======================================================
WARNING: possible circular locking dependency detected
6.1.16-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.0/3646 is trying to acquire lock:
ffff88802201dc40 (&q->queue_lock){..-.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:375 [inline]
ffff88802201dc40 (&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_mq_alloc_disk+0x11e/0x1e0 block/blk-mq.c:4081
floppy_alloc_disk+0x54/0x360 drivers/block/floppy.c:4514
do_floppy_init+0x1af/0xc59 drivers/block/floppy.c:4595
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
-> #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
_copy_from_user+0x2/0x170 lib/usercopy.c:12
copy_from_user include/linux/uaccess.h:161 [inline]
copy_from_sockptr_offset include/linux/sockptr.h:48 [inline]
copy_from_sockptr include/linux/sockptr.h:55 [inline]
do_replace net/ipv6/netfilter/ip6_tables.c:1131 [inline]
do_ip6t_set_ctl+0x2c2/0x3f50 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.0/3646:
#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: 3646 Comm: syz-executor.0 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:_copy_from_user+0x2/0x170 lib/usercopy.c:12
Code: c7 80 cf 3c 8b e8 9e 72 18 fd 0f 0b eb 89 89 d9 80 e1 07 80 c1 03 38 c1 7c c2 48 89 df e8 46 8e a6 fd eb b8 cc cc cc cc 41 57 <41> 56 41 54 53 49 89 d4 49 89 f7 49 89 fe e8 eb 29 50 fd 48 c7 c7
RSP: 0018:ffffc90004c2f9d0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000060 RSI: 00007fbdb2585000 RDI: ffffc90004c2fb70
RBP: ffffc90004c2fd70 R08: ffffffff89622188 R09: ffffc90004c2fb70
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888051d10000
R13: 0000000000000000 R14: ffffc90004c2fb70 R15: 0000000000000000
copy_from_user include/linux/uaccess.h:161 [inline]
copy_from_sockptr_offset include/linux/sockptr.h:48 [inline]
copy_from_sockptr include/linux/sockptr.h:55 [inline]
do_replace net/ipv6/netfilter/ip6_tables.c:1131 [inline]
do_ip6t_set_ctl+0x2c2/0x3f50 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: 0033:0x7fbdb248d74a
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:00007ffe81e4ddb8 EFLAGS: 00000206 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000029 RCX: 00007fbdb248d74a
RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000003
RBP: 00007ffe81e4dde0 R08: 00000000000002e8 R09: ffffffffff000000
R10: 00007fbdb2585000 R11: 0000000000000206 R12: 00007ffe81e4de40
R13: 0000000000000003 R14: 00007ffe81e4dddc R15: 00007fbdb2584fa0
----------------
Code disassembly (best guess):
0: c7 80 cf 3c 8b e8 9e movl $0xfd18729e,-0x1774c331(%rax)
7: 72 18 fd
a: 0f 0b ud2
c: eb 89 jmp 0xffffff97
e: 89 d9 mov %ebx,%ecx
10: 80 e1 07 and $0x7,%cl
13: 80 c1 03 add $0x3,%cl
16: 38 c1 cmp %al,%cl
18: 7c c2 jl 0xffffffdc
1a: 48 89 df mov %rbx,%rdi
1d: e8 46 8e a6 fd callq 0xfda68e68
22: eb b8 jmp 0xffffffdc
24: cc int3
25: cc int3
26: cc int3
27: cc int3
28: 41 57 push %r15
* 2a: 41 56 push %r14 <-- trapping instruction
2c: 41 54 push %r12
2e: 53 push %rbx
2f: 49 89 d4 mov %rdx,%r12
32: 49 89 f7 mov %rsi,%r15
35: 49 89 fe mov %rdi,%r14
38: e8 eb 29 50 fd callq 0xfd502a28
3d: 48 rex.W
3e: c7 .byte 0xc7
3f: c7 .byte 0xc7