[syzbot] [bluetooth?] BUG: workqueue leaked atomic, lock or RCU: kworker/u33:NUM[NUM]
From: syzbot
Date: Fri Jul 26 2024 - 08:17:34 EST
Hello,
syzbot found the following issue on:
HEAD commit: 22f902dfc51e Merge tag 'i2c-for-6.10-rc7' of git://git.ker..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=156bc135980000
kernel config: https://syzkaller.appspot.com/x/.config?x=de2d4dc103148cd6
dashboard link: https://syzkaller.appspot.com/bug?extid=45ac74737e866894acb0
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17243d76980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15832bc1980000
Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-22f902df.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/52eba6820000/vmlinux-22f902df.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b9c5671dd5ff/bzImage-22f902df.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+45ac74737e866894acb0@xxxxxxxxxxxxxxxxxxxxxxxxx
BUG: workqueue leaked atomic, lock or RCU: kworker/u33:2[5195]
preempt=0x00000000 lock=0->1 RCU=0->0 workfn=hci_rx_work
1 lock held by kworker/u33:2/5195:
#0: ffff88801ac26518 (&chan->lock/1){+.+.}-{3:3}, at: l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
#0: ffff88801ac26518 (&chan->lock/1){+.+.}-{3:3}, at: l2cap_conless_channel net/bluetooth/l2cap_core.c:6764 [inline]
#0: ffff88801ac26518 (&chan->lock/1){+.+.}-{3:3}, at: l2cap_recv_frame+0x14f2/0x8ea0 net/bluetooth/l2cap_core.c:6830
CPU: 3 PID: 5195 Comm: kworker/u33:2 Not tainted 6.10.0-rc6-syzkaller-00215-g22f902dfc51e #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: hci0 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:114
process_one_work+0x11ea/0x1b40 kernel/workqueue.c:3269
process_scheduled_works kernel/workqueue.c:3329 [inline]
worker_thread+0x6c8/0xf30 kernel/workqueue.c:3409
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
======================================================
WARNING: possible circular locking dependency detected
6.10.0-rc6-syzkaller-00215-g22f902dfc51e #0 Not tainted
------------------------------------------------------
kworker/u33:2/5195 is trying to acquire lock:
ffff88801ef0a948 ((wq_completion)hci0#2){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3223
but task is already holding lock:
ffff88801ac26518 (&chan->lock/1){+.+.}-{3:3}, at: l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
ffff88801ac26518 (&chan->lock/1){+.+.}-{3:3}, at: l2cap_conless_channel net/bluetooth/l2cap_core.c:6764 [inline]
ffff88801ac26518 (&chan->lock/1){+.+.}-{3:3}, at: l2cap_recv_frame+0x14f2/0x8ea0 net/bluetooth/l2cap_core.c:6830
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&chan->lock/1){+.+.}-{3:3}:
__lock_release kernel/locking/lockdep.c:5468 [inline]
lock_release+0x33e/0x6c0 kernel/locking/lockdep.c:5774
process_one_work+0xa96/0x1b40 kernel/workqueue.c:3255
process_scheduled_works kernel/workqueue.c:3329 [inline]
worker_thread+0x6c8/0xf30 kernel/workqueue.c:3409
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
-> #0 ((wq_completion)hci0#2){+.+.}-{0:0}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
lock_acquire kernel/locking/lockdep.c:5754 [inline]
lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
process_one_work+0x12a6/0x1b40 kernel/workqueue.c:3223
process_scheduled_works kernel/workqueue.c:3329 [inline]
worker_thread+0x6c8/0xf30 kernel/workqueue.c:3409
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&chan->lock/1);
lock((wq_completion)hci0#2);
lock(&chan->lock/1);
lock((wq_completion)hci0#2);
*** DEADLOCK ***
1 lock held by kworker/u33:2/5195:
#0: ffff88801ac26518 (&chan->lock/1){+.+.}-{3:3}, at: l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
#0: ffff88801ac26518 (&chan->lock/1){+.+.}-{3:3}, at: l2cap_conless_channel net/bluetooth/l2cap_core.c:6764 [inline]
#0: ffff88801ac26518 (&chan->lock/1){+.+.}-{3:3}, at: l2cap_recv_frame+0x14f2/0x8ea0 net/bluetooth/l2cap_core.c:6830
stack backtrace:
CPU: 2 PID: 5195 Comm: kworker/u33:2 Not tainted 6.10.0-rc6-syzkaller-00215-g22f902dfc51e #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: hci0 hci_cmd_timeout
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
lock_acquire kernel/locking/lockdep.c:5754 [inline]
lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
process_one_work+0x12a6/0x1b40 kernel/workqueue.c:3223
process_scheduled_works kernel/workqueue.c:3329 [inline]
worker_thread+0x6c8/0xf30 kernel/workqueue.c:3409
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Bluetooth: hci0: command tx timeout
BUG: workqueue leaked atomic, lock or RCU: kworker/u33:2[5195]
preempt=0x00000000 lock=1->0 RCU=0->0 workfn=hci_cmd_timeout
INFO: lockdep is turned off.
CPU: 2 PID: 5195 Comm: kworker/u33:2 Not tainted 6.10.0-rc6-syzkaller-00215-g22f902dfc51e #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: hci0 hci_cmd_timeout
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:114
process_one_work+0x11ea/0x1b40 kernel/workqueue.c:3269
process_scheduled_works kernel/workqueue.c:3329 [inline]
worker_thread+0x6c8/0xf30 kernel/workqueue.c:3409
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Bluetooth: hci0: command tx timeout
Bluetooth: hci0: command tx timeout
Bluetooth: hci0: command tx timeout
---
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