INFO: task kworker/u11:14:18006 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u11:14 state:D stack:24312 pid:18006 tgid:18006 ppid:2 task_flags:0x4208160 flags:0x00080000
Workqueue: netns cleanup_net
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7326
afs_cell_purge+0x46a/0x550 fs/afs/cell.c:921
afs_net_exit+0x83/0x150 fs/afs/main.c:147
ops_exit_list net/core/net_namespace.c:199 [inline]
ops_undo_list+0x2ee/0xab0 net/core/net_namespace.c:252
cleanup_net+0x499/0x920 net/core/net_namespace.c:702
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
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: ffffffff8e7e5ec0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e7e5ec0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8e7e5ec0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
3 locks held by kworker/u11:14/18006:
#0: ffff88801c6c6140 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc90004a6fd08 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffffffff906288e8 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xb8/0x920 net/core/net_namespace.c:673
2 locks held by getty/29278:
#0: ffff88803698a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900038752e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211
1 lock held by syz.4.5956/583:
#0: ffff88807e3303b8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock_killable include/linux/mmap_lock.h:601 [inline]
#0: ffff88807e3303b8 (&mm->mmap_lock){++++}-{4:4}, at: __get_user_pages_locked mm/gup.c:1744 [inline]
#0: ffff88807e3303b8 (&mm->mmap_lock){++++}-{4:4}, at: faultin_page_range+0x3c7/0x9e0 mm/gup.c:1912
1 lock held by syz.4.5956/591:
#0: ffff88807e3303b8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock_killable include/linux/mmap_lock.h:601 [inline]
#0: ffff88807e3303b8 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:450 [inline]
#0: ffff88807e3303b8 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x160/0x6f0 mm/mmap_lock.c:501
4 locks held by syz.4.5956/609:
2 locks held by syz.4.5956/629:
#0: ffffffff8e92a630 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1537 [inline]
#0: ffffffff8e92a630 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm kernel/fork.c:1590 [inline]
#0: ffffffff8e92a630 (dup_mmap_sem){.+.+}-{0:0}, at: copy_process+0x457d/0x8030 kernel/fork.c:2288
#1: ffff88807e3303b8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline]
#1: ffff88807e3303b8 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x125/0x21b0 mm/mmap.c:1739
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x21c/0x2a0 lib/nmi_backtrace.c:65
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xcb1/0x1030 kernel/hung_task.c:561
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245