INFO: task syz.0.1163:11227 blocked for more than 143 seconds.
Tainted: G U L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1163 state:D stack:28792 pid:11227 tgid:11223 ppid:5823 task_flags:0x480040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0xfee/0x6120 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7008
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
blk_debugfs_lock block/blk.h:752 [inline]
blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
blk_trace_ioctl+0x245/0x320 kernel/trace/blktrace.c:937
blkdev_ioctl+0x17c/0x6f0 block/ioctl.c:793
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f72ec19c799
RSP: 002b:00007f72ecf86028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f72ec416090 RCX: 00007f72ec19c799
RDX: 00002000000000c0 RSI: 00000000c0481273 RDI: 0000000000000004
RBP: 00007f72ec232c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f72ec416128 R14: 00007f72ec416090 R15: 00007ffc3177e658
INFO: task syz.0.1163:11229 blocked for more than 145 seconds.
Tainted: G U L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1163 state:D stack:29000 pid:11229 tgid:11223 ppid:5823 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0xfee/0x6120 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7008
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
blk_trace_remove kernel/trace/blktrace.c:561 [inline]
blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
blkdev_common_ioctl+0x170c/0x2ba0 block/ioctl.c:724
blkdev_ioctl+0x43b/0x6f0 block/ioctl.c:798
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f72ec19c799
RSP: 002b:00007f72ea3f6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f72ec416180 RCX: 00007f72ec19c799
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000004
RBP: 00007f72ec232c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f72ec416218 R14: 00007f72ec416180 R15: 00007ffc3177e658
Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
#0: ffffffff8e7f3278 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
1 lock held by khungtaskd/31:
#0: ffffffff8e7e7660 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7e7660 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7e7660 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
3 locks held by kworker/1:3/1860:
#0: ffff88813fe63148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
#1: ffffc90005c17d08 ((fqdir_free_work).work){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
#2: ffffffff8e7f3140 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6d0 kernel/rcu/tree.c:3828
2 locks held by kworker/1:4/1871:
#0: ffff88813fe63148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
#1: ffffc900056afd08 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
3 locks held by kworker/u8:12/8452:
#0: ffff88801c6ae948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
#1: ffffc9000486fd08 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
#2: ffffffff8e7f3140 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6d0 kernel/rcu/tree.c:3828
6 locks held by kworker/u8:13/8453:
3 locks held by kworker/u8:17/8464:
#0: ffff88813fea4148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
#1: ffffc90004997d08 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
#2: ffffffff906145e8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:313
4 locks held by kworker/u8:38/10690:
5 locks held by kworker/u8:43/10697:
#0: ffff8880b843b2e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:655 [inline]
#0: ffff8880b843b2e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x88/0x140 kernel/sched/core.c:639
#1: ffffc9000391fd08 ((work_completion)(&cp->cp_down_w)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
#2: ffff88808a2681e0 (k-slock-AF_INET){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:347 [inline]
#2: ffff88808a2681e0 (k-slock-AF_INET){+.-.}-{3:3}, at: release_sock+0x21/0x220 net/core/sock.c:3793
#3: ffffffff8e7e7660 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#3: ffffffff8e7e7660 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#3: ffffffff8e7e7660 (rcu_read_lock){....}-{1:3}, at: __ip_queue_xmit+0x69/0x1e90 net/ipv4/ip_output.c:477
#4: ffffffff94122448 (pvclock_gtod_data){-.-.}-{0:0}, at: notifier_call_chain+0x99/0x420 kernel/notifier.c:85
2 locks held by syz.1.1152/11180:
1 lock held by syz.0.1163/11227:
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:752 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
1 lock held by syz.0.1163/11229:
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
1 lock held by syz.2.1170/11261:
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:752 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
1 lock held by syz.2.1170/11262:
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
1 lock held by syz.5.1178/11430:
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:752 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
1 lock held by syz.5.1178/11431:
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
1 lock held by syz.3.1205/11472:
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:752 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
1 lock held by syz.3.1205/11473:
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
1 lock held by syz.6.1213/11505:
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:752 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
1 lock held by syz.6.1213/11506:
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff8880265c5520 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
1 lock held by syz-executor/11598:
#0: ffffffff906145e8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff906145e8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
1 lock held by syz.8.1334/12131:
#0: ffffffff906145e8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff906145e8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
1 lock held by syz.4.1356/12239:
#0: ffffffff906145e8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff906145e8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
1 lock held by syz.7.1368/12299:
#0: ffffffff906145e8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff906145e8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G U L syzkaller #0 PREEMPT(full)
Tainted: [U]=USER, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x1d7/0x230 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+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xd25/0x1050 kernel/hung_task.c:515
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x754/0xd80 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: 8453 Comm: kworker/u8:13 Tainted: G U L syzkaller #0 PREEMPT(full)
Tainted: [U]=USER, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: krds_cp_wq#2/0 rds_shutdown_worker
RIP: 0010:stack_access_ok+0xc/0x1d0 arch/x86/kernel/unwind_orc.c:405
Code: 41 5f 5d e9 96 fe d8 09 e8 71 cb d5 09 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 48 b8 00 00 00 00 00 fc ff df 41 55 <41> 54 49 89 d4 48 89 fa 55 48 c1 ea 03 48 89 f5 53 48 89 fb 48 83
RSP: 0018:ffffc90000a08458 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffffff9212191c
RDX: 0000000000000008 RSI: ffffc900043f79d0 RDI: ffffc90000a084d8
RBP: ffffc90000a08520 R08: ffffffff92121920 R09: 0000000000000007
R10: 0000000000000200 R11: 000000000008fa94 R12: ffffc90000a08528
R13: ffffc90000a084d8 R14: ffffc900043f79d8 R15: ffffc90000a0850c
FS: 0000000000000000(0000) GS:ffff888124449000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f425b1e6e9c CR3: 0000000033b4a000 CR4: 00000000003526f0
Call Trace:
deref_stack_reg arch/x86/kernel/unwind_orc.c:419 [inline]
unwind_next_frame+0xb0b/0x1ea0 arch/x86/kernel/unwind_orc.c:600
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
slab_free_hook mm/slub.c:2646 [inline]
slab_free mm/slub.c:6165 [inline]
kmem_cache_free+0x434/0x6a0 mm/slub.c:6295
sk_prot_free net/core/sock.c:2282 [inline]
__sk_destruct+0x649/0xbb0 net/core/sock.c:2384
sk_destruct+0xc8/0xf0 net/core/sock.c:2412
__sk_free+0xf4/0x3e0 net/core/sock.c:2423
sk_free+0x61/0x90 net/core/sock.c:2434
sock_put include/net/sock.h:2007 [inline]
tcp_v4_rcv+0x2e6b/0x4680 net/ipv4/tcp_ipv4.c:2328
ip_protocol_deliver_rcu+0xba/0x4d0 net/ipv4/ip_input.c:207
ip_local_deliver_finish+0x3f2/0x6e0 net/ipv4/ip_input.c:241
NF_HOOK include/linux/netfilter.h:318 [inline]
NF_HOOK include/linux/netfilter.h:312 [inline]
ip_local_deliver+0x19a/0x1f0 net/ipv4/ip_input.c:262
dst_input include/net/dst.h:480 [inline]
ip_rcv_finish net/ipv4/ip_input.c:453 [inline]
NF_HOOK include/linux/netfilter.h:318 [inline]
NF_HOOK include/linux/netfilter.h:312 [inline]
ip_rcv+0x33a/0x3c0 net/ipv4/ip_input.c:573
__netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:6164
__netif_receive_skb+0x1f/0x120 net/core/dev.c:6277
process_backlog+0x37a/0x1580 net/core/dev.c:6628
__napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7692
napi_poll net/core/dev.c:7755 [inline]
net_rx_action+0xa40/0xf20 net/core/dev.c:7912
handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622
do_softirq kernel/softirq.c:523 [inline]
do_softirq+0xac/0xe0 kernel/softirq.c:510
__local_bh_enable_ip+0xf8/0x120 kernel/softirq.c:450
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:924 [inline]
__dev_queue_xmit+0x8b5/0x4800 net/core/dev.c:4873
dev_queue_xmit include/linux/netdevice.h:3385 [inline]
neigh_hh_output include/net/neighbour.h:540 [inline]
neigh_output include/net/neighbour.h:554 [inline]
ip_finish_output2+0xf4a/0x24d0 net/ipv4/ip_output.c:237
__ip_finish_output.part.0+0x444/0x6f0 net/ipv4/ip_output.c:315
__ip_finish_output net/ipv4/ip_output.c:303 [inline]
ip_finish_output net/ipv4/ip_output.c:325 [inline]
NF_HOOK_COND include/linux/netfilter.h:307 [inline]
ip_output+0x39b/0xc10 net/ipv4/ip_output.c:438
dst_output include/net/dst.h:470 [inline]
ip_local_out+0x193/0x1f0 net/ipv4/ip_output.c:131
__ip_queue_xmit+0x885/0x1e90 net/ipv4/ip_output.c:534
__tcp_transmit_skb+0x3347/0x4b50 net/ipv4/tcp_output.c:1693
tcp_transmit_skb net/ipv4/tcp_output.c:1711 [inline]
tcp_write_xmit+0x12a2/0x8980 net/ipv4/tcp_output.c:3064
__tcp_push_pending_frames+0xaf/0x3b0 net/ipv4/tcp_output.c:3247
tcp_send_fin+0x11f/0x10f0 net/ipv4/tcp_output.c:3846
tcp_shutdown+0x101/0x130 net/ipv4/tcp.c:3122
inet_shutdown+0x1a5/0x410 net/ipv4/af_inet.c:937
rds_tcp_conn_path_shutdown+0x23a/0x970 net/rds/tcp_connect.c:248
rds_conn_shutdown+0x478/0xc20 net/rds/connection.c:414
process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
process_scheduled_works kernel/workqueue.c:3359 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245