syzbot

INFO: task kworker/u8:8:3028 blocked for more than 143 seconds.
      Not tainted 6.14.0-rc7-syzkaller-00074-ga7f2e10ecd8f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:8    state:D stack:19896 pid:3028  tgid:3028  ppid:2      task_flags:0x4208060 flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0x18bc/0x4c40 kernel/sched/core.c:6765
 __schedule_loop kernel/sched/core.c:6842 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6857
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914
 __mutex_lock_common kernel/locking/mutex.c:662 [inline]
 __mutex_lock+0x817/0x1010 kernel/locking/mutex.c:730
 rdma_dev_change_netns+0x3a/0x2f0 drivers/infiniband/core/device.c:1650
 rdma_dev_exit_net+0x21e/0x350 drivers/infiniband/core/device.c:1135
 ops_exit_list net/core/net_namespace.c:172 [inline]
 cleanup_net+0x812/0xd60 net/core/net_namespace.c:652
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd30 kernel/workqueue.c:3400
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
INFO: task syz.4.6349:19203 blocked for more than 143 seconds.
      Not tainted 6.14.0-rc7-syzkaller-00074-ga7f2e10ecd8f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.6349      state:D stack:22256 pid:19203 tgid:19202 ppid:5823   task_flags:0x400140 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0x18bc/0x4c40 kernel/sched/core.c:6765
 __schedule_loop kernel/sched/core.c:6842 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6857
 schedule_timeout+0xb0/0x290 kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common kernel/sched/completion.c:116 [inline]
 wait_for_common kernel/sched/completion.c:127 [inline]
 wait_for_completion+0x355/0x620 kernel/sched/completion.c:148
 disable_device+0x1c7/0x360 drivers/infiniband/core/device.c:1279
 __ib_unregister_device+0x2ac/0x3d0 drivers/infiniband/core/device.c:1502
 ib_unregister_device_and_put+0xb9/0xf0 drivers/infiniband/core/device.c:1567
 nldev_dellink+0x2c6/0x310 drivers/infiniband/core/nldev.c:1825
 rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
 rdma_nl_rcv+0x6dd/0x9e0 drivers/infiniband/core/netlink.c:259
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1882
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:733
 ____sys_sendmsg+0x53a/0x860 net/socket.c:2573
 ___sys_sendmsg net/socket.c:2627 [inline]
 __sys_sendmsg+0x269/0x350 net/socket.c:2659
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcac558d169
RSP: 002b:00007fcac64d5038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fcac57a5fa0 RCX: 00007fcac558d169
RDX: 0000000000040080 RSI: 0000200000000540 RDI: 0000000000000003
RBP: 00007fcac560e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fcac57a5fa0 R15: 00007ffe88bf96d8
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/1:0/26:
 #0: ffff88801e697948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88801e697948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319
 #1: ffffc90000a0fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc90000a0fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319
 #2: ffff888145f1a190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline]
 #2: ffff888145f1a190 (&dev->mutex){....}-{4:4}, at: hub_event+0x1fe/0x5150 drivers/usb/core/hub.c:5861
1 lock held by khungtaskd/31:
 #0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746
2 locks held by kworker/u8:7/2959:
4 locks held by kworker/u8:8/3028:
 #0: ffff88801bef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88801bef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319
 #1: ffffc9000bfb7c60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc9000bfb7c60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319
 #2: ffffffff8feb7410 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17a/0xd60 net/core/net_namespace.c:606
 #3: ffff888079de46c0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x3a/0x2f0 drivers/infiniband/core/device.c:1650
2 locks held by getty/5582:
 #0: ffff8880359ca0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211
2 locks held by syz.4.6349/19203:
 #0: ffffffff9a9dc958 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:164 [inline]
 #0: ffffffff9a9dc958 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
 #0: ffffffff9a9dc958 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv+0x32d/0x9e0 drivers/infiniband/core/netlink.c:259
 #1: ffff888079de46c0 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x264/0x3d0 drivers/infiniband/core/device.c:1498

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-rc7-syzkaller-00074-ga7f2e10ecd8f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
 watchdog+0x1058/0x10a0 kernel/hung_task.c:399
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 75 Comm: kworker/u8:4 Not tainted 6.14.0-rc7-syzkaller-00074-ga7f2e10ecd8f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__lock_acquire+0x11d/0x2100 kernel/locking/lockdep.c:5125
Code: 48 be 00 00 00 00 00 fc ff df 48 89 c3 48 85 c0 0f 84 1a 13 00 00 49 8d bc 24 e8 0a 00 00 48 89 f8 48 c1 e8 03 48 89 44 24 30 <0f> b6 04 30 84 c0 48 89 3c 24 0f 85 4c 16 00 00 8b 17 48 c7 c0 80
RSP: 0018:ffffc900015a7850 EFLAGS: 00000802
RAX: 1ffff1100455915d RBX: ffffffff93e910c8 RCX: 0000000000000001
RDX: ffffffff94087700 RSI: dffffc0000000000 RDI: ffff888022ac8ae8
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff2077a0f R12: ffff888022ac8000
R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff8eb393e0
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2fe0eff8 CR3: 0000000033f36000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
 rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 rcu_read_lock include/linux/rcupdate.h:849 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
 batadv_nc_worker+0xec/0x610 net/batman-adv/network-coding.c:719
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd30 kernel/workqueue.c:3400
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>