INFO: task syz.1.77:6237 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.77 state:D stack:28056 pid:6237 tgid:6236 ppid:5842 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7339
rt_mutex_slowlock_block+0x5ba/0x6d0 kernel/locking/rtmutex.c:1647
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline]
rt_mutex_slowlock+0x2b1/0x6e0 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:536 [inline]
mutex_lock_nested+0x16a/0x1d0 kernel/locking/rtmutex_api.c:547
bdev_open+0xe0/0xcc0 block/bdev.c:945
blkdev_open+0x3bd/0x520 block/fops.c:691
do_dentry_open+0x9ae/0x1350 fs/open.c:965
vfs_open+0x3b/0x350 fs/open.c:1095
do_open fs/namei.c:3887 [inline]
path_openat+0x2ef1/0x3840 fs/namei.c:4046
do_filp_open+0x1fa/0x410 fs/namei.c:4073
do_sys_openat2+0x121/0x1c0 fs/open.c:1435
do_sys_open fs/open.c:1450 [inline]
__do_sys_openat fs/open.c:1466 [inline]
__se_sys_openat fs/open.c:1461 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1461
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa188ded550
RSP: 002b:00007fa187055b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fa188ded550
RDX: 0000000000000000 RSI: 00007fa187055c10 RDI: 00000000ffffff9c
RBP: 00007fa187055c10 R08: 0000000000000000 R09: 002364626e2f7665
R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd
R13: 00007fa189016038 R14: 00007fa189015fa0 R15: 00007fffa706da18
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8d9a8b80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d9a8b80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8d9a8b80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:8/1221:
#0: ffff88814d08f138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88814d08f138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc900052bfbc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc900052bfbc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffffffff8ecd1e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8ecd1e78 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x119/0x15a0 net/ipv6/addrconf.c:4194
2 locks held by kworker/u8:11/1417:
2 locks held by dhcpcd/5500:
#0: ffff888039424908 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2406
#1: ffffffff8ecd1e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8ecd1e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6814
2 locks held by getty/5594:
#0: ffff88823bf3c0a0 (&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+0x444/0x1410 drivers/tty/n_tty.c:2222
1 lock held by udevd/5887:
#0: ffff888024e664c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
1 lock held by udevd/5894:
#0: ffff888024c5e4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
3 locks held by kworker/1:5/5922:
#0: ffff888019898538 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff888019898538 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc9000551fbc0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc9000551fbc0 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffffffff8ecd1e78 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
1 lock held by udevd/5969:
#0: ffff888024d8a4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
1 lock held by udevd/5987:
#0: ffff88802564e4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
1 lock held by udevd/5988:
#0: ffff888024e7e4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
1 lock held by udevd/5989:
#0: ffff88803ae964c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
1 lock held by udevd/5999:
#0: ffff888024fae4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
1 lock held by udevd/6038:
#0: ffff8880256564c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
1 lock held by udevd/6162:
#0: ffff8880256524c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
1 lock held by udevd/6194:
#0: ffff8880254fe4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
1 lock held by udevd/6199:
#0: ffff8880255524c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
1 lock held by udevd/6201:
#0: ffff88802550e4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
3 locks held by kworker/0:8/6223:
1 lock held by syz.1.77/6237:
#0: ffff888024d8a4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
3 locks held by kworker/u8:15/6376:
#0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc9000b9a7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc9000b9a7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffffffff8ecd1e78 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
1 lock held by syz.2.128/6422:
#0: ffff888024e664c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
4 locks held by kworker/u8:19/6712:
2 locks held by syz-executor/6915:
#0: ffffffff8e43a940 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e43a940 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e43a940 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8ecd1e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8ecd1e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8ecd1e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056
2 locks held by syz-executor/7020:
#0: ffffffff8ecc4f80 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:566
#1: ffffffff8ecd1e78 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2ab/0x800 net/ipv4/ip_tunnel.c:1160
3 locks held by syz.4.283/7113:
#0: ffffffff8ed37e80 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffff88803852e908 (nlk_cb_mutex-GENERIC){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2406
#2: ffffffff8ecd1e78 (rtnl_mutex){+.+.}-{4:4}, at: nl80211_dump_wiphy+0x49/0x6f0 net/wireless/nl80211.c:3233
1 lock held by syz.0.284/7118:
#0: ffff888036b84098 (&u->peer_wait){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
#0: ffff888036b84098 (&u->peer_wait){+.+.}-{3:3}, at: finish_wait+0xbf/0x1f0 kernel/sched/wait.c:394
2 locks held by syz.0.284/7119:
3 locks held by syz.0.284/7120:
#0: ffff888036b83fe8 (&u->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
#0: ffff888036b83fe8 (&u->lock){+.+.}-{3:3}, at: unix_dgram_sendmsg+0x90e/0x1850 net/unix/af_unix.c:2200
#1: ffffffff8d9a8b80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#1: ffffffff8d9a8b80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#1: ffffffff8d9a8b80 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#1: ffffffff8d9a8b80 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1bb/0x2c0 kernel/locking/spinlock_rt.c:57
#2: ffff888036b84098 (&u->peer_wait){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
#2: ffff888036b84098 (&u->peer_wait){+.+.}-{3:3}, at: prepare_to_wait_exclusive+0x44/0x230 kernel/sched/wait.c:269
=============================================
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 07/12/2025
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:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
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: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 53 b2 03 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 53 f3 11 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc900001d7de0 EFLAGS: 000002c6
RAX: 42d66cde9d5a2600 RBX: ffffffff81954f08 RCX: 42d66cde9d5a2600
RDX: 0000000000000001 RSI: ffffffff8d0384e3 RDI: ffffffff8b620c80
RBP: ffffc900001d7f20 R08: ffff8880b893341b R09: 1ffff11017126683
R10: dffffc0000000000 R11: ffffed1017126684 R12: ffffffff8f1d4430
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110038dfb28
FS: 0000000000000000(0000) GS:ffff8881269c2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000005e030 CR3: 000000003dda6000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:757
default_idle_call+0x74/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x1e8/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x147