syzbot


INFO: task hung in vhost_worker_killed

Status: auto-obsoleted due to no activity on 2024/12/17 14:09
Subsystems: kvm net virt
[Documentation on labels]
First crash: 124d, last: 124d

Sample crash report:
INFO: task vhost-12138:12139 blocked for more than 143 seconds.
      Not tainted 6.11.0-syzkaller-04557-g2f27fce67173 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:vhost-12138     state:D stack:28760 pid:12139 tgid:12136 ppid:11405  flags:0x20004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x1800/0x4a60 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752
 vhost_worker_killed+0x127/0x390 drivers/vhost/vhost.c:429
 vhost_task_fn+0x39d/0x3f0 kernel/vhost_task.c:62
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
INFO: task syz.1.1452:12162 blocked for more than 144 seconds.
      Not tainted 6.11.0-syzkaller-04557-g2f27fce67173 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1452      state:D stack:23680 pid:12162 tgid:12136 ppid:11405  flags:0x20004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x1800/0x4a60 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752
 vhost_vsock_dev_ioctl+0x2a6/0xf90 drivers/vhost/vsock.c:876
 __do_compat_sys_ioctl fs/ioctl.c:1007 [inline]
 __se_compat_sys_ioctl+0x510/0xc90 fs/ioctl.c:950
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f70579
RSP: 002b:00000000f56b456c EFLAGS: 00000206 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000004008af10
RDX: 0000000020000280 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
7 locks held by kworker/1:0/25:
1 lock held by khungtaskd/30:
 #0: ffffffff8e938a60
 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6701
3 locks held by kworker/u8:6/1275:
 #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc9000452fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc9000452fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffffffff8fcc2948 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276
5 locks held by kworker/u8:7/2560:
5 locks held by kworker/u8:8/2920:
 #0: ffff88801bae5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff88801bae5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc90009817d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc90009817d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffffffff8fcb5e50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580
 #3: ffffffff8fcc2948 (rtnl_mutex){+.+.}-{3:3}, at: cleanup_net+0x6af/0xcc0 net/core/net_namespace.c:616
 #4: ffffffff8e93de38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline]
 #4: ffffffff8e93de38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:965
2 locks held by dhcpcd/4894:
 #0: ffffffff8fd28670 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffffffff8fcc2948 (rtnl_mutex){+.+.}-{3:3}, at: nl80211_pre_doit+0x5f/0x8b0 net/wireless/nl80211.c:16580
2 locks held by getty/4986:
 #0: ffff88802fdd40a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900031232f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
4 locks held by kworker/1:3/5261:
 #0: ffff88801de8f948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff88801de8f948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc90003f07d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc90003f07d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffff888029131190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline]
 #2: ffff888029131190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1fe/0x5150 drivers/usb/core/hub.c:5849
 #3: ffff888029160518 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3206 [inline]
 #3: ffff888029160518 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x7d5/0x5150 drivers/usb/core/hub.c:5902
2 locks held by kworker/0:3/5276:
 #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc90004277d00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc90004277d00 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
3 locks held by kworker/0:6/5312:
 #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc90004387d00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc90004387d00 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffffffff8fcc2948 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
1 lock held by syz.1.1452/12138:
3 locks held by vhost-12138/12139:
 #0: ffff88807cbc04e8
 (&vtsk->exit_mutex
){+.+.}-{3:3}, at: vhost_task_fn+0x2f3/0x3f0 kernel/vhost_task.c:54
 #1: ffff888065263078 (&worker->mutex){+.+.}-{3:3}, at: vhost_worker_killed+0x57/0x390 drivers/vhost/vhost.c:423
 #2: ffff88804b840258 (&vq->mutex){+.+.}-{3:3}, at: vhost_worker_killed+0x127/0x390 drivers/vhost/vhost.c:429
4 locks held by syz.1.1452/12158:
1 lock held by syz.1.1452/12162:
 #0: ffff88804b840070 (&dev->mutex#5){+.+.}-{3:3}, at: vhost_vsock_dev_ioctl+0x2a6/0xf90 drivers/vhost/vsock.c:876
4 locks held by syz.0.1856/14079:
 #0: ffff888069920d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline]
 #0: ffff888069920d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2698
 #1: ffff888069920078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x572/0x11a0 net/bluetooth/hci_sync.c:5183
 #2: ffffffff8fe2f0e8
 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1972 [inline]
 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2589
 #3: ffffffff8e93de38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline]
 #3: ffffffff8e93de38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:965
1 lock held by syz-executor/14085:
 #0: ffffffff8fcc2948 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffffffff8fcc2948 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-04557-g2f27fce67173 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 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:223 [inline]
 watchdog+0xff4/0x1040 kernel/hung_task.c:379
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 35 Comm: kworker/u8:2 Not tainted 6.11.0-syzkaller-04557-g2f27fce67173 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:get_stack_info+0x85/0xf0 arch/x86/kernel/dumpstack_64.c:221
Code: 48 8b 04 25 80 d4 03 00 48 39 c5 75 09 80 3d 13 33 d2 0e 00 74 1e c7 03 00 00 00 00 41 bf ea ff ff ff 44 89 f8 5b 41 5c 41 5d <41> 5e 41 5f 5d c3 cc cc cc cc c6 05 ec 32 d2 0e 01 8b 33 48 c7 c7
RSP: 0018:ffffc90000ab7540 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffffc90000ab7560 RCX: 0000000000000001
RDX: ffffc90000ab75c0 RSI: ffffc90000ab8000 RDI: ffffc90000ab7560
RBP: ffff888020e9da00 R08: ffffc90000ab7601 R09: 0000000000000000
R10: ffffc90000ab75c0 R11: fffff52000156ec4 R12: ffffc90000ab75e0
R13: ffffc90000ab75e8 R14: ffffc90000ab75e0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200016c0 CR3: 000000000e734000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 000000000000000a DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 __unwind_start+0x434/0x740 arch/x86/kernel/unwind_orc.c:729
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0xe5/0x150 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240
 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2250 [inline]
 slab_free mm/slub.c:4474 [inline]
 kmem_cache_free+0x145/0x350 mm/slub.c:4549
 skb_kfree_head net/core/skbuff.c:1084 [inline]
 skb_free_head net/core/skbuff.c:1098 [inline]
 skb_release_data+0x677/0x8a0 net/core/skbuff.c:1125
 skb_release_all net/core/skbuff.c:1190 [inline]
 __kfree_skb net/core/skbuff.c:1204 [inline]
 sk_skb_reason_drop+0x1c9/0x380 net/core/skbuff.c:1242
 kfree_skb_reason include/linux/skbuff.h:1262 [inline]
 kfree_skb include/linux/skbuff.h:1271 [inline]
 ieee80211_iface_work+0x272/0xf20 net/mac80211/iface.c:1659
 cfg80211_wiphy_work+0x2db/0x490 net/wireless/core.c:440
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x870/0xd30 kernel/workqueue.c:3393
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/18 14:08 upstream 2f27fce67173 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: task hung in vhost_worker_killed
* Struck through repros no longer work on HEAD.