INFO: task kworker/u8:4:62 blocked for more than 143 seconds.
Not tainted 6.15.0-rc6-syzkaller-00080-g1a80a098c606 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:4 state:D stack:23488 pid:62 tgid:62 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:2)
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x168f/0x4c70 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
__mutex_lock_common kernel/locking/mutex.c:678 [inline]
__mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746
jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102
jfs_write_inode+0x145/0x220 fs/jfs/inode.c:132
write_inode fs/fs-writeback.c:1525 [inline]
__writeback_single_inode+0x6f1/0xff0 fs/fs-writeback.c:1745
writeback_sb_inodes+0x6b5/0x1000 fs/fs-writeback.c:1976
__writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2047
wb_writeback+0x44f/0xaf0 fs/fs-writeback.c:2158
wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
wb_do_writeback fs/fs-writeback.c:2315 [inline]
wb_workfn+0xaef/0xef0 fs/fs-writeback.c:2343
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x70e/0x8a0 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:
4 locks held by kworker/u8:1/13:
1 lock held by khungtaskd/31:
#0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
4 locks held by kworker/u8:4/62:
#0: ffff888020aca948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff888020aca948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc9000154fc60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000154fc60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffff88805c37a0e0 (&type->s_umount_key#52){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:562
#3: ffff88805917b918 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102
4 locks held by kworker/u8:5/1084:
#0: ffff88801aef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801aef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc90003d8fc60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90003d8fc60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffffffff8f2d84d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x145/0xbd0 net/core/net_namespace.c:608
#3: ffff888033c014e8 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_destruct+0x116/0x2f0 drivers/net/wireguard/device.c:249
2 locks held by kworker/u8:6/1109:
1 lock held by dhcpcd/5483:
#0: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x5b7/0xd20 net/ipv6/addrconf.c:5031
2 locks held by getty/5583:
#0: ffff8880309c10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by kworker/0:7/5931:
4 locks held by syz.2.92/6545:
1 lock held by syz-executor/8295:
#0: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4064
2 locks held by syz-executor/8355:
#0: ffffffff8ea7e8e0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8ea7e8e0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8ea7e8e0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4064
2 locks held by syz.8.366/8624:
2 locks held by dhcpcd/8635:
#0: ffff88807d782258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline]
#0: ffff88807d782258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0 net/packet/af_packet.c:3252
#1: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#1: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998
2 locks held by dhcpcd/8636:
#0: ffff88805dcf8258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline]
#0: ffff88805dcf8258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0 net/packet/af_packet.c:3252
#1: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#1: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998
1 lock held by dhcpcd/8637:
#0: ffff88803280a258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline]
#0: ffff88803280a258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0 net/packet/af_packet.c:3252
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-00080-g1a80a098c606 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:437
kthread+0x70e/0x8a0 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: 5188 Comm: udevd Not tainted 6.15.0-rc6-syzkaller-00080-g1a80a098c606 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:lock_release+0x2a2/0x3e0 kernel/locking/lockdep.c:5890
Code: b1 09 b8 ff ff ff ff 65 0f c1 05 29 3a d4 10 83 f8 01 75 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 <75> 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 db fd d3 10 48 3b 44
RSP: 0018:ffffc9000eb177f8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000206 RCX: 6b5208e017756900
RDX: 0000000000000000 RSI: ffffffff8d9226fd RDI: ffffffff8bc104e0
RBP: ffff88807cc48af0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff81ab5c1d R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff8df3dce0 R15: ffff88807cc48000
FS: 00007f7f6917b880(0000) GS:ffff8881261fb000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555bd77608 CR3: 0000000076d64000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
is_module_text_address+0x18b/0x1e0 kernel/module/main.c:3745
kernel_text_address+0x94/0xe0 kernel/extable.c:119
__kernel_text_address+0xd/0x40 kernel/extable.c:79
unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369
arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:260 [inline]
__kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4358
kmalloc_noprof include/linux/slab.h:905 [inline]
kzalloc_noprof include/linux/slab.h:1039 [inline]
kernfs_iop_get_link+0x66/0x6c0 fs/kernfs/symlink.c:137
vfs_readlink+0x24a/0x550 fs/namei.c:5367
do_readlinkat+0x215/0x500 fs/stat.c:582
__do_sys_readlink fs/stat.c:605 [inline]
__se_sys_readlink fs/stat.c:602 [inline]
__x64_sys_readlink+0x7f/0x90 fs/stat.c:602
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7f68b153a7
Code: 00 00 90 48 83 ec 10 48 63 ff 45 31 c9 45 31 c0 6a 00 31 c9 e8 8a 20 f9 ff 48 83 c4 18 c3 0f 1f 44 00 00 b8 59 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 8b 15 21 ba 0d 00 f7 d8 64 89 02 48
RSP: 002b:00007fff013824c8 EFLAGS: 00000206 ORIG_RAX: 0000000000000059
RAX: ffffffffffffffda RBX: 00007fff01382d10 RCX: 00007f7f68b153a7
RDX: 0000000000000400 RSI: 00007fff013828d0 RDI: 00007fff013824d0
RBP: 0000000000000200 R08: 00005602e52d2c29 R09: 0000000000000000
R10: 0000000000000040 R11: 0000000000000206 R12: 00007fff013824d0
R13: 00007fff013828d0 R14: 0000000000000000 R15: 00007fff01383220