INFO: task hung in netdev_run_todo (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 7575fdda Merge tag 'platform-drivers-x86-v5.9-2' of git://..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1110b33f900000
kernel config: https://syzkaller.appspot.com/x/.config?x=c06bcf3cc963d91c
dashboard link: https://syzkaller.appspot.com/bug?extid=9d77543f47951a63d5c1
compiler: gcc (GCC) 10.1.0-syz 20200507

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9d7754...@syzkaller.appspotmail.com

INFO: task kworker/u4:2:26 blocked for more than 143 seconds.
Not tainted 5.9.0-rc8-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:2 state:D stack:24024 pid: 26 ppid: 2 flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
context_switch kernel/sched/core.c:3778 [inline]
__schedule+0xec9/0x2280 kernel/sched/core.c:4527
schedule+0xd0/0x2a0 kernel/sched/core.c:4602
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661
__mutex_lock_common kernel/locking/mutex.c:1033 [inline]
__mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103
netdev_run_todo+0x8f8/0xdb0 net/core/dev.c:10183
ip6gre_exit_batch_net+0x516/0x750 net/ipv6/ip6_gre.c:1610
ops_exit_list+0x10d/0x160 net/core/net_namespace.c:189
cleanup_net+0x4ea/0xa00 net/core/net_namespace.c:603
process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
kthread+0x3b5/0x4a0 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
INFO: task kworker/0:4:8175 blocked for more than 143 seconds.
Not tainted 5.9.0-rc8-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:4 state:D stack:25936 pid: 8175 ppid: 2 flags:0x00004000
Workqueue: events linkwatch_event
Call Trace:
context_switch kernel/sched/core.c:3778 [inline]
__schedule+0xec9/0x2280 kernel/sched/core.c:4527
schedule+0xd0/0x2a0 kernel/sched/core.c:4602
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661
__mutex_lock_common kernel/locking/mutex.c:1033 [inline]
__mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103
linkwatch_event+0xb/0x60 net/core/link_watch.c:250
process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
kthread+0x3b5/0x4a0 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
INFO: task syz-executor.5:8896 blocked for more than 144 seconds.
Not tainted 5.9.0-rc8-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5 state:D stack:27440 pid: 8896 ppid: 6920 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:3778 [inline]
__schedule+0xec9/0x2280 kernel/sched/core.c:4527
schedule+0xd0/0x2a0 kernel/sched/core.c:4602
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661
__mutex_lock_common kernel/locking/mutex.c:1033 [inline]
__mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103
tc_new_tfilter+0x928/0x2130 net/sched/cls_api.c:2020
rtnetlink_rcv_msg+0x80f/0xad0 net/core/rtnetlink.c:5554
netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2470
netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330
netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919
sock_sendmsg_nosec net/socket.c:651 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:671
____sys_sendmsg+0x331/0x810 net/socket.c:2353
___sys_sendmsg+0xf3/0x170 net/socket.c:2407
__sys_sendmmsg+0x195/0x480 net/socket.c:2497
__do_sys_sendmmsg net/socket.c:2526 [inline]
__se_sys_sendmmsg net/socket.c:2523 [inline]
__x64_sys_sendmmsg+0x99/0x100 net/socket.c:2523
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45de29
Code: Bad RIP value.
RSP: 002b:00007f9e84d3cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 0000000000027f40 RCX: 000000000045de29
RDX: 04924924924926d3 RSI: 0000000020000200 RDI: 0000000000000005
RBP: 000000000118c160 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118c124
R13: 00007ffdec73781f R14: 00007f9e84d3d9c0 R15: 000000000118c124
INFO: task syz-executor.3:8909 blocked for more than 145 seconds.
Not tainted 5.9.0-rc8-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3 state:D stack:26800 pid: 8909 ppid: 6916 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:3778 [inline]
__schedule+0xec9/0x2280 kernel/sched/core.c:4527
schedule+0xd0/0x2a0 kernel/sched/core.c:4602
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661
__mutex_lock_common kernel/locking/mutex.c:1033 [inline]
__mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103
rtnl_lock net/core/rtnetlink.c:72 [inline]
rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560
netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2470
netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330
netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919
sock_sendmsg_nosec net/socket.c:651 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:671
____sys_sendmsg+0x6e8/0x810 net/socket.c:2353
___sys_sendmsg+0xf3/0x170 net/socket.c:2407
__sys_sendmsg+0xe5/0x1b0 net/socket.c:2440
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45de29
Code: Bad RIP value.
RSP: 002b:00007f269716ec78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000002e5c0 RCX: 000000000045de29
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000005
RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007ffce0487dbf R14: 00007f269716f9c0 R15: 000000000118bf2c
INFO: task syz-executor.2:8929 blocked for more than 145 seconds.
Not tainted 5.9.0-rc8-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2 state:D stack:28360 pid: 8929 ppid: 1 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:3778 [inline]
__schedule+0xec9/0x2280 kernel/sched/core.c:4527
schedule+0xd0/0x2a0 kernel/sched/core.c:4602
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661
__mutex_lock_common kernel/locking/mutex.c:1033 [inline]
__mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103
rtnl_lock net/core/rtnetlink.c:72 [inline]
rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560
netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2470
netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330
netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919
sock_sendmsg_nosec net/socket.c:651 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:671
__sys_sendto+0x21c/0x320 net/socket.c:1992
__do_sys_sendto net/socket.c:2004 [inline]
__se_sys_sendto net/socket.c:2000 [inline]
__x64_sys_sendto+0xdd/0x1b0 net/socket.c:2000
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x4178a7
Code: Bad RIP value.
RSP: 002b:00007ffdfb298fd0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00000000016a4300 RCX: 00000000004178a7
RDX: 0000000000000028 RSI: 00000000016a4350 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffdfb298fe0 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 00000000016a4350 R15: 0000000000000003

Showing all locks held in the system:
4 locks held by kworker/u4:2/26:
#0: ffff88821b047138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff88821b047138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
#0: ffff88821b047138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
#0: ffff88821b047138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
#0: ffff88821b047138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
#0: ffff88821b047138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240
#1: ffffc90000e27da8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244
#2: ffffffff8b13d830 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa00 net/core/net_namespace.c:565
#3: ffffffff8b14f0c8 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0x8f8/0xdb0 net/core/dev.c:10183
1 lock held by khungtaskd/1175:
#0: ffffffff8a067f40 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5852
1 lock held by in:imklog/6574:
#0: ffff888091a216b0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930
3 locks held by kworker/0:4/8175:
#0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
#0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
#0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
#0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
#0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240
#1: ffffc90015e77da8 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244
#2: ffffffff8b14f0c8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:250
3 locks held by kworker/0:5/8220:
#0: ffff888214886d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff888214886d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
#0: ffff888214886d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
#0: ffff888214886d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
#0: ffff888214886d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
#0: ffff888214886d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240
#1: ffffc90015fc7da8 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244
#2: ffffffff8b14f0c8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4568
2 locks held by syz-executor.5/8871:
1 lock held by syz-executor.5/8896:
#0: ffffffff8b14f0c8 (rtnl_mutex){+.+.}-{3:3}, at: tc_new_tfilter+0x928/0x2130 net/sched/cls_api.c:2020
1 lock held by syz-executor.3/8909:
#0: ffffffff8b14f0c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8b14f0c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560
1 lock held by syz-executor.2/8929:
#0: ffffffff8b14f0c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8b14f0c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560

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

NMI backtrace for cpu 0
CPU: 0 PID: 1175 Comm: khungtaskd Not tainted 5.9.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x198/0x1fd lib/dump_stack.c:118
nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline]
watchdog+0xd7d/0x1000 kernel/hung_task.c:295
kthread+0x3b5/0x4a0 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7 Comm: kworker/u4:0 Not tainted 5.9.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
RIP: 0010:lockdep_recursion_finish kernel/locking/lockdep.c:398 [inline]
RIP: 0010:lock_release+0x43a/0x8f0 kernel/locking/lockdep.c:5051
Code: 9a 02 00 00 65 4c 8b 24 25 c0 fe 01 00 49 8d bc 24 e4 08 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 <48> 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 fe 02 00 00 41
RSP: 0018:ffffc90000cdfb38 EFLAGS: 00000803
RAX: dffffc0000000000 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff8880472c8e98 RDI: ffff8880a960eaa4
RBP: 1ffff9200019bf69 R08: 0000000000000001 R09: ffff8880a960eaa0
R10: fffffbfff16b3019 R11: 0000000000000000 R12: ffff8880a960e1c0
R13: 0000000000000002 R14: ffffffff880a9b45 R15: ffff8880a960e1c0
FS: 0000000000000000(0000) GS:ffff8880ae500000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f33c36ef000 CR3: 00000000a7f77000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:174 [inline]
_raw_spin_unlock_bh+0x12/0x30 kernel/locking/spinlock.c:207
spin_unlock_bh include/linux/spinlock.h:399 [inline]
batadv_nc_purge_paths+0x2a5/0x3a0 net/batman-adv/network-coding.c:470
batadv_nc_worker+0x831/0xe50 net/batman-adv/network-coding.c:719
process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
kthread+0x3b5/0x4a0 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: ed4643521e6a Merge tag 'arm-dt-5.18' of git://git.kernel.o..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=105db1dd700000
kernel config: https://syzkaller.appspot.com/x/.config?x=77631dc57d015556
dashboard link: https://syzkaller.appspot.com/bug?extid=9d77543f47951a63d5c1
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14a8af6d700000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17dacda3700000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9d7754...@syzkaller.appspotmail.com

INFO: task kworker/1:2:3649 blocked for more than 143 seconds.
Tainted: G W 5.17.0-syzkaller-04443-ged4643521e6a #0

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

task:kworker/1:2 state:D stack:24952 pid: 3649 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5073 [inline]
__schedule+0xa9a/0x4940 kernel/sched/core.c:6382
schedule+0xd2/0x1f0 kernel/sched/core.c:6454
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6513
__mutex_lock_common kernel/locking/mutex.c:673 [inline]
__mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:733
netdev_run_todo+0x70f/0xaa0 net/core/dev.c:9967
r871xu_dev_remove+0x24f/0x2c0 drivers/staging/rtl8712/usb_intf.c:599
usb_unbind_interface+0x1d8/0x8e0 drivers/usb/core/driver.c:458
__device_release_driver+0x627/0x760 drivers/base/dd.c:1209
device_release_driver_internal drivers/base/dd.c:1242 [inline]
device_release_driver+0x26/0x40 drivers/base/dd.c:1265
bus_remove_device+0x2eb/0x5a0 drivers/base/bus.c:529
device_del+0x4f3/0xc80 drivers/base/core.c:3592
usb_disable_device+0x35b/0x7b0 drivers/usb/core/message.c:1419
usb_disconnect.cold+0x278/0x6ec drivers/usb/core/hub.c:2228
hub_port_connect drivers/usb/core/hub.c:5202 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5502 [inline]
port_event drivers/usb/core/hub.c:5660 [inline]
hub_event+0x1e74/0x4680 drivers/usb/core/hub.c:5742
process_one_work+0x996/0x1610 kernel/workqueue.c:2289
process_scheduled_works kernel/workqueue.c:2352 [inline]
worker_thread+0x854/0x1080 kernel/workqueue.c:2438
kthread+0x2e9/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
INFO: lockdep is turned off.

NMI backtrace for cpu 1

CPU: 1 PID: 27 Comm: khungtaskd Tainted: G W 5.17.0-syzkaller-04443-ged4643521e6a #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:212 [inline]
watchdog+0xc1d/0xf50 kernel/hung_task.c:369
kthread+0x2e9/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
Sending NMI from CPU 1 to CPUs 0:

NMI backtrace for cpu 0

CPU: 0 PID: 3639 Comm: syz-executor169 Tainted: G W 5.17.0-syzkaller-04443-ged4643521e6a #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

RIP: 0010:____rb_erase_color lib/rbtree.c:259 [inline]
RIP: 0010:rb_erase+0x516/0x1210 lib/rbtree.c:445
Code: 48 89 f9 48 c1 e9 03 80 3c 19 00 0f 85 bb 0b 00 00 49 8d 7d 10 4c 89 60 08 48 89 f8 48 c1 e8 03 80 3c 18 00 0f 85 90 0b 00 00 <4d> 89 ec 4d 8b 6d 10 e9 cb fd ff ff 48 b8 00 00 00 00 00 fc ff df
RSP: 0018:ffffc90002befa38 EFLAGS: 00000046
RAX: 1ffff1100fd8aaf4 RBX: dffffc0000000000 RCX: 1ffff110173873d1
RDX: ffffed10173873d0 RSI: ffff8880b9c39e80 RDI: ffff88807ec557a0
RBP: ffff88801da05790 R08: ffff8880b9c39e40 R09: 0000000000000000
R10: 0000000000000006 R11: ffff8880b9c3a958 R12: ffff88801d7d5790
R13: ffff88807ec55790 R14: ffff88801da05791 R15: ffff8880b9c39e80
FS: 00005555558cf300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f945ed6a01d CR3: 00000000222c0000 CR4: 00000000003506f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:

<TASK>
rb_erase_cached include/linux/rbtree.h:126 [inline]
__dequeue_entity kernel/sched/fair.c:624 [inline]
set_next_entity+0x334/0x5e0 kernel/sched/fair.c:4522
pick_next_task_fair+0x6ad/0xe20 kernel/sched/fair.c:7348
__pick_next_task kernel/sched/core.c:5695 [inline]
pick_next_task kernel/sched/core.c:5768 [inline]
__schedule+0x3e8/0x4940 kernel/sched/core.c:6346
schedule+0xd2/0x1f0 kernel/sched/core.c:6454
freezable_schedule include/linux/freezer.h:172 [inline]
do_nanosleep+0x24e/0x690 kernel/time/hrtimer.c:2044
hrtimer_nanosleep+0x1f9/0x4a0 kernel/time/hrtimer.c:2097
common_nsleep+0xa2/0xc0 kernel/time/posix-timers.c:1227
__do_sys_clock_nanosleep kernel/time/posix-timers.c:1267 [inline]
__se_sys_clock_nanosleep kernel/time/posix-timers.c:1245 [inline]
__x64_sys_clock_nanosleep+0x2f4/0x430 kernel/time/posix-timers.c:1245
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+0x44/0xae
RIP: 0033:0x7f945ed4a2aa
Code: 83 ff 03 74 3b 48 83 ec 28 b8 fa ff ff ff 83 ff 02 49 89 ca 0f 44 f8 64 8b 04 25 18 00 00 00 85 c0 75 2d b8 e6 00 00 00 0f 05 <89> c2 f7 da 3d 00 f0 ff ff b8 00 00 00 00 0f 47 c2 48 83 c4 28 c3
RSP: 002b:00007ffcdea2c300 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 00000000000f4240 RCX: 00007f945ed4a2aa
RDX: 00007ffcdea2c340 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 000000000000126b R08: 00000000000002cc R09: 00007ffcdea53080
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000adfd3
R13: 00007ffcdea2c37c R14: 00007ffcdea2c390 R15: 00007ffcdea2c380
</TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.178 msecs
----------------
Code disassembly (best guess):
0: 48 89 f9 mov %rdi,%rcx
3: 48 c1 e9 03 shr $0x3,%rcx
7: 80 3c 19 00 cmpb $0x0,(%rcx,%rbx,1)
b: 0f 85 bb 0b 00 00 jne 0xbcc
11: 49 8d 7d 10 lea 0x10(%r13),%rdi
15: 4c 89 60 08 mov %r12,0x8(%rax)
19: 48 89 f8 mov %rdi,%rax
1c: 48 c1 e8 03 shr $0x3,%rax
20: 80 3c 18 00 cmpb $0x0,(%rax,%rbx,1)
24: 0f 85 90 0b 00 00 jne 0xbba
* 2a: 4d 89 ec mov %r13,%r12 <-- trapping instruction
2d: 4d 8b 6d 10 mov 0x10(%r13),%r13
31: e9 cb fd ff ff jmpq 0xfffffe01
36: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
3d: fc ff df

[syzbot]

Auto-closing this bug as obsolete.
No recent activity, existing reproducers are no longer triggering the issue.