INFO: task kworker/u8:10:6014 blocked for more than 143 seconds.
Not tainted 6.15.0-syzkaller-03589-gfeacb1774bd5 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:10 state:D stack:23592 pid:6014 tgid:6014 ppid:2 task_flags:0x4208160 flags:0x00004000
Workqueue: events_unbound netfs_write_collection_worker
Call Trace:
context_switch kernel/sched/core.c:5392 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6781
__schedule_loop kernel/sched/core.c:6859 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6874
bit_wait+0x15/0xe0 kernel/sched/wait_bit.c:237
__wait_on_bit+0x62/0x180 kernel/sched/wait_bit.c:49
out_of_line_wait_on_bit+0xd9/0x110 kernel/sched/wait_bit.c:64
wait_on_bit include/linux/wait_bit.h:77 [inline]
netfs_retry_writes+0x300/0x1a50 fs/netfs/write_retry.c:217
netfs_collect_write_results fs/netfs/write_collect.c:352 [inline]
netfs_write_collection_worker+0x23fd/0x3830 fs/netfs/write_collect.c:374
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3321 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
kthread+0x3c5/0x780 kernel/kthread.c:464
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:
1 lock held by khungtaskd/31:
#0: ffffffff8e3c27c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3c27c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e3c27c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770
2 locks held by getty/5575:
#0: ffff8880328750a0 (&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
2 locks held by kworker/u8:10/6014:
#0: ffff88801b481148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
#1: ffffc90005467d10 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
3 locks held by syz.1.957/9837:
#0: ffff888079646428 (sb_writers#21){.+.+}-{0:0}, at: do_pwritev+0x1a6/0x270 fs/read_write.c:1153
#1: ffff88807eab0148 (&sb->s_type->i_mutex_key#25){++++}-{4:4}, at: netfs_start_io_write+0x59/0x80 fs/netfs/locking.c:112
#2: ffff88807eab0500 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_begin_writethrough+0x64/0x1c0 fs/netfs/write_issue.c:624
1 lock held by syz.0.1518/11801:
#0: ffffffff8e3cdc40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3782
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-syzkaller-03589-gfeacb1774bd5 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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+0x3c5/0x780 kernel/kthread.c:464
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: 11802 Comm: syz.0.1518 Not tainted 6.15.0-syzkaller-03589-gfeacb1774bd5 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:stack_trace_save+0x92/0xc0 kernel/stacktrace.c:114
Code: e1 a6 81 89 74 24 28 48 8d 74 24 20 89 54 24 2c 48 c7 44 24 30 00 00 00 00 65 48 8b 15 ff 2a 01 12 e8 12 96 ba ff 8b 44 24 30 <48> c7 03 00 00 00 00 c7 43 08 00 00 00 00 48 8b 54 24 78 65 48 2b
RSP: 0018:ffffc9000fc37648 EFLAGS: 00000292
RAX: 000000000000000e RBX: fffff52001f86ec9 RCX: ffffc9000fc37514
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88805ac8ccc4
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000
R13: ffff88803360fd00 R14: ffffea0000ae1600 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88812499f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000007fe10000 CR4: 00000000003526f0
Call Trace:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:548
__call_rcu_common.constprop.0+0x9a/0x9f0 kernel/rcu/tree.c:3090
slab_free_hook mm/slub.c:2344 [inline]
slab_free mm/slub.c:4642 [inline]
kmem_cache_free+0x16d/0x4d0 mm/slub.c:4744
exit_mmap+0x511/0xb90 mm/mmap.c:1309
__mmput+0x12a/0x410 kernel/fork.c:1381
mmput+0x62/0x70 kernel/fork.c:1404
exit_mm kernel/exit.c:595 [inline]
do_exit+0xa3a/0x2c70 kernel/exit.c:947
do_group_exit+0xd3/0x2a0 kernel/exit.c:1108
get_signal+0x2673/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff8dc58e969
Code: Unable to access opcode bytes at 0x7ff8dc58e93f.
RSP: 002b:00007ff8dd3880e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007ff8dc7b5fa8 RCX: 00007ff8dc58e969
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007ff8dc7b5fa8
RBP: 00007ff8dc7b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff8dc7b5fac
R13: 0000000000000000 R14: 00007fff8e5d7000 R15: 00007fff8e5d70e8