rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10500 ticks this GP) idle=81b4/1/0x4000000000000000 softirq=21186/21186 fqs=0
rcu: 	(t=10500 jiffies g=10577 q=1666 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g10577 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=5046
rcu: rcu_preempt kthread starved for 10500 jiffies! g10577 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
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:26536 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 __schedule+0x16f5/0x4d00
 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>
CPU: 0 UID: 0 PID: 7605 Comm: syz.2.793 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:ffffc90000007480 EFLAGS: 00000206
RAX: 16ab6c3038acb700 RBX: 1ffff92000000e98 RCX: 16ab6c3038acb700
RDX: 0000000000000002 RSI: ffffffff8d998836 RDI: ffffffff8be29f40
RBP: ffffc90000007578 R08: ffffffff8fa1e8f7 R09: 1ffffffff1f43d1e
R10: dffffc0000000000 R11: fffffbfff1f43d1f R12: ffffffff8e144400
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
FS:  00007f8f523d56c0(0000) GS:ffff8880b861f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8f523d4fc8 CR3: 0000000028ccc000 CR4: 00000000000006f0
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:memset_orig+0x7/0xb0
Code: 89 d1 f3 aa 4c 89 c8 e9 57 b6 02 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 49 89 fa 40 0f b6 ce <48> b8 01 01 01 01 01 01 01 01 48 0f af c1 41 89 f9 41 83 e1 07 75
RSP: 0018:ffffc9000658fc18 EFLAGS: 00000246
RAX: 0000000000000137 RBX: ffff88802b4b5318 RCX: 0000000000000000
RDX: 0000000000000027 RSI: 0000000000000000 RDI: ffffed1005696a63
RBP: 0000000000000cc0 R08: ffffffff8fa1e8f7 R09: 1ffffffff1f43d1e
R10: ffffed1005696a63 R11: fffffbfff1f43d1f R12: ffff88802b4b5318
R13: 0000000000000138 R14: 0000000000000138 R15: dffffc0000000000
 kasan_unpoison+0x48/0x70
 __kasan_slab_alloc+0x58/0x80
 kmem_cache_alloc_lru_noprof+0x1c6/0x3d0
 __d_alloc+0x31/0x6f0
 d_alloc_pseudo+0x1f/0xb0
 alloc_file_pseudo+0xcc/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: 0033:0x7f8f5458e9a9
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:00007f8f523d5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007f8f547b6080 RCX: 00007f8f5458e9a9
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 000000000000001e
RBP: 00007f8f54610d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000200 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f8f547b6080 R15: 00007ffd3a961138
 </TASK>
sched: DL replenish lagged too much
