INFO: task kworker/u8:3:49 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kerne[ 522.628336][ T38] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:3 state:D stack:21312 pid:49 tgid:49 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: netns cleanup_net
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6908
__schedule_loop kernel/sched/core.c:6990 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7005
afs_cell_purge+0x40d/0x580 fs/afs/cell.c:921
afs_net_exit+0x50/0x100 fs/afs/main.c:147
ops_exit_list net/core/net_namespace.c:199 [inline]
ops_undo_list+0x49f/0x940 net/core/net_namespace.c:252
cleanup_net+0x56e/0x800 net/core/net_namespace.c:704
process_one_work kernel/workqueue.c:3275 [inline]
process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358
worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 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:
2 locks held by kworker/u8:0/12:
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358
#1: ffffc90000117c40 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc90000117c40 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358
1 lock held by khungtaskd/38:
#0: ffffffff8ddcb840 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8ddcb840 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8ddcb840 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:3/49:
#0: ffff88801aee1138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff88801aee1138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358
#1: ffffc90000bb7c40 (
net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358
#2: ffffffff8f14b840 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:675
1 lock held by udevd/5164:
2 locks held by getty/5554:
#0: ffff88803850f0a0 (&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+0x462/0x13c0 drivers/tty/n_tty.c:2211
2 locks held by udevd/5927:
2 locks held by udevd/6652:
#0: ffff88802252fb68 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline]
#0: ffff88802252fb68 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_read_iter+0x2ff/0x440 block/fops.c:854
#1: ffff88802252fd38 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1093 [inline]
#1: ffff88802252fd38 (mapping.invalidate_lock){++++}-{4:4}, at: do_page_cache_ra mm/readahead.c:333 [inline]
#1: ffff88802252fd38 (mapping.invalidate_lock){++++}-{4:4}, at: force_page_cache_ra+0x263/0x2e0 mm/readahead.c:364
1 lock held by syz-executor/9705:
#0: ffff888062a400d0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff888062a400d0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff888062a400d0 (&type->s_umount_key#32){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
10 locks held by syz-executor/10864:
6 locks held by syz.0.891/12661:
2 locks held by syz.2.892/12671:
#0: ffff8880212ea0d0 (&type->s_umount_key#67/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xac0 fs/super.c:345
#1: ffff88802252fd38 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock include/linux/fs.h:1083 [inline]
#1: ffff88802252fd38 (mapping.invalidate_lock){++++}-{4:4}, at: btrfs_read_disk_super+0x1fd/0x530 fs/btrfs/volumes.c:1371
1 lock held by syz.3.897/12680:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 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: 12661 Comm: syz.0.891 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:kasan_check_range+0x5/0x2c0 mm/kasan/generic.c:199
Code: 48 c7 c6 14 ce 7b 8d e8 99 68 fd fe 90 0f 0b cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 55 <41> 57 41 56 41 55 41 54 53 b0 01 48 85 f6 0f 84 ae 01 00 00 4c 8d
RSP: 0018:ffffc90004357458 EFLAGS: 00000246
RAX: 1ffff11027fff8da RBX: 0000000000000000 RCX: ffffffff821c3ce0
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88813fffc680
RBP: 0000000000000001 R08: ffff88813fffc6d7 R09: 1ffff11027fff8da
R10: dffffc0000000000 R11: ffffed1027fff8db R12: ffffea00019cf648
R13: 0000000000000000 R14: ffff88813fffc6d0 R15: ffff88813fffc680
FS: 00007f3646fe66c0(0000) GS:ffff88812643f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f01913f5900 CR3: 000000006582c000 CR4: 00000000003526f0
Call Trace:
instrument_atomic_read include/linux/instrumented.h:82 [inline]
atomic_long_read include/linux/atomic/atomic-instrumented.h:3188 [inline]
zone_page_state include/linux/vmstat.h:207 [inline]
__rmqueue mm/page_alloc.c:2491 [inline]
rmqueue_bulk mm/page_alloc.c:2562 [inline]
__rmqueue_pcplist+0x610/0x1b80 mm/page_alloc.c:3349
rmqueue_pcplist mm/page_alloc.c:3388 [inline]
rmqueue mm/page_alloc.c:3418 [inline]
get_page_from_freelist+0x9ee/0x2950 mm/page_alloc.c:3959
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250
alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2484
folio_alloc_mpol_noprof+0x39/0xe0 mm/mempolicy.c:2503
shmem_alloc_folio mm/shmem.c:1930 [inline]
shmem_alloc_and_add_folio mm/shmem.c:1972 [inline]
shmem_get_folio_gfp+0x644/0x1a80 mm/shmem.c:2567
shmem_get_folio mm/shmem.c:2673 [inline]
shmem_write_begin+0x166/0x320 mm/shmem.c:3327
generic_perform_write+0x2af/0x8b0 mm/filemap.c:4319
shmem_file_write_iter+0xfb/0x120 mm/shmem.c:3502
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x629/0xba0 fs/read_write.c:688
ksys_write+0x156/0x270 fs/read_write.c:740
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3648d4cfce
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007f3646fe5da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f3646fe66c0 RCX: 00007f3648d4cfce
RDX: 00000000013bd7ef RSI: 00007f363ebc6000 RDI: 0000000000000006
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
R13: 00007f3646fe5ee0 R14: 00007f3646fe5ea0 R15: 00007f363ebc6000