rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1 GPs behind) idle=0424/1/0x4000000000000000 softirq=22487/22488 fqs=4712
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:   969805          0            0
rcu: 	cputime:    24308      28181           94   ==> 52490(ms)
rcu: 	(t=10500 jiffies g=15761 q=2369 ncpus=2)
CPU: 0 UID: 0 PID: 7998 Comm: syz.1.622 Not tainted 6.16.0-rc6-syzkaller-00411-g95993dc3039e-dirty #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:ffffc900000074a0 EFLAGS: 00000206
RAX: 5a678c308f1a2400 RBX: 1ffff92000000e9c RCX: 5a678c308f1a2400
RDX: 0000000000000002 RSI: ffffffff8d998940 RDI: ffffffff8be29f40
RBP: ffffc90000007598 R08: ffffffff8fa1e9f7 R09: 1ffffffff1f43d3e
R10: dffffc0000000000 R11: fffffbfff1f43d3f R12: ffffffff8e144400
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
FS:  00007fbf8491b6c0(0000) GS:ffff8880b861f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000e28000 CR3: 00000001088ce000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000082
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
 __alloc_skb+0x112/0x2d0
 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_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:___slab_alloc+0xa4e/0x1480
Code: 24 60 00 00 00 00 9c 8f 44 24 60 f7 44 24 60 00 02 00 00 0f 85 9c 08 00 00 f7 c5 00 02 00 00 74 01 fb 65 48 8b 05 12 36 87 10 <48> 3b 44 24 68 0f 85 e9 08 00 00 4c 89 f8 48 83 c4 70 5b 41 5c 41
RSP: 0018:ffffc9000a5e7c18 EFLAGS: 00000206
RAX: 5a678c308f1a2400 RBX: ffff88804b040a50 RCX: 5a678c308f1a2400
RDX: 0000000000000000 RSI: ffffffff8d998940 RDI: ffffffff8be29f40
RBP: 0000000000000282 R08: ffffffff8fa1e9f7 R09: 1ffffffff1f43d3e
R10: dffffc0000000000 R11: fffffbfff1f43d3f R12: ffff88804b040a50
R13: ffff88801b68fa00 R14: 0000000000000000 R15: ffff888109356800
 kmem_cache_alloc_noprof+0x283/0x3c0
 alloc_empty_file+0x55/0x1d0
 alloc_file_pseudo+0x13d/0x210
 sock_alloc_file+0xb8/0x2e0
 __sys_socketpair+0x2db/0x560
 __x64_sys_socketpair+0x9b/0xb0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbf83b8e9a9
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:00007fbf8491b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007fbf83db6080 RCX: 00007fbf83b8e9a9
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000001
RBP: 00007fbf83c10d69 R08: 0000000000000000 R09: 0000000000000000
R10: 00002000000029c0 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fbf83db6080 R15: 00007ffed81fee18
 </TASK>
sched: DL replenish lagged too much
