INFO: task kworker/u8:2:36 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:2 state:D stack:23560 pid:36 tgid:36 ppid:2 task_flags:0x4248060 flags:0x00004000
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
io_schedule+0xbf/0x130 kernel/sched/core.c:7903
rq_qos_wait+0x22f/0x340 block/blk-rq-qos.c:307
__wbt_wait block/blk-wbt.c:596 [inline]
wbt_wait+0x1af/0x390 block/blk-wbt.c:656
__rq_qos_throttle+0x56/0xa0 block/blk-rq-qos.c:66
rq_qos_throttle block/blk-rq-qos.h:168 [inline]
rq_qos_throttle block/blk-rq-qos.h:163 [inline]
blk_mq_get_new_requests block/blk-mq.c:3033 [inline]
blk_mq_submit_bio+0x2174/0x2a10 block/blk-mq.c:3183
__submit_bio+0x3cf/0x690 block/blk-core.c:635
__submit_bio_noacct_mq block/blk-core.c:722 [inline]
submit_bio_noacct_nocheck+0x660/0xd30 block/blk-core.c:751
submit_bio_noacct+0xc20/0x1ed0 block/blk-core.c:874
ext4_io_submit+0xa6/0x140 fs/ext4/page-io.c:404
ext4_do_writepages+0xa2a/0x3cf0 fs/ext4/inode.c:2881
ext4_writepages+0x37a/0x7d0 fs/ext4/inode.c:3025
do_writepages+0x27a/0x600 mm/page-writeback.c:2634
__writeback_single_inode+0x160/0xfb0 fs/fs-writeback.c:1680
writeback_sb_inodes+0x60d/0xfa0 fs/fs-writeback.c:1976
__writeback_inodes_wb+0xf8/0x2d0 fs/fs-writeback.c:2047
wb_writeback+0x7f3/0xb70 fs/fs-writeback.c:2158
wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
wb_do_writeback fs/fs-writeback.c:2315 [inline]
wb_workfn+0x8ca/0xbe0 fs/fs-writeback.c:2343
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:2/36:
#0: ffff888142a85148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc90000ac7d10 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff88803501e0e0 (&type->s_umount_key#32){++++}-{4:4}, at: super_trylock_shared+0x1e/0xf0 fs/super.c:563
#3: ffff8880352e0b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: do_writepages+0x27a/0x600 mm/page-writeback.c:2634
6 locks held by kworker/u8:6/1097:
#0: ffff88801b889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc900042efd10 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff888032db80d8 (key#17){+...}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
#2: ffff888032db80d8 (key#17){+...}-{3:3}, at: batadv_nc_purge_paths+0xd9/0x3a0 net/batman-adv/network-coding.c:442
#3: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#3: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#3: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: ieee80211_sta_active_ibss+0xdc/0x420 net/mac80211/ibss.c:635
#4: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#4: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#4: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
#4: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x20a0 arch/x86/kernel/unwind_orc.c:479
#5: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#5: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#5: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: ___pte_offset_map+0x33/0x4f0 mm/pgtable-generic.c:286
2 locks held by getty/5626:
#0: ffff88803534f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
3 locks held by syz.0.119/6696:
#0: ffff8880725bea88 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11b/0x530 mm/mmap_lock.c:147
#1: ffff88803501e520 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x174/0x380 mm/memory.c:3361
#2: ffff8880352e2950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x5e4/0x1410 fs/jbd2/transaction.c:444
3 locks held by syz-executor/6697:
#0: ffff88803501e428 (sb_writers#4){.+.+}-{0:0}, at: filename_create+0x10e/0x4a0 fs/namei.c:4132
#1: ffff88807ea5c6d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:915 [inline]
#1: ffff88807ea5c6d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_create+0x1bb/0x4a0 fs/namei.c:4139
#2: ffff8880352e2950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x5e4/0x1410 fs/jbd2/transaction.c:444
=============================================
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 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:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf0e/0x1260 kernel/hung_task.c:491
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
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: 49 Comm: kworker/u8:3 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:mark_lock+0x94/0x610 kernel/locking/lockdep.c:4774
Code: 80 48 8d 04 c5 60 f9 dc 95 4c 89 ea 48 23 50 60 b8 01 00 00 00 74 7f 48 8b 54 24 68 65 48 2b 15 0a fb 3e 12 0f 85 e8 04 00 00 <48> 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d e9 c9 fb fc 09 f6 46 22
RSP: 0018:ffffc90000b978b0 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000006 RCX: 0000000000000006
RDX: 0000000000000000 RSI: ffff888022e82940 RDI: ffff888022e81e00
RBP: ffffc90000b97948 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000050 R11: 0000000000000001 R12: ffff888022e82940
R13: 0000000000000040 R14: 0000000000000002 R15: ffff888022e81e00
FS: 0000000000000000(0000) GS:ffff8881247bd000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000562ba6a81088 CR3: 000000000e380000 CR4: 00000000003526f0
Call Trace:
mark_usage kernel/locking/lockdep.c:4666 [inline]
__lock_acquire+0x3e4/0x1ce0 kernel/locking/lockdep.c:5191
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825
__mutex_lock_common kernel/locking/mutex.c:598 [inline]
__mutex_lock+0x193/0x1060 kernel/locking/mutex.c:760
class_wiphy_constructor include/net/cfg80211.h:6212 [inline]
cfg80211_wiphy_work+0x99/0x580 net/wireless/core.c:421
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245