[v6.1] INFO: task hung in deactivate_super (3)

0 views
Skip to first unread message

syzbot

unread,
May 27, 2024, 8:00:27 AMMay 27
to syzkaller...@googlegroups.com
Hello,

syzbot found the following issue on:

HEAD commit: 88690811da69 Linux 6.1.92
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10bf41e8980000
kernel config: https://syzkaller.appspot.com/x/.config?x=f084fbeeff2de042
dashboard link: https://syzkaller.appspot.com/bug?extid=4ae63a93dbe1440d6ba3
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9040ec940045/disk-88690811.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/dc70128611fd/vmlinux-88690811.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f05abc0b618b/Image-88690811.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4ae63a...@syzkaller.appspotmail.com

INFO: task syz-executor.0:7666 blocked for more than 143 seconds.
Not tainted 6.1.92-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0 state:D stack:0 pid:7666 ppid:1 flags:0x0000000d
Call trace:
__switch_to+0x320/0x754 arch/arm64/kernel/process.c:553
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0xee4/0x1c98 kernel/sched/core.c:6558
schedule+0xc4/0x170 kernel/sched/core.c:6634
rwsem_down_write_slowpath+0xc80/0x156c kernel/locking/rwsem.c:1189
__down_write_common kernel/locking/rwsem.c:1314 [inline]
__down_write kernel/locking/rwsem.c:1323 [inline]
down_write+0x84/0x88 kernel/locking/rwsem.c:1574
deactivate_super+0xe8/0x110 fs/super.c:362
cleanup_mnt+0x394/0x41c fs/namespace.c:1186
__cleanup_mnt+0x20/0x30 fs/namespace.c:1193
task_work_run+0x240/0x2f0 kernel/task_work.c:179
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
do_notify_resume+0x2148/0x3474 arch/arm64/kernel/signal.c:1132
prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline]
exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline]
el0_svc+0x9c/0x168 arch/arm64/kernel/entry-common.c:638
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
INFO: task syz-executor.4:8761 blocked for more than 143 seconds.
Not tainted 6.1.92-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4 state:D stack:0 pid:8761 ppid:7433 flags:0x0000000d
Call trace:
__switch_to+0x320/0x754 arch/arm64/kernel/process.c:553
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0xee4/0x1c98 kernel/sched/core.c:6558
schedule+0xc4/0x170 kernel/sched/core.c:6634
jfs_flush_journal+0x5d8/0xd64 fs/jfs/jfs_logmgr.c:1564
jfs_sync_fs+0x80/0xac fs/jfs/super.c:684
dquot_quota_sync+0xc4/0x434 fs/quota/dquot.c:755
quota_sync_one+0x114/0x188 fs/quota/quota.c:60
iterate_supers+0x124/0x1dc fs/super.c:746
quota_sync_all fs/quota/quota.c:69 [inline]
__do_sys_quotactl fs/quota/quota.c:937 [inline]
__se_sys_quotactl fs/quota/quota.c:916 [inline]
__arm64_sys_quotactl+0x39c/0x7a0 fs/quota/quota.c:916
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffff800015a24e70 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:516
1 lock held by rcu_tasks_trace/13:
#0: ffff800015a25670 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:516
2 locks held by kworker/1:1/24:
#0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x664/0x1404 kernel/workqueue.c:2265
#1: ffff800019f37c20 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x6a8/0x1404 kernel/workqueue.c:2267
1 lock held by khungtaskd/28:
#0: ffff800015a24ca0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:349
2 locks held by getty/3986:
#0: ffff0000d629f098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
#1: ffff80001bcf02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1214 drivers/tty/n_tty.c:2188
1 lock held by syz-fuzzer/4221:
3 locks held by syz-executor.2/4765:
#0: ffff0000d9b5d0b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:552 [inline]
#0: ffff0000d9b5d0b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x1d8/0x4a4 net/bluetooth/hci_core.c:2736
#1: ffff0000d9b5c078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x39c/0xf6c net/bluetooth/hci_sync.c:5005
#2: ffff800017f7ee88 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1805 [inline]
#2: ffff800017f7ee88 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xb0/0x27c net/bluetooth/hci_conn.c:2441
3 locks held by syz-executor.1/7425:
#0: ffff0000f29c50b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:552 [inline]
#0: ffff0000f29c50b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x1d8/0x4a4 net/bluetooth/hci_core.c:2736
#1: ffff0000f29c4078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x39c/0xf6c net/bluetooth/hci_sync.c:5005
#2: ffff800017f7ee88 (hci_cb_list_lock){+.+.}


---
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.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup
Reply all
Reply to author
Forward
0 new messages