INFO: task kworker/u8:10:5982 blocked for more than 143 seconds.
Not tainted 6.15.0-rc1-syzkaller-00025-gbec7dcbc242c #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:10 state:D stack:23616 pid:5982 tgid:5982 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: events_unbound netfs_write_collection_worker
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b33/0x51f0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6860
bit_wait+0x12/0xd0 kernel/sched/wait_bit.c:237
__wait_on_bit+0xb0/0x300 kernel/sched/wait_bit.c:49
out_of_line_wait_on_bit+0x1e0/0x280 kernel/sched/wait_bit.c:64
wait_on_bit include/linux/wait_bit.h:77 [inline]
netfs_retry_writes+0x170/0x19d0 fs/netfs/write_retry.c:217
netfs_collect_write_results fs/netfs/write_collect.c:352 [inline]
netfs_write_collection_worker+0x2fc0/0x3bf0 fs/netfs/write_collect.c:374
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
worker_thread+0x870/0xd50 kernel/workqueue.c:3400
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Showing all locks held in the system:
2 locks held by ksoftirqd/1/23:
1 lock held by khungtaskd/31:
#0: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764
3 locks held by kworker/u8:4/63:
#0: ffff88801bef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801bef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc90001567c60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90001567c60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
#2: ffffffff900de5d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17c/0xd60 net/core/net_namespace.c:608
2 locks held by getty/5583:
#0: ffff8880318ad0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036d62f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222
2 locks held by kworker/u8:10/5982:
#0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc900048bfc60 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900048bfc60 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
2 locks held by syz.3.42/6080:
#0: ffff88802a5ba420 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline]
#0: ffff88802a5ba420 (sb_writers#13){.+.+}-{0:0}, at: vfs_writev+0x2d8/0xbc0 fs/read_write.c:1053
#1: ffff88805c4f8148 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: netfs_start_io_direct+0x1d4/0x210 fs/netfs/locking.c:188
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc1-syzkaller-00025-gbec7dcbc242c #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 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+0x1058/0x10a0 kernel/hung_task.c:437
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/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: 6996 Comm: kworker/u8:17 Not tainted 6.15.0-rc1-syzkaller-00025-gbec7dcbc242c #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x5a/0xb0 kernel/rcu/tree.c:736
Code: f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 6c 37 82 00 48 c7 c3 58 9b 66 93 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 <84> c0 75 22 8b 03 65 ff 0d 69 cb bc 11 74 10 83 e0 04 c1 e8 02 5b
RSP: 0018:ffffc90003d87388 EFLAGS: 00000a02
RAX: 0000000000000000 RBX: ffff8880b8732b58 RCX: ffff888026081e00
RDX: 0000000000000000 RSI: ffffffff8ca0e240 RDI: ffffffff8ca0e200
RBP: ffffc90003d87518 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffc90003d874e0
R13: dffffc0000000000 R14: ffffffff8e783c18 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8881250c9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fddc3f79178 CR3: 000000000eb38000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rcu_read_lock include/linux/rcupdate.h:842 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xe7/0x23b0 arch/x86/kernel/unwind_orc.c:479
__unwind_start+0x59a/0x740 arch/x86/kernel/unwind_orc.c:758
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe7/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x11a/0x1d0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0x9d/0xb0 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:260 [inline]
__do_kmalloc_node mm/slub.c:4331 [inline]
__kmalloc_node_track_caller_noprof+0x295/0x4d0 mm/slub.c:4350
kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:599
__alloc_skb+0x1f2/0x480 net/core/skbuff.c:668
alloc_skb include/linux/skbuff.h:1340 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
nsim_dev_trap_report_work+0x260/0xb50 drivers/net/netdevsim/dev.c:851
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
worker_thread+0x870/0xd50 kernel/workqueue.c:3400
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245