[syzbot] [wireless?] INFO: task hung in cfg80211_dfs_channels_update_work (8)

From: syzbot
Date: Wed Oct 09 2024 - 12:19:10 EST


Hello,

syzbot found the following issue on:

HEAD commit: 5b7c893ed5ed Merge tag 'ntfs3_for_6.12' of https://github...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1648d7d0580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7cd9e7e4a8a0a15b
dashboard link: https://syzkaller.appspot.com/bug?extid=0e0f5ef531ead9783803
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/508d25adbdbb/disk-5b7c893e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ecd795cf996e/vmlinux-5b7c893e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d5433a3025f3/bzImage-5b7c893e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0e0f5ef531ead9783803@xxxxxxxxxxxxxxxxxxxxxxxxx

INFO: task kworker/u8:1:12 blocked for more than 156 seconds.
Not tainted 6.12.0-rc2-syzkaller-00050-g5b7c893ed5ed #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:1 state:D stack:20944 pid:12 tgid:12 ppid:2 flags:0x00004000
Workqueue: cfg80211 cfg80211_dfs_channels_update_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x1895/0x4b30 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6767
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752
cfg80211_dfs_channels_update_work+0xbf/0x610 net/wireless/mlme.c:1021
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
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>
INFO: task kworker/u8:6:2870 blocked for more than 157 seconds.
Not tainted 6.12.0-rc2-syzkaller-00050-g5b7c893ed5ed #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:6 state:D stack:21264 pid:2870 tgid:2870 ppid:2 flags:0x00004000
Workqueue: events_unbound linkwatch_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x1895/0x4b30 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6767
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752
linkwatch_event+0xe/0x60 net/core/link_watch.c:276
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
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>
INFO: task dhcpcd:4898 blocked for more than 158 seconds.
Not tainted 6.12.0-rc2-syzkaller-00050-g5b7c893ed5ed #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:dhcpcd state:D stack:19736 pid:4898 tgid:4898 ppid:4897 flags:0x00000002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x1895/0x4b30 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6767
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752
rtnl_lock net/core/rtnetlink.c:79 [inline]
rtnl_dumpit+0x99/0x200 net/core/rtnetlink.c:6505
netlink_dump+0x647/0xd80 net/netlink/af_netlink.c:2325
__netlink_dump_start+0x5a2/0x790 net/netlink/af_netlink.c:2440
netlink_dump_start include/linux/netlink.h:339 [inline]
rtnetlink_dump_start net/core/rtnetlink.c:6535 [inline]
rtnetlink_rcv_msg+0xb3d/0xcf0 net/core/rtnetlink.c:6602
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2550
netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1357
netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1901
sock_sendmsg_nosec net/socket.c:729 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:744
__sys_sendto+0x39b/0x4f0 net/socket.c:2209
__do_sys_sendto net/socket.c:2221 [inline]
__se_sys_sendto net/socket.c:2217 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2217
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: 0033:0x7fc13d7fdad7
RSP: 002b:00007ffe7cb63fc8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007ffe7cb650f0 RCX: 00007fc13d7fdad7
RDX: 0000000000000014 RSI: 00007ffe7cb65010 RDI: 0000000000000018
RBP: 00007ffe7cb65080 R08: 00007ffe7cb64ff4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000012
R13: 00007ffe7cb64ff4 R14: 00007ffe7cb65010 R15: 0000000000000105
</TASK>
INFO: task kworker/0:7:5304 blocked for more than 160 seconds.
Not tainted 6.12.0-rc2-syzkaller-00050-g5b7c893ed5ed #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:7 state:D stack:19184 pid:5304 tgid:5304 ppid:2 flags:0x00004000
Workqueue: events rfkill_global_led_trigger_worker
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x1895/0x4b30 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6767
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752
rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
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>
INFO: task syz.3.1434:13868 blocked for more than 160 seconds.
Not tainted 6.12.0-rc2-syzkaller-00050-g5b7c893ed5ed #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1434 state:D stack:22000 pid:13868 tgid:13864 ppid:12830 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x1895/0x4b30 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6767
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752
cfg80211_rfkill_set_block+0x1e/0x50 net/wireless/core.c:311
rfkill_set_block+0x1f1/0x440 net/rfkill/core.c:346
rfkill_fop_write+0x5b8/0x790 net/rfkill/core.c:1301
vfs_write+0x29c/0xc90 fs/read_write.c:681
ksys_write+0x183/0x2b0 fs/read_write.c:736
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: 0033:0x7f28e037dff9
RSP: 002b:00007f28dfd58038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f28e0536130 RCX: 00007f28e037dff9
RDX: 0000000000000008 RSI: 0000000020000080 RDI: 000000000000000b
RBP: 00007f28e03f0296 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f28e0536130 R15: 00007f28e065fa28
</TASK>

Showing all locks held in the system:
3 locks held by kworker/0:0/8:
#0: ffff88801ac81948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
#0: ffff88801ac81948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
#1: ffffc900000d7d00 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
#1: ffffc900000d7d00 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
#2: ffffffff8fcd1dc8 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x99/0xfd0 net/wireless/reg.c:2480
3 locks held by kworker/u8:1/12:
#0: ffff888145ae5148 ((wq_completion)cfg80211){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
#0: ffff888145ae5148 ((wq_completion)cfg80211){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
#1: ffffc90000117d00 ((work_completion)(&(&rdev->dfs_update_channels_wk)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
#1: ffffc90000117d00 ((work_completion)(&(&rdev->dfs_update_channels_wk)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
#2: ffffffff8fcd1dc8 (rtnl_mutex){+.+.}-{3:3}, at: cfg80211_dfs_channels_update_work+0xbf/0x610 net/wireless/mlme.c:1021
1 lock held by khungtaskd/30:
#0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720
3 locks held by kworker/u8:6/2870:
#0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
#0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
#1: ffffc90009947d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
#1: ffffc90009947d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
#2: ffffffff8fcd1dc8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276
1 lock held by syslogd/4666:
#0: ffff8880b863ea98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:593
2 locks held by dhcpcd/4898:
#0: ffff88807d8846c8 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0x119/0x790 net/netlink/af_netlink.c:2404
#1: ffffffff8fcd1dc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#1: ffffffff8fcd1dc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_dumpit+0x99/0x200 net/core/rtnetlink.c:6505
2 locks held by getty/4991:
#0: ffff88802ef9e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
3 locks held by kworker/1:4/5281:
#0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
#0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
#1: ffffc90004177d00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
#1: ffffc90004177d00 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
#2: ffffffff8fcd1dc8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
3 locks held by kworker/0:7/5304:
#0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
#0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
#1: ffffc90004287d00 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
#1: ffffc90004287d00 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
#2: ffffffff8ffa9168 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182
2 locks held by kworker/u8:8/5450:
5 locks held by kworker/u8:12/9626:
#0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
#0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
#1: ffffc90002e5fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
#1: ffffc90002e5fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
#2: ffffffff8fcc52d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580
#3: ffffffff8fcd1dc8 (rtnl_mutex){+.+.}-{3:3}, at: cleanup_net+0x6af/0xcc0 net/core/net_namespace.c:616
#4: ffffffff8e93d378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline]
#4: ffffffff8e93d378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976
3 locks held by kworker/u8:13/9628:
#0: ffff88814b3ef148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
#0: ffff88814b3ef148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
#1: ffffc9000324fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
#1: ffffc9000324fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
#2: ffffffff8fcd1dc8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4196
1 lock held by syz-executor/12440:
#0: ffffffff8e93d378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline]
#0: ffffffff8e93d378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976
1 lock held by syz-executor/13657:
#0: ffffffff8fcd1dc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8fcd1dc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643
1 lock held by syz-executor/13702:
#0: ffffffff8fcd1dc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8fcd1dc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643
7 locks held by syz-executor/13787:
#0: ffff8880323a8420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline]
#0: ffff8880323a8420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679
#1: ffff888059ab7488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325
#2: ffff888027eb9e18 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326
#3: ffffffff8f56fea8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216
#4: ffff88805865b0e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
#4: ffff88805865b0e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline]
#4: ffff88805865b0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293
#5: ffff888058659250 (&devlink->lock_key#65){+.+.}-{3:3}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1672
#6: ffffffff8fcd1dc8 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x71/0x5c0 drivers/net/netdevsim/netdev.c:773
2 locks held by syz.3.1434/13868:
#0: ffffffff8ffa9168 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0x1a6/0x790 net/rfkill/core.c:1293
#1: ffffffff8fcd1dc8 (rtnl_mutex){+.+.}-{3:3}, at: cfg80211_rfkill_set_block+0x1e/0x50 net/wireless/core.c:311
2 locks held by syz-executor/13914:
#0: ffff88806cd64118 (&data->open_mutex){+.+.}-{3:3}, at: vhci_create_device+0x34/0x6a0 drivers/bluetooth/hci_vhci.c:469
#1: ffffffff8ffa9168 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_register+0x34/0x8c0 net/rfkill/core.c:1071
2 locks held by syz-executor/13920:
#0: ffff8881c2079118 (&data->open_mutex){+.+.}-{3:3}, at: vhci_create_device+0x34/0x6a0 drivers/bluetooth/hci_vhci.c:469
#1: ffffffff8ffa9168 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_register+0x34/0x8c0 net/rfkill/core.c:1071

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc2-syzkaller-00050-g5b7c893ed5ed #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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: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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 13921 Comm: syz-executor Not tainted 6.12.0-rc2-syzkaller-00050-g5b7c893ed5ed #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:979 [inline]
RIP: 0010:debug_check_no_obj_freed+0x24e/0x580 lib/debugobjects.c:1019
Code: bc c0 a8 50 59 9a 48 89 7c 24 20 e8 dc ae 0c 07 48 89 44 24 18 4c 89 fb 48 c1 eb 03 48 b8 00 00 00 00 00 fc ff df 80 3c 03 00 <74> 08 4c 89 ff e8 58 06 3c fd 49 8b 07 48 85 c0 0f 84 eb 02 00 00
RSP: 0018:ffffc900044df720 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: 1ffffffff34ca93f RCX: 0000000000000001
RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffc900044df600
RBP: ffffc900044df868 R08: 0000000000000003 R09: fffff5200089bec0
R10: dffffc0000000000 R11: fffff5200089bec0 R12: ffff88805e5b3000
R13: ffff88805e5b2000 R14: 0000000000000000 R15: ffffffff9a6549f8
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005568deb02f20 CR3: 000000000e734000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
free_pages_prepare mm/page_alloc.c:1115 [inline]
free_unref_page+0x41b/0xf20 mm/page_alloc.c:2638
vfree+0x186/0x2e0 mm/vmalloc.c:3361
kcov_put kernel/kcov.c:439 [inline]
kcov_close+0x28/0x50 kernel/kcov.c:535
__fput+0x23f/0x880 fs/file_table.c:431
task_work_run+0x24f/0x310 kernel/task_work.c:228
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0xa2f/0x28e0 kernel/exit.c:939
do_group_exit+0x207/0x2c0 kernel/exit.c:1088
get_signal+0x16a3/0x1740 kernel/signal.c:2917
arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218
do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc04337dbfb
Code: Unable to access opcode bytes at 0x7fc04337dbd1.
RSP: 002b:00007ffdb51fe900 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffff4 RBX: 0000000000040000 RCX: 00007fc04337dbfb
RDX: 0000000000040000 RSI: ffffffff80086301 RDI: 00000000000000df
RBP: 00007fc043536600 R08: 00000000000000da R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
</TASK>


---
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