INFO: task kworker/u8:13:7244 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:13 state:D stack:20168 pid:7244 tgid:7244 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: netns cleanup_net
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
afs_cell_purge+0x3d9/0x540 fs/afs/cell.c:894
afs_net_exit+0x50/0x100 fs/afs/main.c:147
ops_exit_list net/core/net_namespace.c:199 [inline]
ops_undo_list+0x49a/0x990 net/core/net_namespace.c:252
cleanup_net+0x4de/0x820 net/core/net_namespace.c:695
process_one_work kernel/workqueue.c:3263 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 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:
9 locks held by ktimers/1/29:
1 lock held by khungtaskd/39:
#0: ffffffff8d5aa840 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d5aa840 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d5aa840 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5555:
#0: ffff88823bf688a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1400 drivers/tty/n_tty.c:2222
5 locks held by kworker/1:4/5873:
3 locks held by kworker/u8:13/7244:
#0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc9000482fba0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc9000482fba0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffffffff8e856360 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x820 net/core/net_namespace.c:669
1 lock held by syz.8.1886/16957:
2 locks held by syz.2.1889/16964:
2 locks held by syz.0.1890/16972:
1 lock held by udevadm/17000:
2 locks held by syz.6.1892/17006:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
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: 17007 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:preempt_count_sub+0x65/0x170 kernel/sched/core.c:5833
Code: ff ff ff 7f 39 cf 7f 2a 81 ff ff 00 00 00 0f 93 c1 84 c0 0f 95 c0 08 c8 74 5e 65 8b 05 44 b6 12 10 f7 df 65 01 3d 3b b6 12 10 <5b> 5d c3 cc cc cc cc cc 90 e8 3d 4c e6 02 85 c0 74 39 48 c7 c0 64
RSP: 0000:ffffc9000560f948 EFLAGS: 00000297
RAX: 0000000080000001 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: 0000000000000006 RSI: ffffffff8cf63f3d RDI: 00000000ffffffff
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff94000068b59 R12: dffffc0000000000
R13: 0000000000000008 R14: 0000000000000001 R15: ffff88813fffa760
FS: 00007fd7ada39c80(0000) GS:ffff888126ef9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd7adbf3380 CR3: 00000000569d2000 CR4: 00000000003526f0
Call Trace:
rcu_read_unlock_sched include/linux/rcupdate.h:981 [inline]
pfn_valid+0x3bc/0x490 include/linux/mmzone.h:2197
page_table_check_set+0x25/0x730 mm/page_table_check.c:105
page_table_check_ptes_set include/linux/page_table_check.h:76 [inline]
set_ptes include/linux/pgtable.h:292 [inline]
set_pte_range+0x6a5/0x700 mm/memory.c:5443
filemap_map_order0_folio mm/filemap.c:3790 [inline]
filemap_map_pages+0xb02/0x1990 mm/filemap.c:3848
do_fault_around mm/memory.c:5656 [inline]
do_read_fault mm/memory.c:5689 [inline]
do_fault mm/memory.c:5832 [inline]
do_pte_missing mm/memory.c:4361 [inline]
handle_pte_fault mm/memory.c:6177 [inline]
__handle_mm_fault mm/memory.c:6318 [inline]
handle_mm_fault+0x227f/0x3400 mm/memory.c:6487
do_user_addr_fault+0xa7c/0x1380 arch/x86/mm/fault.c:1336
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x82/0x100 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7fd7adbf3380
Code: 05 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d 71 fa 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 <48> 83 ec 10 48 63 ff 45 31 c9 45 31 c0 6a 03 31 c9 31 d2 31 f6 e8
RSP: 002b:00007ffdd8772b18 EFLAGS: 00010202
RAX: 000055d1a5529910 RBX: 000055d1a552b760 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 000055d1a5536710 RDI: 000000000000000b
RBP: 000055d1a55314c0 R08: 00007fd7adcd4b60 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 000055d1a5529910
R13: 000055d1a55314c0 R14: 0000000000000000 R15: 00007fd7adda3460