rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10500 ticks this GP) idle=fc9c/1/0x4000000000000000 softirq=63161/63161 fqs=281
rcu: 	(t=10501 jiffies g=53865 q=385 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 9938 jiffies! g53865 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=21300
rcu: rcu_preempt kthread starved for 9940 jiffies! g53865 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:26632 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 __schedule+0x1737/0x4d30
 schedule+0x165/0x360
 schedule_timeout+0x12b/0x270
 rcu_gp_fqs_loop+0x301/0x1540
 rcu_gp_kthread+0x99/0x390
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5754 Comm: sshd Not tainted 6.16.0-syzkaller-06600-g1dbf1d590d10-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:native_queued_spin_lock_slowpath+0xb7/0x8e0
Code: 00 00 00 0f 1f 44 00 00 4c 8d 74 24 60 49 89 df 49 c1 ef 03 41 bd 01 00 00 00 eb 06 89 44 24 60 f3 90 48 89 df be 04 00 00 00 <e8> 54 66 b0 f6 48 b8 00 00 00 00 00 fc ff df 41 0f b6 04 07 84 c0
RSP: 0018:ffffc900032af8e0 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffff8881132b35c0 RCX: ffffffff8b726fbc
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8881132b35c0
RBP: ffffc900032af9d8 R08: ffff8881132b35c3 R09: 1ffff110226566b8
R10: dffffc0000000000 R11: ffffed10226566b9 R12: 1ffff92000655f24
R13: 0000000000000001 R14: ffffc900032af940 R15: 1ffff110226566b8
FS:  00007f6cdad83800(0000) GS:ffff8881a3c80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555b2fe5c8 CR3: 0000000027ab4000 CR4: 00000000000006f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 queued_spin_lock_slowpath+0x43/0x50
 do_raw_spin_lock+0x21f/0x290
 lock_sock_nested+0x6a/0x100
 tcp_sendmsg+0x21/0x50
 __sock_sendmsg+0x19c/0x270
 sock_write_iter+0x258/0x330
 vfs_write+0x54b/0xa90
 ksys_write+0x145/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6cda916bf2
Code: 89 c7 48 89 44 24 08 e8 7b 34 fa ff 48 8b 44 24 08 48 83 c4 28 c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 6f 48 8b 15 07 a2 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffc8d4e6158 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000056434e369360 RCX: 00007f6cda916bf2
RDX: 0000000000000038 RSI: 000056434e389da0 RDI: 0000000000000007
RBP: 000056434e389da0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000038
R13: 000056434e368290 R14: 000056434e359130 R15: 000056434e369d70
 </TASK>
CPU: 0 UID: 0 PID: 14526 Comm: syz.0.2242 Not tainted 6.16.0-syzkaller-06600-g1dbf1d590d10-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 b2 e8 f2 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:ffffc90000007480 EFLAGS: 00000206
RAX: be2d190e1a6fd000 RBX: 1ffff92000000e98 RCX: be2d190e1a6fd000
RDX: 0000000000000002 RSI: ffffffff8d9792dd RDI: ffffffff8be30a00
RBP: ffffc90000007578 R08: ffffffff8fa07bf7 R09: 1ffffffff1f40f7e
R10: dffffc0000000000 R11: fffffbfff1f40f7f R12: ffffffff8e141800
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
FS:  00007f5d482446c0(0000) GS:ffff8880b8680000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000001153b8000 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
 __alloc_skb+0x112/0x2d0
 __tcp_send_ack+0xaf/0x620
 tcp_delack_timer_handler+0x366/0x530
 tcp_delack_timer+0x205/0x3b0
 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:call_function_single_prep_ipi+0x0/0x1f0
Code: 4c 89 f5 0f 84 d6 f8 ff ff 48 8b 3c 24 e8 08 14 30 00 e9 c8 f8 ff ff 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48
RSP: 0018:ffffc90008337418 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0000000000000002
RDX: ffff888034680000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: ffffc900083375a0 R08: ffff88804b03b197 R09: 1ffff11009607632
R10: dffffc0000000000 R11: ffffed1009607633 R12: ffff88804b03b180
R13: dffffc0000000000 R14: 1ffff11026cc7f01 R15: 0000000000000000
 smp_call_function_many_cond+0xa76/0x12d0
 on_each_cpu_cond_mask+0x3f/0x80
 smp_text_poke_batch_finish+0x5f9/0x1130
 __static_call_transform+0x4eb/0x750
 arch_static_call_transform+0x98/0xc0
 __static_call_update+0xe4/0x5d0
 tracepoint_add_func+0x91e/0xa10
 tracepoint_probe_register+0x5d/0x90
 perf_trace_event_init+0x4e1/0x9d0
 perf_trace_init+0x23d/0x2d0
 perf_tp_event_init+0x8d/0x120
 perf_try_init_event+0x17f/0x870
 perf_event_alloc+0x1357/0x2b80
 __se_sys_perf_event_open+0x772/0x1d70
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5d4738ebe9
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:00007f5d48244038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f5d475b5fa0 RCX: 00007f5d4738ebe9
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000180
RBP: 00007f5d47411e19 R08: 000000000000000a R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5d475b6038 R14: 00007f5d475b5fa0 R15: 00007ffe89d68188
 </TASK>
sched: DL replenish lagged too much
