6488:
#0: ffff88802605b358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:945
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc4-syzkaller-00256-g95d3481af6dc #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0xf70/0x12c0 kernel/hung_task.c:437
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
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: 3560 Comm: kworker/u8:8 Not tainted 6.15.0-rc4-syzkaller-00256-g95d3481af6dc #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
RIP: 0010:rcu_read_lock include/linux/rcupdate.h:841 [inline]
RIP: 0010:batadv_nc_process_nc_paths.part.0+0xc1/0x3e0 net/batman-adv/network-coding.c:687
Code: 28 e8 f3 f0 80 f6 48 8b 44 24 20 80 38 00 0f 85 21 03 00 00 48 8b 4c 24 18 48 63 44 24 14 48 8b 11 48 8d 1c c2 e8 3f 83 66 f6 <45> 31 c9 45 31 c0 b9 02 00 00 00 48 8d 05 00 00 00 00 50 31 d2 31
RSP: 0018:ffffc9000c76fac0 EFLAGS: 00000293
RAX: 0000000000000001 RBX: ffff88807a4939c0 RCX: ffff8880133bc900
RDX: 0000000000000000 RSI: ffffffff8b3a41fd RDI: ffff888032cda884
RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000000080
R10: 0000000000000038 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff888076f298a8 R14: 0000000000000038 R15: ffffffff8b3a38b0
FS: 0000000000000000(0000) GS:ffff888124ae1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000562a86aa5600 CR3: 000000000e180000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
batadv_nc_process_nc_paths net/batman-adv/network-coding.c:679 [inline]
batadv_nc_worker+0xcd3/0x1030 net/batman-adv/network-coding.c:728
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245