======================================================
WARNING: possible circular locking dependency detected
5.18.0-syzkaller-03023-g7e062cda7d90 #0 Not tainted
------------------------------------------------------
kworker/u4:5/1066 is trying to acquire lock:
ffff8881483b80d0 (&q->queue_lock){..-.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:374 [inline]
ffff8881483b80d0 (&q->queue_lock){..-.}-{2:2}, at: throtl_pending_timer_fn+0xf7/0x1690 block/blk-throttle.c:1152
but task is already holding lock:
ffffc900001f0d70 ((&sq->pending_timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:35 [inline]
ffffc900001f0d70 ((&sq->pending_timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x6b0 kernel/time/timer.c:1464
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 ((&sq->pending_timer)){+.-.}-{0:0}:
del_timer_sync+0x5b/0x1b0 kernel/time/timer.c:1417
throtl_pd_free+0x15/0x40 block/blk-throttle.c:500
blkcg_deactivate_policy block/blk-cgroup.c:1519 [inline]
blkcg_deactivate_policy+0x2d2/0x4e0 block/blk-cgroup.c:1497
blk_throtl_exit+0x8a/0x1a0 block/blk-throttle.c:2336
blkcg_init_queue+0x19b/0x610 block/blk-cgroup.c:1301
__alloc_disk_node+0x260/0x610 block/genhd.c:1381
__blk_mq_alloc_disk+0x133/0x1c0 block/blk-mq.c:3941
nbd_dev_add+0x3b2/0xc90 drivers/block/nbd.c:1764
nbd_genl_connect+0x11f3/0x1930 drivers/block/nbd.c:1946
genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:731
genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:792
netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2501
genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345
netlink_sendmsg+0x917/0xe10 net/netlink/af_netlink.c:1921
sock_sendmsg_nosec net/socket.c:714 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:734
____sys_sendmsg+0x6eb/0x810 net/socket.c:2492
___sys_sendmsg+0xf3/0x170 net/socket.c:2546
__sys_sendmsg net/socket.c:2575 [inline]
__do_sys_sendmsg net/socket.c:2584 [inline]
__se_sys_sendmsg net/socket.c:2582 [inline]
__x64_sys_sendmsg+0x132/0x220 net/socket.c:2582
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+0x46/0xb0
-> #1 (&blkcg->lock){....}-{2:2}:
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:349 [inline]
blkg_create+0x45e/0x1000 block/blk-cgroup.c:344
blkcg_init_queue+0xb2/0x610 block/blk-cgroup.c:1282
__alloc_disk_node+0x260/0x610 block/genhd.c:1381
__blk_alloc_disk+0x35/0x70 block/genhd.c:1421
brd_alloc.part.0+0x27f/0x7a0 drivers/block/brd.c:391
brd_alloc drivers/block/brd.c:374 [inline]
brd_init+0x1b8/0x24b drivers/block/brd.c:477
do_one_initcall+0x103/0x650 init/main.c:1295
do_initcall_level init/main.c:1368 [inline]
do_initcalls init/main.c:1384 [inline]
do_basic_setup init/main.c:1403 [inline]
kernel_init_freeable+0x6b1/0x73a init/main.c:1610
kernel_init+0x1a/0x1d0 init/main.c:1499
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
-> #0 (&q->queue_lock){..-.}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3064 [inline]
check_prevs_add kernel/locking/lockdep.c:3183 [inline]
validate_chain kernel/locking/lockdep.c:3798 [inline]
__lock_acquire+0x2ac6/0x56c0 kernel/locking/lockdep.c:5022
lock_acquire kernel/locking/lockdep.c:5634 [inline]
lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5599
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
_raw_spin_lock_irq+0x32/0x50 kernel/locking/spinlock.c:170
spin_lock_irq include/linux/spinlock.h:374 [inline]
throtl_pending_timer_fn+0xf7/0x1690 block/blk-throttle.c:1152
call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1474
expire_timers kernel/time/timer.c:1519 [inline]
__run_timers.part.0+0x679/0xa80 kernel/time/timer.c:1790
__run_timers kernel/time/timer.c:1768 [inline]
run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1803
__do_softirq+0x29b/0x9c2 kernel/softirq.c:571
invoke_softirq kernel/softirq.c:445 [inline]
__irq_exit_rcu+0x123/0x180 kernel/softirq.c:650
irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1106
asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:649
lock_acquire+0x1ef/0x570 kernel/locking/lockdep.c:5602
rcu_lock_acquire include/linux/rcupdate.h:269 [inline]
rcu_read_lock include/linux/rcupdate.h:695 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
batadv_nc_worker+0x12d/0xfa0 net/batman-adv/network-coding.c:719
process_one_work+0x996/0x1610 kernel/workqueue.c:2289
worker_thread+0x665/0x1080 kernel/workqueue.c:2436
kthread+0x2e9/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
other info that might help us debug this:
Chain exists of:
&q->queue_lock --> &blkcg->lock --> (&sq->pending_timer)
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock((&sq->pending_timer));
lock(&blkcg->lock);
lock((&sq->pending_timer));
lock(&q->queue_lock);
*** DEADLOCK ***
4 locks held by kworker/u4:5/1066:
#0: ffff88814b88c138 ((wq_completion)bat_events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff88814b88c138 ((wq_completion)bat_events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
#0: ffff88814b88c138 ((wq_completion)bat_events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
#0: ffff88814b88c138 ((wq_completion)bat_events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline]
#0: ffff88814b88c138 ((wq_completion)bat_events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
#0: ffff88814b88c138 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260
#1: ffffc90004df7da8 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264
#2: ffffffff8bd855e0 (rcu_read_lock){....}-{1:2}, at: batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:406 [inline]
#2: ffffffff8bd855e0 (rcu_read_lock){....}-{1:2}, at: batadv_nc_worker+0xf3/0xfa0 net/batman-adv/network-coding.c:719
#3: ffffc900001f0d70 ((&sq->pending_timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:35 [inline]
#3: ffffc900001f0d70 ((&sq->pending_timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x6b0 kernel/time/timer.c:1464
stack backtrace:
CPU: 1 PID: 1066 Comm: kworker/u4:5 Not tainted 5.18.0-syzkaller-03023-g7e062cda7d90 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2144
check_prev_add kernel/locking/lockdep.c:3064 [inline]
check_prevs_add kernel/locking/lockdep.c:3183 [inline]
validate_chain kernel/locking/lockdep.c:3798 [inline]
__lock_acquire+0x2ac6/0x56c0 kernel/locking/lockdep.c:5022
lock_acquire kernel/locking/lockdep.c:5634 [inline]
lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5599
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
_raw_spin_lock_irq+0x32/0x50 kernel/locking/spinlock.c:170
spin_lock_irq include/linux/spinlock.h:374 [inline]
throtl_pending_timer_fn+0xf7/0x1690 block/blk-throttle.c:1152
call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1474
expire_timers kernel/time/timer.c:1519 [inline]
__run_timers.part.0+0x679/0xa80 kernel/time/timer.c:1790
__run_timers kernel/time/timer.c:1768 [inline]
run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1803
__do_softirq+0x29b/0x9c2 kernel/softirq.c:571
invoke_softirq kernel/softirq.c:445 [inline]
__irq_exit_rcu+0x123/0x180 kernel/softirq.c:650
irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1106
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:lock_acquire+0x1ef/0x570 kernel/locking/lockdep.c:5602
Code: 8f a4 7e 83 f8 01 0f 85 e8 02 00 00 9c 58 f6 c4 02 0f 85 fb 02 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24
RSP: 0018:ffffc90004df7b98 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 1ffff920009bef75 RCX: 6e92a25b1ea20f40
RDX: 1ffff11003adc14b RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff9009d887
R10: fffffbfff2013b10 R11: 0000000000000001 R12: 0000000000000002
R13: 0000000000000000 R14: ffffffff8bd855e0 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:269 [inline]
rcu_read_lock include/linux/rcupdate.h:695 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
batadv_nc_worker+0x12d/0xfa0 net/batman-adv/network-coding.c:719
process_one_work+0x996/0x1610 kernel/workqueue.c:2289
worker_thread+0x665/0x1080 kernel/workqueue.c:2436
kthread+0x2e9/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
</TASK>
----------------
Code disassembly (best guess), 1 bytes skipped:
0: a4 movsb %ds:(%rsi),%es:(%rdi)
1: 7e 83 jle 0xffffff86
3: f8 clc
4: 01 0f add %ecx,(%rdi)
6: 85 e8 test %ebp,%eax
8: 02 00 add (%rax),%al
a: 00 9c 58 f6 c4 02 0f add %bl,0xf02c4f6(%rax,%rbx,2)
11: 85 fb test %edi,%ebx
13: 02 00 add (%rax),%al
15: 00 48 83 add %cl,-0x7d(%rax)
18: 7c 24 jl 0x3e
1a: 08 00 or %al,(%rax)
1c: 74 01 je 0x1f
1e: fb sti
1f: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
26: fc ff df
* 29: 48 01 c3 add %rax,%rbx <-- trapping instruction
2c: 48 c7 03 00 00 00 00 movq $0x0,(%rbx)
33: 48 c7 43 08 00 00 00 movq $0x0,0x8(%rbx)
3a: 00
3b: 48 rex.W
3c: 8b .byte 0x8b
3d: 84 .byte 0x84
3e: 24 .byte 0x24