[v6.1] INFO: task hung in deactivate_super (2)

1 view
Skip to first unread message

syzbot

unread,
Feb 14, 2024, 12:27:19 AMFeb 14
to syzkaller...@googlegroups.com
Hello,

syzbot found the following issue on:

HEAD commit: f1bb70486c9c Linux 6.1.77
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=17f2b500180000
kernel config: https://syzkaller.appspot.com/x/.config?x=39447811cb133e7e
dashboard link: https://syzkaller.appspot.com/bug?extid=5e5cc76a467644c87867
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/f93cb7e9dad2/disk-f1bb7048.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/22703d1d86ee/vmlinux-f1bb7048.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4129725af309/bzImage-f1bb7048.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5e5cc7...@syzkaller.appspotmail.com

INFO: task syz-executor.0:7315 blocked for more than 150 seconds.
Not tainted 6.1.77-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0 state:D stack:26152 pid:7315 ppid:5577 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x142d/0x4550 kernel/sched/core.c:6558
schedule+0xbf/0x180 kernel/sched/core.c:6634
rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189
deactivate_super+0xa9/0xe0 fs/super.c:362
cleanup_mnt+0x490/0x520 fs/namespace.c:1186
task_work_run+0x246/0x300 kernel/task_work.c:179
exit_task_work include/linux/task_work.h:38 [inline]
do_exit+0xa73/0x26a0 kernel/exit.c:869
do_group_exit+0x202/0x2b0 kernel/exit.c:1019
get_signal+0x16f7/0x17d0 kernel/signal.c:2862
arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:168
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204
__syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:297
do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fe9468a91b5
RSP: 002b:00007fe9475dd010 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007fe9469ac050 RCX: 00007fe9468a91b5
RDX: 00007fe9475dd050 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fe9468ca47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 000000000000006e R14: 00007fe9469ac050 R15: 00007ffc6e8c6878
</TASK>

Showing all locks held in the system:
3 locks held by kworker/u4:1/11:
#0: ffff8880186ef138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#1: ffffc90000107d20 ((work_completion)(&(&rdev->dfs_update_channels_wk)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#2: ffffffff8e294ae8 (rtnl_mutex){+.+.}-{3:3}, at: cfg80211_dfs_channels_update_work+0xbb/0x610 net/wireless/mlme.c:888
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8d12a910 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8d12b110 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by khungtaskd/28:
#0: ffffffff8d12a740 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:318 [inline]
#0: ffffffff8d12a740 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:759 [inline]
#0: ffffffff8d12a740 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494
2 locks held by getty/3310:
#0: ffff88814bc5e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2188
2 locks held by kworker/u4:22/6094:
5 locks held by kworker/u4:28/6228:
#0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#1: ffffc90008f67d20 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#2: ffff88804f2e07c8 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: wiphy_lock include/net/cfg80211.h:5639 [inline]
#2: ffff88804f2e07c8 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: cfg80211_wiphy_work+0x31/0x250 net/wireless/core.c:420
#3: ffff88804f2e2af8 (&local->mtx){+.+.}-{3:3}, at: ieee80211_scan_work+0xb7/0x1d70 net/mac80211/scan.c:1071
#4: ffffffff8d12fd38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
#4: ffffffff8d12fd38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x479/0x8a0 kernel/rcu/tree_exp.h:949
1 lock held by syz-executor.0/7315:
#0: ffff888048a360e0 (&type->s_umount_key#32){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:362
4 locks held by syz-executor.0/8206:
4 locks held by kworker/u4:32/8491:
#0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#1: ffffc90004ecfd20 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#2: ffff8880459f87c8 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: wiphy_lock include/net/cfg80211.h:5639 [inline]
#2: ffff8880459f87c8 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: cfg80211_wiphy_work+0x31/0x250 net/wireless/core.c:420
#3: ffff8880459faaf8 (&local->mtx){+.+.}-{3:3}, at: ieee80211_scan_work+0xb7/0x1d70 net/mac80211/scan.c:1071
4 locks held by kworker/0:23/8609:
#0: ffff888012470d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#1: ffffc90005f1fd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#2: ffffffff8e294ae8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263
#3: ffffffff8d12fd38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#3: ffffffff8d12fd38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3b0/0x8a0 kernel/rcu/tree_exp.h:949
2 locks held by kworker/0:24/8611:
#0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#1: ffffc90005f4fd20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
1 lock held by syz-executor.0/9003:
#0: ffff888048a360e0 (&type->s_umount_key#32){++++}-{3:3}, at: user_get_super+0x11a/0x250 fs/super.c:878
1 lock held by syz-executor.0/9195:
#0: ffffffff8e294ae8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e294ae8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6119
1 lock held by dhcpcd/9257:
#0: ffff88803bfa0130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1745 [inline]
#0: ffff88803bfa0130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xd00 net/packet/af_packet.c:3198
2 locks held by syz-executor.1/9259:
#0: ffffffff8e2f5970 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:860
#1: ffffffff8e294ae8 (rtnl_mutex){+.+.}-{3:3}, at: nl80211_pre_doit+0x5b/0x8a0 net/wireless/nl80211.c:16186
2 locks held by syz-executor.1/9262:
#0: ffffffff8e2f5970 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:860
#1: ffffffff8e294ae8 (rtnl_mutex){+.+.}-{3:3}, at: nl80211_pre_doit+0x5b/0x8a0 net/wireless/nl80211.c:16186
2 locks held by syz-executor.4/9261:
#0: ffffffff8e2f5970 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:860
#1: ffffffff8e294ae8 (rtnl_mutex){+.+.}-{3:3}, at: nl80211_pre_doit+0x5b/0x8a0 net/wireless/nl80211.c:16186
2 locks held by syz-executor.4/9263:
#0: ffffffff8e2f5970 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:860
#1: ffffffff8e294ae8 (rtnl_mutex){+.+.}-{3:3}, at: nl80211_pre_doit+0x5b/0x8a0 net/wireless/nl80211.c:16186

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

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.77-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xf88/0xfd0 kernel/hung_task.c:377
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8206 Comm: syz-executor.0 Not tainted 6.1.77-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
RIP: 0010:_compound_head include/linux/page-flags.h:255 [inline]
RIP: 0010:PageUptodate+0x39/0x290 include/linux/page-flags.h:736
Code: 00 00 fc ff df e8 07 3e 89 ff 49 8d 5e 08 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 2d ab e0 ff 48 8b 1b 48 89 de <48> 83 e6 01 31 ff e8 bc 41 89 ff 48 89 d8 48 83 e0 01 0f 85 96 00
RSP: 0018:ffffc9000303f668 EFLAGS: 00000246
RAX: 1ffffd40001a0279 RBX: ffffea0001888e48 RCX: 0000000000040000
RDX: ffffc9001978b000 RSI: ffffea0001888e48 RDI: 0000000000040000
RBP: 0000000000000800 R08: ffffffff8201efb1 R09: fffff940001a0279
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffea0000d013c0
R13: 0000000000000042 R14: ffffea0000d013c0 R15: dffffc0000000000
FS: 00007fe9475fe6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200bd038 CR3: 0000000043462000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
init_page_buffers+0xc4/0x340 fs/buffer.c:896
grow_dev_page fs/buffer.c:953 [inline]
grow_buffers fs/buffer.c:1011 [inline]
__getblk_slow fs/buffer.c:1038 [inline]
__getblk_gfp+0x55e/0xa20 fs/buffer.c:1333
sb_getblk include/linux/buffer_head.h:356 [inline]
ext4_getblk+0x2a7/0x7c0 fs/ext4/inode.c:876
ext4_bread+0x2a/0x170 fs/ext4/inode.c:922
ext4_quota_write+0x21e/0x570 fs/ext4/super.c:7135
qtree_write_dquot+0x23f/0x530 fs/quota/quota_tree.c:431
v2_write_dquot+0x11c/0x190 fs/quota/quota_v2.c:358
dquot_commit+0x3c0/0x510 fs/quota/dquot.c:512
ext4_write_dquot+0x1e8/0x2b0 fs/ext4/super.c:6753
mark_dquot_dirty fs/quota/dquot.c:372 [inline]
do_set_dqblk fs/quota/dquot.c:2845 [inline]
dquot_set_dqblk+0xce7/0xf20 fs/quota/dquot.c:2861
quota_setquota+0x6d3/0x840 fs/quota/quota.c:310
__do_sys_quotactl fs/quota/quota.c:960 [inline]
__se_sys_quotactl+0x2b1/0x770 fs/quota/quota.c:916
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fe94687dda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe9475fe0c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fe9469abf80 RCX: 00007fe94687dda9
RDX: 0000000000000000 RSI: 0000000020000000 RDI: ffffffff80000800
RBP: 00007fe9468ca47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000240 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fe9469abf80 R15: 00007ffc6e8c6878
</TASK>


---
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