rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1 GPs behind) idle=9fbc/1/0x4000000000000000 softirq=18980/18981 fqs=5248
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:  1100335          0            0
rcu: 	cputime:    25330      27159           85   ==> 52500(ms)
rcu: 	(t=10502 jiffies g=11673 q=2800 ncpus=2)
CPU: 0 UID: 0 PID: 6975 Comm: syz.0.467 Not tainted 6.16.0-rc6-syzkaller-00411-g95993dc3039e #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:rcu_read_unlock_special+0x87/0x4c0
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 62 2c f8 10 41 f7 c6 00 00 f0 00 74 49 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc90000007440 EFLAGS: 00000206
RAX: ebdb0b24fca2e100 RBX: 1ffff92000000e90 RCX: ebdb0b24fca2e100
RDX: 0000000000000002 RSI: ffffffff8d998836 RDI: ffffffff8be29f40
RBP: ffffc90000007538 R08: ffffffff8fa1e8f7 R09: 1ffffffff1f43d1e
R10: dffffc0000000000 R11: fffffbfff1f43d1f R12: ffffffff8e144400
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
FS:  00007fd0f57626c0(0000) GS:ffff8880b861f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffd000000 CR3: 0000000106c74000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __rcu_read_unlock+0x84/0xe0
 unwind_next_frame+0x19ae/0x2390
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 __kasan_slab_alloc+0x6c/0x80
 kmem_cache_alloc_node_noprof+0x1bb/0x3c0
 kmalloc_reserve+0xbd/0x290
 __alloc_skb+0x142/0x2d0
 lapb_send_control+0x38/0x3e0
 lapb_t1timer_expiry+0x699/0xab0
 call_timer_fn+0x17e/0x5f0
 __run_timer_base+0x61a/0x860
 run_timer_softirq+0xb7/0x180
 handle_softirqs+0x286/0x870
 __irq_exit_rcu+0xca/0x1f0
 irq_exit_rcu+0x9/0x30
 sysvec_irq_work+0xa3/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_irq_work+0x1a/0x20
RIP: 0010:finish_task_switch+0x26b/0x950
Code: 0f 84 3c 01 00 00 48 85 db 0f 85 63 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 0f 1a df 09 e8 ba b9 35 00 fb 4c 8b 65 c0 <49> 8d bc 24 18 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc900029dfa38 EFLAGS: 00000282
RAX: ebdb0b24fca2e100 RBX: 0000000000000000 RCX: ebdb0b24fca2e100
RDX: 0000000000000000 RSI: ffffffff8d998836 RDI: ffffffff8be29f40
RBP: ffffc900029dfa90 R08: ffffffff8fa1e8f7 R09: 1ffffffff1f43d1e
R10: dffffc0000000000 R11: fffffbfff1f43d1f R12: ffff88801f5d5640
R13: dffffc0000000000 R14: ffff88801ebc5640 R15: ffff88804b03ab98
 __schedule+0x16fd/0x4d00
 preempt_schedule_irq+0xb5/0x150
 irqentry_exit+0x6f/0x90
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:lock_acquire+0x175/0x360
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 9b d3 01 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc900029dfe20 EFLAGS: 00000206
RAX: ebdb0b24fca2e100 RBX: 0000000000000000 RCX: ebdb0b24fca2e100
RDX: 0000000000000001 RSI: ffffffff8db86553 RDI: ffffffff8be29f40
RBP: ffffffff81ab1398 R08: 0000000000000000 R09: ffffffff81ab1398
R10: dffffc0000000000 R11: fffff5200053bf91 R12: 0000000000000002
R13: ffffffff8e13f2c0 R14: 0000000000000000 R15: 0000000000000246
 syscall_exit_work+0x165/0x1d0
 do_syscall_64+0x2ad/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd0f498e9a9
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:00007fd0f5762038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: 0000000000000006 RBX: 00007fd0f4bb6080 RCX: 00007fd0f498e9a9
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000180
RBP: 00007fd0f4a10d69 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fd0f4bb6080 R15: 00007fff7a7056b8
 </TASK>
sched: DL replenish lagged too much
