rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (1 GPs behind) idle=3ae4/1/0x4000000000000000 softirq=26409/26410 fqs=5248
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:   990499          0            0
rcu: 	cputime:    33903      18586           93   ==> 52500(ms)
rcu: 	(t=10501 jiffies g=17989 q=6976 ncpus=2)
CPU: 1 UID: 0 PID: 8566 Comm: syz.1.806 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:handle_softirqs+0x1b0/0x870
Code: 89 64 24 30 0f b7 db 48 c7 c7 20 a7 89 8b e8 b7 76 f4 09 65 66 c7 05 65 54 1b 11 00 00 e8 08 6a 42 00 fb 49 c7 c7 c0 c0 e0 8d <b8> ff ff ff ff 0f bc c3 41 89 c5 41 ff c5 0f 84 c2 03 00 00 89 5c
RSP: 0018:ffffc900001e0e40 EFLAGS: 00000286
RAX: 550fe6c7c617de00 RBX: 0000000000000282 RCX: 550fe6c7c617de00
RDX: 0000000000000003 RSI: ffffffff8d9b6adf RDI: ffffffff8be33300
RBP: ffffc900001e0f50 R08: ffffffff8fa38137 R09: 1ffffffff1f47026
R10: dffffc0000000000 R11: fffffbfff1f47027 R12: 000000000000000a
R13: 0000000000000000 R14: dffffc0000000000 R15: ffffffff8de0c0c0
FS:  00007f2c462466c0(0000) GS:ffff8881a3c1c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8d05f056c0 CR3: 0000000104db6000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __irq_exit_rcu+0xca/0x1f0
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:preempt_schedule_irq+0xb0/0x150
Code: 24 20 f6 44 24 21 02 74 0c 90 0f 0b 48 f7 03 08 00 00 00 74 64 bf 01 00 00 00 e8 fb 88 15 f6 e8 36 e3 4c f6 fb bf 01 00 00 00 <e8> 5b ab ff ff 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 8b 44 24
RSP: 0018:ffffc9000702fb20 EFLAGS: 00000282
RAX: 550fe6c7c617de00 RBX: 0000000000000000 RCX: 550fe6c7c617de00
RDX: 0000000000000007 RSI: ffffffff8d9b6adf RDI: 0000000000000001
RBP: ffffc9000702fbd0 R08: ffffffff8fa38137 R09: 1ffffffff1f47026
R10: dffffc0000000000 R11: fffffbfff1f47027 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000e05f64
 irqentry_exit+0x6f/0x90
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:qlist_free_all+0x6d/0x140
Code: 4c 04 08 f6 c1 01 75 53 49 01 c4 0f 1f 44 00 00 41 0f b6 44 24 33 c1 e0 18 3d 00 00 00 f5 4d 0f 45 e5 4d 8b 64 24 08 49 8b 2f <49> 63 84 24 c0 00 00 00 49 29 c7 4c 89 e7 4c 89 fe e8 bd e3 ff ff
RSP: 0018:ffffc9000702fc90 EFLAGS: 00000246
RAX: 00000000f5000000 RBX: ffffc9000702fcc8 RCX: ffff88810000f140
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888028ca6a80 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f47027 R12: ffff88810000f140
R13: 0000000000000000 R14: 0000000000000000 R15: ffff88810a3911f8
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 kmem_cache_alloc_noprof+0x1c1/0x3c0
 getname_flags+0xb8/0x540
 do_sys_openat2+0xbc/0x1c0
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2c4538eba9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2c46246038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f2c455d5fa0 RCX: 00007f2c4538eba9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffffffff9c
RBP: 00007f2c45411e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2c455d6038 R14: 00007f2c455d5fa0 R15: 00007ffdf44de2e8
 </TASK>
