INFO: task syz.2.227:7721 blocked for more than 143 secon[ 500.337395][ T38] INFO: task syz.2.227:7721 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.227 state:D stack:26840 pid:7721 tgid:7720 ppid:7502 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0x1472/0x4fe0 kernel/sched/core.c:6867
__schedule_loop kernel/sched/core.c:6949 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7245
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
__rwbase_read_lock+0xc3/0x180 kernel/locking/rwbase_rt.c:114
rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline]
__down_read kernel/locking/rwsem.c:1466 [inline]
down_read+0x132/0x200 kernel/locking/rwsem.c:1539
__super_lock fs/super.c:59 [inline]
super_lock+0x2d6/0x3d0 fs/super.c:121
user_get_super+0xc8/0x120 fs/super.c:998
quotactl_block fs/quota/quota.c:890 [inline]
__do_sys_quotactl fs/quota/quota.c:955 [inline]
__se_sys_quotactl+0x516/0x990 fs/quota/quota.c:917
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa68a6faeb9
RSP: 002b:00007fa688956028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fa68a975fa0 RCX: 00007fa68a6faeb9
RDX: 0000000000000000 RSI: 0000200000002540 RDI: ffffffff80000800
RBP: 00007fa68a768c1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000140 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa68a976038 R14: 00007fa68a975fa0 R15: 00007fff1c9c9f68
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8dbc77c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8dbc77c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8dbc77c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
6 locks held by kworker/u8:11/3093:
#0: ffff88801aad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88801aad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
#1: ffffc9000da97bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000da97bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
#2: ffffffff8ef2caa0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xfe/0x7b0 net/core/net_namespace.c:670
#3: ffff888061ffc0d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#3: ffff888061ffc0d8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline]
#3: ffff888061ffc0d8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x117/0x3f0 net/devlink/core.c:506
#4: ffff88805e4a0300 (&devlink->lock_key#25){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline]
#4: ffff88805e4a0300 (&devlink->lock_key#25){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline]
#4: ffff88805e4a0300 (&devlink->lock_key#25){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x129/0x3f0 net/devlink/core.c:506
#5: ffffffff8dbcdff0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3816
4 locks held by udevd/5169:
2 locks held by getty/5555:
#0: ffff88803508d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e7b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
3 locks held by syz-executor/5803:
6 locks held by kworker/0:8/5924:
2 locks held by syz-executor/7574:
#0: ffff888056c2c0d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff888056c2c0d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff888056c2c0d0 (&type->s_umount_key#59){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
#1: ffff88805ec24888 (&ailp->ail_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
#1: ffff88805ec24888 (&ailp->ail_lock){+.+.}-{3:3}, at: xfs_ail_push_all_sync+0x1e1/0x2b0 fs/xfs/xfs_trans_ail.c:722
1 lock held by syz.2.227/7721:
#0: ffff888039e720d0 (&type->s_umount_key#65){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff888039e720d0 (&type->s_umount_key#65){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:121
1 lock held by syz-executor/7728:
3 locks held by syz-executor/9173:
3 locks held by syz.9.398/9195:
1 lock held by syz.0.399/9198:
#0: ffff88803961a0d0 (&type->s_umount_key#56/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xab0 fs/super.c:344
1 lock held by sed/9206:
=============================================
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 01/24/2026
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+0xf90/0xfe0 kernel/hung_task.c:515
kthread+0x726/0x8b0 kernel/kthread.c:463
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 9173 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:103 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:238 [inline]
RIP: 0010:unwind_next_frame+0x524/0x23c0 arch/x86/kernel/unwind_orc.c:510
Code: 00 49 01 ef 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 27 49 63 07 4c 01 f8 49 8d 4f 04 4c 39 e0 <48> 0f 46 e9 49 8d 47 fc 48 0f 47 d8 4d 0f 46 ef 48 39 dd 76 a2 e9
RSP: 0018:ffffc900055a6778 EFLAGS: 00000283
RAX: ffffffff81759a3f RBX: ffffffff8f5ebdcc RCX: ffffffff8f5ebdd0
RDX: ffffffff8f5ebdac RSI: ffffffff8fd41350 RDI: ffffffff8b85e820
RBP: ffffffff8f5ebdcc R08: 0000000000000009 R09: ffffffff8dbc77c0
R10: ffffc900055a68a8 R11: fffff52000ab4d21 R12: ffffffff81759a56
R13: ffffffff8f5ebdc8 R14: ffffc900055a68a8 R15: ffffffff8f5ebdcc
FS: 000055556363f500(0000) GS:ffff8881266c9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f942e439368 CR3: 00000000695ea000 CR4: 00000000003526f0
Call Trace:
__unwind_start+0x5b8/0x760 arch/x86/kernel/unwind_orc.c:773
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_node_noprof+0x22f/0x6d0 mm/slub.c:5315
__alloc_skb+0x1d7/0x390 net/core/skbuff.c:679
alloc_skb include/linux/skbuff.h:1383 [inline]
nlmsg_new include/net/netlink.h:1055 [inline]
inet6_ifmcaddr_notify+0xfa/0x1e0 net/ipv6/mcast.c:909
__ipv6_dev_mc_inc+0x8a9/0xa50 net/ipv6/mcast.c:973
ipv6_add_dev+0xe72/0x1400 net/ipv6/addrconf.c:472
addrconf_notify+0x771/0x1050 net/ipv6/addrconf.c:3650
notifier_call_chain+0x19d/0x3a0 kernel/notifier.c:85
call_netdevice_notifiers_extack net/core/dev.c:2281 [inline]
call_netdevice_notifiers net/core/dev.c:2295 [inline]
register_netdevice+0x1731/0x1cf0 net/core/dev.c:11444
br_dev_newlink+0x6d/0x170 net/bridge/br_netlink.c:1565
rtnl_newlink_create+0x329/0xb70 net/core/rtnetlink.c:3840
__rtnl_newlink net/core/rtnetlink.c:3957 [inline]
rtnl_newlink+0x1666/0x1be0 net/core/rtnetlink.c:4072
rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6958
netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x831/0x9f0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
__sys_sendto+0x72a/0x7d0 net/socket.c:2206
__do_sys_sendto net/socket.c:2213 [inline]
__se_sys_sendto net/socket.c:2209 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2209
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9f7945b78e
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:00007ffde1853938 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000055556363f500 RCX: 00007f9f7945b78e
RDX: 000000000000004c RSI: 00007f9f7a244670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffde18539b4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f9f7a244670 R15: 0000000000000000