INFO: task syz.8.1128:9084 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.1128 state:D stack:24920 pid:9084 tgid:9082 ppid:6768 task_flags:0x400040 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
io_schedule+0x80/0xd0 kernel/sched/core.c:7903
folio_wait_bit_common+0x6b0/0xb90 mm/filemap.c:1317
folio_wait_writeback+0xb0/0x100 mm/page-writeback.c:3124
__filemap_fdatawait_range+0x147/0x230 mm/filemap.c:539
filemap_fdatawait_keep_errors+0x31/0xd0 mm/filemap.c:633
wait_sb_inodes fs/fs-writeback.c:2715 [inline]
sync_inodes_sb+0x7a9/0xa10 fs/fs-writeback.c:2837
__iterate_supers+0x13d/0x290 fs/super.c:924
ksys_sync+0x94/0x150 fs/sync.c:102
__ia32_sys_sync+0xe/0x20 fs/sync.c:113
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f73ca18eba9
RSP: 002b:00007f73cafa5038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f73ca3d5fa0 RCX: 00007f73ca18eba9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f73ca3d5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f73ca3d6038 R14: 00007f73ca3d5fa0 R15: 00007ffe4f640ab8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:6/1138:
#0: ffff88801c7e7948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88801c7e7948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc90003ddfbc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc90003ddfbc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
2 locks held by kworker/u8:8/3004:
#0: ffff8880b8739f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:636
#1: ffff8880b8724008 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
2 locks held by getty/5624:
#0: ffff8880307990a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz.1.210/6532:
#0: ffff888032fa0428 (sb_writers#14){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3108 [inline]
#0: ffff888032fa0428 (sb_writers#14){.+.+}-{0:0}, at: vfs_writev+0x288/0x960 fs/read_write.c:1055
#1: ffff8880564a9498 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: netfs_start_io_direct+0x1ef/0x230 fs/netfs/locking.c:188
3 locks held by syz.4.1095/8988:
#0: ffff888029492428 (sb_writers#14){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3108 [inline]
#0: ffff888029492428 (sb_writers#14){.+.+}-{0:0}, at: vfs_writev+0x288/0x960 fs/read_write.c:1055
#1: ffff8880567d8148 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: netfs_start_io_write+0xd8/0x100 fs/netfs/locking.c:112
#2: ffff8880567d8500 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_begin_writethrough+0x65/0x140 fs/netfs/write_issue.c:626
2 locks held by syz.8.1128/9084:
#0: ffff8880294920e0 (&type->s_umount_key#58){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff8880294920e0 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
#1:
ffff888029492950 (&s->s_sync_lock){+.+.}-{4:4}, at: wait_sb_inodes fs/fs-writeback.c:2654 [inline]
ffff888029492950 (&s->s_sync_lock){+.+.}-{4:4}, at: sync_inodes_sb+0x255/0xa10 fs/fs-writeback.c:2837
1 lock held by syz-executor/9375:
#0: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#0: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957
=============================================
NMI backtrace for cpu 1
CPU: 1 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:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
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: 3004 Comm: kworker/u8:8 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:__lock_acquire+0x2d/0xd20 kernel/locking/lockdep.c:5093
Code: 41 56 41 55 41 54 53 48 83 ec 30 48 89 fb 65 48 8b 3c 25 08 b0 a0 92 45 31 ff 83 3d 0c 65 06 0e 00 0f 84 7e 0c 00 00 48 8b 03 <48> 3d 20 73 64 93 0f 84 6f 0c 00 00 41 89 cc 41 89 d6 8b 0d 6b 3c
RSP: 0018:ffffc9000b977840 EFLAGS: 00000002
RAX: ffffffff9a013740 RBX: ffff8880338b1998 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88802efc1e00
RBP: ffffffff8b4842f7 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f474a7 R12: 0000000000000000
R13: ffff8880338b1998 R14: 0000000000000001 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125c15000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555accd5c8 CR3: 0000000023a31000 CR4: 0000000000350ef0
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x36/0x50 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+0x369/0x610 net/batman-adv/network-coding.c:722
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245