======================================================
WARNING: possible circular locking dependency detected
6.1.16-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.1/3650 is trying to acquire lock:
ffff888147c38920 (&q->queue_lock){..-.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:375 [inline]
ffff888147c38920 (&q->queue_lock){..-.}-{2:2}, at: throtl_pending_timer_fn+0x10d/0x1be0 block/blk-throttle.c:1193
but task is already holding lock:
ffffc900001e0bc0 ((&sq->pending_timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:41 [inline]
ffffc900001e0bc0 ((&sq->pending_timer)){+.-.}-{0:0}, at: call_timer_fn+0xbd/0x840 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}:
lock_acquire+0x23a/0x630 kernel/locking/lockdep.c:5669
del_timer_sync+0x111/0x2e0 kernel/time/timer.c:1417
throtl_pd_free+0x15/0x40 block/blk-throttle.c:493
blkcg_deactivate_policy+0x32d/0x550 block/blk-cgroup.c:1499
blk_throtl_exit+0xa6/0x140 block/blk-throttle.c:2406
disk_release+0x1dd/0x380 block/genhd.c:1171
device_release+0x91/0x1c0
kobject_cleanup lib/kobject.c:681 [inline]
kobject_release lib/kobject.c:712 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x224/0x460 lib/kobject.c:729
do_floppy_init+0x373/0xc59 drivers/block/floppy.c:4758
async_run_entry_fn+0xa2/0x410 kernel/async.c:127
process_one_work+0x909/0x1380 kernel/workqueue.c:2289
worker_thread+0xa5f/0x1210 kernel/workqueue.c:2436
kthread+0x268/0x300 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
-> #1 (&blkcg->lock){....}-{2:2}:
lock_acquire+0x23a/0x630 kernel/locking/lockdep.c:5669
__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:350 [inline]
blkg_create+0xa94/0x1280 block/blk-cgroup.c:336
blkcg_init_disk+0xee/0x350 block/blk-cgroup.c:1260
__alloc_disk_node+0x2ce/0x590 block/genhd.c:1385
__blk_alloc_disk+0x2c/0x80 block/genhd.c:1424
brd_alloc+0x2f9/0x6a0 drivers/block/brd.c:397
brd_init+0x100/0x1c2 drivers/block/brd.c:484
do_one_initcall+0x2d6/0xa80 init/main.c:1303
do_initcall_level+0x157/0x207 init/main.c:1376
do_initcalls+0x49/0x86 init/main.c:1392
kernel_init_freeable+0x473/0x61f init/main.c:1631
kernel_init+0x19/0x290 init/main.c:1519
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
-> #0 (&q->queue_lock){..-.}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3098 [inline]
check_prevs_add kernel/locking/lockdep.c:3217 [inline]
validate_chain+0x1667/0x58e0 kernel/locking/lockdep.c:3832
__lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056
lock_acquire+0x23a/0x630 kernel/locking/lockdep.c:5669
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
_raw_spin_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:170
spin_lock_irq include/linux/spinlock.h:375 [inline]
throtl_pending_timer_fn+0x10d/0x1be0 block/blk-throttle.c:1193
call_timer_fn+0x200/0x840 kernel/time/timer.c:1474
expire_timers kernel/time/timer.c:1519 [inline]
__run_timers+0x67c/0x890 kernel/time/timer.c:1790
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1803
__do_softirq+0x30d/0xb1b kernel/softirq.c:571
invoke_softirq kernel/softirq.c:445 [inline]
__irq_exit_rcu+0x155/0x240 kernel/softirq.c:650
irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1107
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
_raw_spin_lock_irqsave+0x1/0x120 kernel/locking/spinlock.c:161
__debug_check_no_obj_freed lib/debugobjects.c:984 [inline]
debug_check_no_obj_freed+0xc2/0x610 lib/debugobjects.c:1027
slab_free_hook mm/slub.c:1699 [inline]
slab_free_freelist_hook mm/slub.c:1750 [inline]
slab_free mm/slub.c:3661 [inline]
__kmem_cache_free+0x205/0x3c0 mm/slub.c:3674
xt_free_table_info+0x65/0x150 net/netfilter/x_tables.c:1208
__do_replace+0x786/0xa30 net/ipv6/netfilter/ip6_tables.c:1104
do_replace net/ipv6/netfilter/ip6_tables.c:1157 [inline]
do_ip6t_set_ctl+0x2d9c/0x3f50 net/ipv6/netfilter/ip6_tables.c:1639
nf_setsockopt+0x28a/0x2b0 net/netfilter/nf_sockopt.c:101
__sys_setsockopt+0x57e/0xa00 net/socket.c:2252
__do_sys_setsockopt net/socket.c:2263 [inline]
__se_sys_setsockopt net/socket.c:2260 [inline]
__x64_sys_setsockopt+0xb1/0xc0 net/socket.c:2260
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
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 ***
1 lock held by syz-executor.1/3650:
#0: ffffc900001e0bc0 ((&sq->pending_timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:41 [inline]
#0: ffffc900001e0bc0 ((&sq->pending_timer)){+.-.}-{0:0}, at: call_timer_fn+0xbd/0x840 kernel/time/timer.c:1464
stack backtrace:
CPU: 1 PID: 3650 Comm: syz-executor.1 Not tainted 6.1.16-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
check_noncircular+0x2fa/0x3b0 kernel/locking/lockdep.c:2178
check_prev_add kernel/locking/lockdep.c:3098 [inline]
check_prevs_add kernel/locking/lockdep.c:3217 [inline]
validate_chain+0x1667/0x58e0 kernel/locking/lockdep.c:3832
__lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056
lock_acquire+0x23a/0x630 kernel/locking/lockdep.c:5669
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
_raw_spin_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:170
spin_lock_irq include/linux/spinlock.h:375 [inline]
throtl_pending_timer_fn+0x10d/0x1be0 block/blk-throttle.c:1193
call_timer_fn+0x200/0x840 kernel/time/timer.c:1474
expire_timers kernel/time/timer.c:1519 [inline]
__run_timers+0x67c/0x890 kernel/time/timer.c:1790
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1803
__do_softirq+0x30d/0xb1b kernel/softirq.c:571
invoke_softirq kernel/softirq.c:445 [inline]
__irq_exit_rcu+0x155/0x240 kernel/softirq.c:650
irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1107
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:_raw_spin_lock_irqsave+0x1/0x120 kernel/locking/spinlock.c:161
Code: c9 41 b8 01 00 00 00 45 31 c9 ff 74 24 08 e8 96 c4 d6 f6 48 83 c4 08 48 89 df 5b e9 19 24 d8 f6 66 0f 1f 84 00 00 00 00 00 55 <48> 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 83 ec 60 49 89
RSP: 0018:ffffc90004e4f770 EFLAGS: 00000202
RAX: 000000000001d240 RBX: 0000000000000000 RCX: 61c8864680b583eb
RDX: dffffc0000000000 RSI: ffff888053240e10 RDI: ffffffff91d719c8
RBP: ffffffff91d719c0 R08: ffffffff813dcf88 R09: fffffbfff19fca5d
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888053240000
R13: ffff888053240e00 R14: 0000000000000000 R15: 0000000000000001
__debug_check_no_obj_freed lib/debugobjects.c:984 [inline]
debug_check_no_obj_freed+0xc2/0x610 lib/debugobjects.c:1027
slab_free_hook mm/slub.c:1699 [inline]
slab_free_freelist_hook mm/slub.c:1750 [inline]
slab_free mm/slub.c:3661 [inline]
__kmem_cache_free+0x205/0x3c0 mm/slub.c:3674
xt_free_table_info+0x65/0x150 net/netfilter/x_tables.c:1208
__do_replace+0x786/0xa30 net/ipv6/netfilter/ip6_tables.c:1104
do_replace net/ipv6/netfilter/ip6_tables.c:1157 [inline]
do_ip6t_set_ctl+0x2d9c/0x3f50 net/ipv6/netfilter/ip6_tables.c:1639
nf_setsockopt+0x28a/0x2b0 net/netfilter/nf_sockopt.c:101
__sys_setsockopt+0x57e/0xa00 net/socket.c:2252
__do_sys_setsockopt net/socket.c:2263 [inline]
__se_sys_setsockopt net/socket.c:2260 [inline]
__x64_sys_setsockopt+0xb1/0xc0 net/socket.c:2260
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7efc2608d74a
Code: 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 36 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff67f6f9e8 EFLAGS: 00000202 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000029 RCX: 00007efc2608d74a
RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000003
RBP: 00007fff67f6fa10 R08: 00000000000003b8 R09: ffffffffff000000
R10: 00007efc26183bc0 R11: 0000000000000202 R12: 00007fff67f6fa70
R13: 0000000000000003 R14: 00007fff67f6fa0c R15: 00007efc26183b60
----------------
Code disassembly (best guess):
0: c9 leaveq
1: 41 b8 01 00 00 00 mov $0x1,%r8d
7: 45 31 c9 xor %r9d,%r9d
a: ff 74 24 08 pushq 0x8(%rsp)
e: e8 96 c4 d6 f6 callq 0xf6d6c4a9
13: 48 83 c4 08 add $0x8,%rsp
17: 48 89 df mov %rbx,%rdi
1a: 5b pop %rbx
1b: e9 19 24 d8 f6 jmpq 0xf6d82439
20: 66 0f 1f 84 00 00 00 nopw 0x0(%rax,%rax,1)
27: 00 00
29: 55 push %rbp
* 2a: 48 89 e5 mov %rsp,%rbp <-- trapping instruction
2d: 41 57 push %r15
2f: 41 56 push %r14
31: 41 55 push %r13
33: 41 54 push %r12
35: 53 push %rbx
36: 48 83 e4 e0 and $0xffffffffffffffe0,%rsp
3a: 48 83 ec 60 sub $0x60,%rsp
3e: 49 rex.WB
3f: 89 .byte 0x89