=============================
WARNING: suspicious RCU usage
6.10.0-rc2-syzkaller-00022-g32f88d65f01b #0 Not tainted
-----------------------------
net/bridge/br_private.h:1599 suspicious rcu_dereference_protected() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
5 locks held by kswapd0/111:
#0: ffffffff8dd3a9a0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0xa88/0x1970 mm/vmscan.c:6924
#1: ffffffff8dbb5160 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
#1: ffffffff8dbb5160 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
#1: ffffffff8dbb5160 (rcu_read_lock){....}-{1:2}, at: list_lru_count_one+0x3a/0x320 mm/list_lru.c:171
#2: ffffc90000598cb0 ((&p->forward_delay_timer)){+.-.}-{0:0}, at: call_timer_fn+0x11a/0x610 kernel/time/timer.c:1789
#3: ffff88801d880cb8 (&br->lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#3: ffff88801d880cb8 (&br->lock){+.-.}-{2:2}, at: br_forward_delay_timer_expired+0x4f/0x560 net/bridge/br_stp_timer.c:86
#4: ffffffff8dbb5160 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
#4: ffffffff8dbb5160 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
#4: ffffffff8dbb5160 (rcu_read_lock){....}-{1:2}, at: br_mst_set_state+0x114/0x750 net/bridge/br_mst.c:105
stack backtrace:
CPU: 1 PID: 111 Comm: kswapd0 Not tainted 6.10.0-rc2-syzkaller-00022-g32f88d65f01b #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:114
lockdep_rcu_suspicious+0x20b/0x3b0 kernel/locking/lockdep.c:6712
nbp_vlan_group net/bridge/br_private.h:1599 [inline]
br_mst_set_state+0x5c8/0x750 net/bridge/br_mst.c:106
br_set_state+0x542/0x880 net/bridge/br_stp.c:47
br_forward_delay_timer_expired+0x312/0x560 net/bridge/br_stp_timer.c:88
call_timer_fn+0x1a0/0x610 kernel/time/timer.c:1792
expire_timers kernel/time/timer.c:1843 [inline]
__run_timers+0x74b/0xaf0 kernel/time/timer.c:2417
__run_timer_base kernel/time/timer.c:2428 [inline]
__run_timer_base kernel/time/timer.c:2421 [inline]
run_timer_base+0x111/0x190 kernel/time/timer.c:2437
run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2447
handle_softirqs+0x216/0x8f0 kernel/softirq.c:554
__do_softirq kernel/softirq.c:588 [inline]
invoke_softirq kernel/softirq.c:428 [inline]
__irq_exit_rcu kernel/softirq.c:637 [inline]
irq_exit_rcu+0xbb/0x120 kernel/softirq.c:649
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x3ba/0x6c0 kernel/locking/lockdep.c:5762
Code: 7e 83 f8 01 0f 85 f5 01 00 00 9c 58 f6 c4 02 0f 85 e0 01 00 00 48 f7 04 24 00 02 00 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c5 48 c7 45 00 00 00 00 00 c7 45 08 00 00 00 00 48 8b 84 24
RSP: 0018:ffffc90001137588 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 20341b884a02928f RCX: ffffc900011375d8
RDX: 1ffff110036bb15a RSI: ffffffff8b2cbbc0 RDI: ffffffff8b8fbfa0
RBP: 1ffff92000226eb3 R08: 0000000000000000 R09: fffffbfff1fc5812
R10: ffffffff8fe2c097 R11: 0000000000000002 R12: 0000000000000002
R13: 0000000000000003 R14: ffff88801b5d8ad8 R15: ffff88801b5d8000
rcu_lock_release include/linux/rcupdate.h:339 [inline]
rcu_read_unlock include/linux/rcupdate.h:812 [inline]
xa_load+0x14f/0x2c0 lib/xarray.c:1481
list_lru_from_memcg_idx mm/list_lru.c:56 [inline]
list_lru_from_memcg_idx mm/list_lru.c:53 [inline]
list_lru_count_one+0x1bb/0x320 mm/list_lru.c:172
list_lru_shrink_count include/linux/list_lru.h:156 [inline]
super_cache_count+0x175/0x300 fs/super.c:263
do_shrink_slab+0x82/0x11c0 mm/shrinker.c:382
shrink_slab_memcg mm/shrinker.c:548 [inline]
shrink_slab+0xa87/0x1310 mm/shrinker.c:626
shrink_one+0x493/0x7c0 mm/vmscan.c:4790
shrink_many mm/vmscan.c:4851 [inline]
lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951
shrink_node mm/vmscan.c:5910 [inline]
kswapd_shrink_node mm/vmscan.c:6720 [inline]
balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911
kswapd+0x5ea/0xbf0 mm/vmscan.c:7180
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
bridge0: port 1(bridge_slave_0) entered learning state
----------------
Code disassembly (best guess):
0: 7e 83 jle 0xffffff85
2: f8 clc
3: 01 0f add %ecx,(%rdi)
5: 85 f5 test %esi,%ebp
7: 01 00 add %eax,(%rax)
9: 00 9c 58 f6 c4 02 0f add %bl,0xf02c4f6(%rax,%rbx,2)
10: 85 e0 test %esp,%eax
12: 01 00 add %eax,(%rax)
14: 00 48 f7 add %cl,-0x9(%rax)
17: 04 24 add $0x24,%al
19: 00 02 add %al,(%rdx)
1b: 00 00 add %al,(%rax)
1d: 74 01 je 0x20
1f: fb sti
20: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
27: fc ff df
* 2a: 48 01 c5 add %rax,%rbp <-- trapping instruction
2d: 48 c7 45 00 00 00 00 movq $0x0,0x0(%rbp)
34: 00
35: c7 45 08 00 00 00 00 movl $0x0,0x8(%rbp)
3c: 48 rex.W
3d: 8b .byte 0x8b
3e: 84 .byte 0x84
3f: 24 .byte 0x24