syzbot


INFO: task hung in cfg80211_dfs_channels_update_work (4)

Status: auto-closed as invalid on 2022/09/24 17:02
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 162d, last: 162d
similar bugs (5):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in cfg80211_dfs_channels_update_work (2) 1 324d 324d 0/1 auto-closed as invalid on 2022/05/15 07:22
upstream INFO: task hung in cfg80211_dfs_channels_update_work 1 800d 800d 0/24 auto-closed as invalid on 2020/12/24 22:54
upstream INFO: task hung in cfg80211_dfs_channels_update_work (2) 3 649d 705d 0/24 auto-closed as invalid on 2021/05/25 10:38
linux-4.19 INFO: task hung in cfg80211_dfs_channels_update_work 1 450d 450d 0/1 auto-closed as invalid on 2022/01/09 14:58
upstream INFO: task hung in cfg80211_dfs_channels_update_work (3) 18 341d 554d 0/24 closed as invalid on 2022/02/07 19:19

Sample crash report:
INFO: task kworker/u4:4:92 blocked for more than 143 seconds.
      Not tainted 5.19.0-rc3-syzkaller-00573-gebeae54d3a77 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:4    state:D stack:24392 pid:   92 ppid:     2 flags:0x00004000
Workqueue: cfg80211 cfg80211_dfs_channels_update_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5146 [inline]
 __schedule+0xa00/0x4b50 kernel/sched/core.c:6458
 schedule+0xd2/0x1f0 kernel/sched/core.c:6530
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6589
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0xa70/0x1350 kernel/locking/mutex.c:747
 cfg80211_dfs_channels_update_work+0x91/0x5f0 net/wireless/mlme.c:844
 process_one_work+0x996/0x1610 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
 </TASK>
INFO: task dhcpcd:3188 blocked for more than 143 seconds.
      Not tainted 5.19.0-rc3-syzkaller-00573-gebeae54d3a77 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:dhcpcd          state:D stack:26144 pid: 3188 ppid:     1 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5146 [inline]
 __schedule+0xa00/0x4b50 kernel/sched/core.c:6458
 schedule+0xd2/0x1f0 kernel/sched/core.c:6530
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6589
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0xa70/0x1350 kernel/locking/mutex.c:747
 vlan_ioctl_handler+0xb7/0xec0 net/8021q/vlan.c:553
 sock_ioctl+0x1d8/0x640 net/socket.c:1250
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7fcbaf68c0e7
RSP: 002b:00007ffe34f995a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000055a98f6a9420 RCX: 00007fcbaf68c0e7
RDX: 00007ffe34f995b0 RSI: 0000000000008982 RDI: 0000000000000011
RBP: 0000000000000002 R08: 0000000000000008 R09: 0000000000000000
R10: 00007ffe34fa9c20 R11: 0000000000000246 R12: 00007ffe34f995b0
R13: 00007ffe34f99670 R14: 000055a98f6a9420 R15: 000055a98f81c5f0
 </TASK>
INFO: task kworker/0:3:18230 blocked for more than 143 seconds.
      Not tainted 5.19.0-rc3-syzkaller-00573-gebeae54d3a77 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:3     state:D stack:26104 pid:18230 ppid:     2 flags:0x00004000
Workqueue: events linkwatch_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5146 [inline]
 __schedule+0xa00/0x4b50 kernel/sched/core.c:6458
 schedule+0xd2/0x1f0 kernel/sched/core.c:6530
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6589
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0xa70/0x1350 kernel/locking/mutex.c:747
 linkwatch_event+0xb/0x60 net/core/link_watch.c:263
 process_one_work+0x996/0x1610 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
 </TASK>
INFO: task syz-executor.5:23422 blocked for more than 143 seconds.
      Not tainted 5.19.0-rc3-syzkaller-00573-gebeae54d3a77 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5  state:D stack:25248 pid:23422 ppid:     1 flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5146 [inline]
 __schedule+0xa00/0x4b50 kernel/sched/core.c:6458
 schedule+0xd2/0x1f0 kernel/sched/core.c:6530
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6589
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0xa70/0x1350 kernel/locking/mutex.c:747
 rtnl_lock net/core/rtnetlink.c:74 [inline]
 rtnetlink_rcv_msg+0x3e5/0xc90 net/core/rtnetlink.c:6086
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2501
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x917/0xe10 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:734
 __sys_sendto+0x21a/0x320 net/socket.c:2116
 __do_sys_sendto net/socket.c:2128 [inline]
 __se_sys_sendto net/socket.c:2124 [inline]
 __x64_sys_sendto+0xdd/0x1b0 net/socket.c:2124
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7f7c8c43becc
RSP: 002b:00007fffb6440720 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f7c8d4d4320 RCX: 00007f7c8c43becc
RDX: 0000000000000028 RSI: 00007f7c8d4d4370 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007fffb6440774 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007f7c8d4d4370 R14: 0000000000000003 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
2 locks held by pr/ttyS0/16:
1 lock held by khungtaskd/29:
 #0: ffffffff8bd86ba0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6491
3 locks held by kworker/u4:4/92:
 #0: ffff8880177fb138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff8880177fb138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff8880177fb138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff8880177fb138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline]
 #0: ffff8880177fb138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
 #0: ffff8880177fb138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260
 #1: ffffc900015f7da8 ((work_completion)(&(&rdev->dfs_update_channels_wk)->work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264
 #2: ffffffff8d5911a8 (rtnl_mutex){+.+.}-{3:3}, at: cfg80211_dfs_channels_update_work+0x91/0x5f0 net/wireless/mlme.c:844
2 locks held by dhcpcd/3188:
 #0: ffffffff8d56da68 (vlan_ioctl_mutex){+.+.}-{3:3}, at: sock_ioctl+0x1bf/0x640 net/socket.c:1248
 #1: ffffffff8d5911a8 (rtnl_mutex){+.+.}-{3:3}, at: vlan_ioctl_handler+0xb7/0xec0 net/8021q/vlan.c:553
2 locks held by getty/3292:
 #0: ffff88802682f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244
 #1: ffffc90002d162e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xe50/0x13c0 drivers/tty/n_tty.c:2124
2 locks held by kworker/0:6/3681:
 #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline]
 #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
 #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260
 #1: ffffc90003f6fda8 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264
5 locks held by kworker/u4:10/15741:
3 locks held by kworker/1:0/13233:
 #0: ffff88814a9e5138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff88814a9e5138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff88814a9e5138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff88814a9e5138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline]
 #0: ffff88814a9e5138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
 #0: ffff88814a9e5138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260
 #1: ffffc90004b27da8 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264
 #2: ffffffff8d5911a8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xe/0x20 net/ipv6/addrconf.c:4620
3 locks held by kworker/0:0/18243:
 #0: ffff88814a9e5138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff88814a9e5138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff88814a9e5138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff88814a9e5138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline]
 #0: ffff88814a9e5138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
 #0: ffff88814a9e5138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260
 #1: ffffc90007ba7da8 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264
 #2: ffffffff8d5911a8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xe/0x20 net/ipv6/addrconf.c:4620
3 locks held by kworker/0:3/18230:
 #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline]
 #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
 #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260
 #1: ffffc90002d5fda8 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264
 #2: ffffffff8d5911a8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:263
1 lock held by syz-executor.5/23422:
 #0: ffffffff8d5911a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8d5911a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3e5/0xc90 net/core/rtnetlink.c:6086
2 locks held by kworker/u4:2/23477:

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

NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted 5.19.0-rc3-syzkaller-00573-gebeae54d3a77 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1e6/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xc22/0xf90 kernel/hung_task.c:378
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 16 Comm: pr/ttyS0 Not tainted 5.19.0-rc3-syzkaller-00573-gebeae54d3a77 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:preempt_count_add+0x3f/0x140 kernel/sched/core.c:5610
Code: 53 83 e0 07 89 fb 48 c1 e9 03 83 c0 03 0f b6 14 11 38 d0 7c 08 84 d2 0f 85 e1 00 00 00 8b 15 88 b4 a2 0f 65 01 1d 41 7a b0 7e <85> d2 75 11 65 8b 05 36 7a b0 7e 0f b6 c0 3d f4 00 00 00 7f 64 65
RSP: 0018:ffffc90000157af0 EFLAGS: 00000082
RAX: 0000000000000003 RBX: 0000000000000001 RCX: 1ffffffff21e9530
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000001
RBP: 0000068a35f21d72 R08: 0000000000000005 R09: 0000000000000000
R10: 00000000000026fe R11: 0000000000000001 R12: 0000000000000001
R13: 0000000000000899 R14: fffffbfff2243266 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c0005bc3a8 CR3: 000000000ba8e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 delay_tsc+0x38/0xb0 arch/x86/lib/delay.c:79
 wait_for_lsr+0x76/0xf0 drivers/tty/serial/8250/8250_port.c:2095
 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3356 [inline]
 serial8250_console_write+0xc87/0xfe0 drivers/tty/serial/8250/8250_port.c:3438
 call_console_driver kernel/printk/printk.c:2078 [inline]
 __console_emit_next_record+0x896/0xa60 kernel/printk/printk.c:2919
 console_emit_next_record kernel/printk/printk.c:3724 [inline]
 printk_kthread_func.cold+0x702/0x73d kernel/printk/printk.c:3843
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
 </TASK>
----------------
Code disassembly (best guess):
   0:	53                   	push   %rbx
   1:	83 e0 07             	and    $0x7,%eax
   4:	89 fb                	mov    %edi,%ebx
   6:	48 c1 e9 03          	shr    $0x3,%rcx
   a:	83 c0 03             	add    $0x3,%eax
   d:	0f b6 14 11          	movzbl (%rcx,%rdx,1),%edx
  11:	38 d0                	cmp    %dl,%al
  13:	7c 08                	jl     0x1d
  15:	84 d2                	test   %dl,%dl
  17:	0f 85 e1 00 00 00    	jne    0xfe
  1d:	8b 15 88 b4 a2 0f    	mov    0xfa2b488(%rip),%edx        # 0xfa2b4ab
  23:	65 01 1d 41 7a b0 7e 	add    %ebx,%gs:0x7eb07a41(%rip)        # 0x7eb07a6b
* 2a:	85 d2                	test   %edx,%edx <-- trapping instruction
  2c:	75 11                	jne    0x3f
  2e:	65 8b 05 36 7a b0 7e 	mov    %gs:0x7eb07a36(%rip),%eax        # 0x7eb07a6b
  35:	0f b6 c0             	movzbl %al,%eax
  38:	3d f4 00 00 00       	cmp    $0xf4,%eax
  3d:	7f 64                	jg     0xa3
  3f:	65                   	gs

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-net-kasan-gce 2022/06/26 16:57 net-next ebeae54d3a77 a371c43c .config log report info INFO: task hung in cfg80211_dfs_channels_update_work
* Struck through repros no longer work on HEAD.