INFO: task kworker/u8:8:4902 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:8 state:D stack:22344 pid:4902 tgid:4902 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: events_unbound netfs_write_collection_worker
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
netfs_wait_for_in_progress_stream+0x17a/0x440 fs/netfs/misc.c:370
netfs_retry_writes+0x1394/0x19c0 fs/netfs/write_retry.c:214
netfs_collect_write_results fs/netfs/write_collect.c:349 [inline]
netfs_write_collection+0x19ee/0x36d0 fs/netfs/write_collect.c:365
netfs_write_collection_worker+0xea/0x1d0 fs/netfs/write_collect.c:448
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3236
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c2/0x780 kernel/kthread.c:463
ret_from_fork+0x5d4/0x6f0 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:
2 locks held by kworker/u8:0/12:
#0: ffff88801b881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc90000117d10 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
2 locks held by kworker/u8:1/13:
#0: ffff88801b881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc90000127d10 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
1 lock held by khungtaskd/31:
#0: ffffffff8e5c1260 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5c1260 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e5c1260 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:2/36:
#0: ffff88801b881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc90000ac7d10 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
2 locks held by kworker/u8:3/37:
#0: ffff88801b881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc90000ad7d10 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
2 locks held by kworker/u8:4/74:
#0: ffff88801b881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc9000211fd10 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
2 locks held by kworker/u8:5/1163:
#0: ffff88801b881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc90003cbfd10 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
2 locks held by kworker/u8:6/1635:
#0: ffff88801b881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc90004a0fd10 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
2 locks held by kworker/u8:8/4902:
#0: ffff88801b881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc9000f3e7d10 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
2 locks held by getty/5607:
#0: ffff88814e27e0a0 (&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
1 lock held by syz.0.17/6479:
#0: ffff888057c00500 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0xba/0x920 fs/netfs/write_issue.c:559
1 lock held by syz.1.18/6502:
#0: ffff8880732b0500 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0xba/0x920 fs/netfs/write_issue.c:559
1 lock held by syz.2.19/6525:
#0: ffff8880732b0b70 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0xba/0x920 fs/netfs/write_issue.c:559
1 lock held by syz.3.20/6549:
#0: ffff888057c00b70 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0xba/0x920 fs/netfs/write_issue.c:559
1 lock held by syz.4.21/6584:
#0: ffff8880732b11e0 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0xba/0x920 fs/netfs/write_issue.c:559
1 lock held by syz.5.22/6615:
#0: ffff888057c011e0 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0xba/0x920 fs/netfs/write_issue.c:559
1 lock held by syz.6.23/6644:
#0: ffff888057c01850 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0xba/0x920 fs/netfs/write_issue.c:559
2 locks held by kworker/u8:12/6647:
#0: ffff88801b881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc900042dfd10 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
1 lock held by syz.7.24/6680:
#0: ffff888057c01ec0 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0xba/0x920 fs/netfs/write_issue.c:559
2 locks held by kworker/u8:13/6701:
#0: ffff88801b881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc9000453fd10 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
1 lock held by syz.8.25/6712:
#0: ffff8880732b1850 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0xba/0x920 fs/netfs/write_issue.c:559
1 lock held by syz.9.27/6746:
#0: ffff8880732b1ec0 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0xba/0x920 fs/netfs/write_issue.c:559
=============================================
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 07/12/2025
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+0x3c2/0x780 kernel/kthread.c:463
ret_from_fork+0x5d4/0x6f0 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: 6587 Comm: kworker/u8:10 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:hlock_class kernel/locking/lockdep.c:229 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4879 [inline]
RIP: 0010:__lock_acquire+0x32c/0x1ce0 kernel/locking/lockdep.c:5187
Code: 74 0f 38 c2 0f 47 d0 80 b9 c6 00 00 00 02 0f 44 d0 41 83 c6 01 45 3b b5 e8 0a 00 00 7d 2f 49 63 c6 48 8d 04 80 0f b7 44 c3 20 <66> 25 ff 1f 0f b7 c0 48 0f a3 05 a5 ce 45 14 72 ac 8b 05 bd 79 4e
RSP: 0018:ffffc90003f16bd0 EFLAGS: 00000002
RAX: 00000000000000cd RBX: ffff88807e35af30 RCX: 0000000000000000
RDX: 0000000000000005 RSI: 0000000000000004 RDI: ffff88807e35afd0
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000000a0 R11: 0000000000000001 R12: ffff88807e35afd0
R13: ffff88807e35a440 R14: 0000000000000000 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8881246b5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555f1035c8 CR3: 000000000e380000 CR4: 00000000003526f0
Call Trace:
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:243 [inline]
__kasan_slab_free+0x60/0x70 mm/kasan/common.c:275
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2422 [inline]
slab_free mm/slub.c:4695 [inline]
kfree+0x2b4/0x4d0 mm/slub.c:4894
ieee80211_inform_bss+0x77c/0x1140 net/mac80211/scan.c:160
rdev_inform_bss net/wireless/rdev-ops.h:418 [inline]
cfg80211_inform_single_bss_data+0x8ea/0x1df0 net/wireless/scan.c:2380
cfg80211_inform_bss_data+0x224/0x3bd0 net/wireless/scan.c:3235
cfg80211_inform_bss_frame_data+0x26f/0x750 net/wireless/scan.c:3326
ieee80211_bss_info_update+0x310/0xab0 net/mac80211/scan.c:226
ieee80211_rx_bss_info net/mac80211/ibss.c:1094 [inline]
ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1573 [inline]
ieee80211_ibss_rx_queued_mgmt+0x1905/0x2fd0 net/mac80211/ibss.c:1600
ieee80211_iface_process_skb net/mac80211/iface.c:1699 [inline]
ieee80211_iface_work+0xe2e/0x1360 net/mac80211/iface.c:1753
cfg80211_wiphy_work+0x2c7/0x580 net/wireless/core.c:435
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3236
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c2/0x780 kernel/kthread.c:463
ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245