rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 ticks this GP) idle=1e5c/1/0x4000000000000002 softirq=28112/28112 fqs=0
	(detected by 1, t=10502 jiffies, g=29825, q=2108 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 10902 Comm: syz.3.3040 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:mark_lock+0x1/0x320 kernel/locking/lockdep.c:4589
Code: c1 7c 90 48 c7 c7 e8 a9 1f 8e e8 8a 47 6d 00 4c 89 f7 41 89 d9 e9 79 ff ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 <41> 57 41 56 41 55 41 54 53 50 89 d5 49 89 f6 48 89 fb 49 bd 00 00
RSP: 0018:ffffc90000006bb0 EFLAGS: 00000046
RAX: 0000000000000006 RBX: 0000000000000006 RCX: 0000000000000002
RDX: 0000000000000008 RSI: ffff88807dc9e510 RDI: ffff88807dc9d940
RBP: ffffc90000006e10 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: ffff88807dc9d940
R13: 0000000000000002 R14: ffff88807dc9e510 R15: ffff88807dc9e530
FS:  00007f96e6f816c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000001d6b1000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 mark_usage kernel/locking/lockdep.c:4549 [inline]
 __lock_acquire+0xd6f/0x7c50 kernel/locking/lockdep.c:5003
 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 __task_pid_nr_ns+0x44/0x460 kernel/pid.c:497
 perf_event_pid_type kernel/events/core.c:1361 [inline]
 perf_event_tid kernel/events/core.c:1375 [inline]
 __perf_event_header__init_id+0x222/0x530 kernel/events/core.c:7016
 perf_prepare_sample+0x18b/0x2040 kernel/events/core.c:7536
 __perf_event_output kernel/events/core.c:7730 [inline]
 perf_event_output_forward+0x163/0x2a0 kernel/events/core.c:7750
 __perf_event_overflow+0x448/0x610 kernel/events/core.c:9496
 perf_tp_event+0x335/0xb60 kernel/events/core.c:10029
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10002
 perf_trace_preemptirq_template+0x287/0x330 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0xd3/0x140 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x24/0x40 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:rcu_read_unlock_special+0x84/0x500 kernel/rcu/tree_plugin.h:685
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 2d 97 96 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc90000007720 EFLAGS: 00000206
RAX: ee6d1c15b8aa6900 RBX: 1ffff92000000eec RCX: ee6d1c15b8aa6900
RDX: dffffc0000000000 RSI: ffffffff8a8c0500 RDI: ffffffff8adefca0
RBP: ffffc90000007818 R08: dffffc0000000000 R09: fffffbfff215c45a
R10: fffffbfff215c45a R11: 1ffffffff215c459 R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8e3b900 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 __ip_queue_xmit+0x10b1/0x19b0 net/ipv4/ip_output.c:533
 __tcp_transmit_skb+0x1c6c/0x3160 net/ipv4/tcp_output.c:1405
 tcp_delack_timer_handler+0x2a9/0x440 net/ipv4/tcp_timer.c:322
 tcp_delack_timer+0x188/0x2e0 net/ipv4/tcp_timer.c:345
 call_timer_fn+0x1a0/0x670 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1549 [inline]
 __run_timers+0x525/0x7c0 kernel/time/timer.c:1820
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1833
 handle_softirqs+0x2a1/0x920 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194
Code: 74 05 e8 fe d1 65 f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 66 5b 36 f7 65 8b 05 67 14 e1 75 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc90005a17d00 EFLAGS: 00000206
RAX: ee6d1c15b8aa6900 RBX: 0000000000000a06 RCX: ee6d1c15b8aa6900
RDX: dffffc0000000000 RSI: ffffffff8a8c0500 RDI: 0000000000000001
RBP: ffffc90005a17d90 R08: dffffc0000000000 R09: fffffbfff215c46c
R10: fffffbfff215c46c R11: 1ffffffff215c46b R12: dffffc0000000000
R13: 0000000000000000 R14: ffff888073d9c008 R15: 1ffff92000b42fa0
 __do_sys_perf_event_open kernel/events/core.c:12785 [inline]
 __se_sys_perf_event_open+0x124f/0x1e60 kernel/events/core.c:12378
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f96e618eba9
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:00007f96e6f81038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f96e63d5fa0 RCX: 00007f96e618eba9
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000480
RBP: 00007f96e6211e19 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f96e63d6038 R14: 00007f96e63d5fa0 R15: 00007ffd9f68f3c8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g29825 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=10017
rcu: rcu_preempt kthread starved for 10502 jiffies! g29825 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:27200 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 10902 Comm: syz.3.3040 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:asm_sysvec_irq_work+0x0/0x20 arch/x86/include/asm/idtentry.h:722
Code: e9 b5 03 00 00 90 90 90 90 90 0f 01 ca fc 6a ff e8 b5 02 00 00 48 89 c4 48 89 e7 e8 4a 0e d7 ff e9 95 03 00 00 90 90 90 90 90 <0f> 01 ca fc 6a ff e8 95 02 00 00 48 89 c4 48 89 e7 e8 1a 13 d7 ff
RSP: 0018:ffffc900000076f8 EFLAGS: 00000006
RAX: ee6d1c15b8aa6900 RBX: 1ffff92000000eec RCX: ee6d1c15b8aa6900
RDX: dffffc0000000000 RSI: ffffffff8a8c0500 RDI: ffffffff8adefca0
RBP: ffffc90000007818 R08: dffffc0000000000 R09: fffffbfff215c45a
R10: fffffbfff215c45a R11: 1ffffffff215c459 R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8e3b900 R15: 0000000000000001
FS:  00007f96e6f816c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000001d6b1000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
RIP: 0010:rcu_read_unlock_special+0x84/0x500 kernel/rcu/tree_plugin.h:685
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 2d 97 96 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc90000007720 EFLAGS: 00000206
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 __ip_queue_xmit+0x10b1/0x19b0 net/ipv4/ip_output.c:533
 __tcp_transmit_skb+0x1c6c/0x3160 net/ipv4/tcp_output.c:1405
 tcp_delack_timer_handler+0x2a9/0x440 net/ipv4/tcp_timer.c:322
 tcp_delack_timer+0x188/0x2e0 net/ipv4/tcp_timer.c:345
 call_timer_fn+0x1a0/0x670 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1549 [inline]
 __run_timers+0x525/0x7c0 kernel/time/timer.c:1820
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1833
 handle_softirqs+0x2a1/0x920 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194
Code: 74 05 e8 fe d1 65 f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 66 5b 36 f7 65 8b 05 67 14 e1 75 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc90005a17d00 EFLAGS: 00000206
RAX: ee6d1c15b8aa6900 RBX: 0000000000000a06 RCX: ee6d1c15b8aa6900
RDX: dffffc0000000000 RSI: ffffffff8a8c0500 RDI: 0000000000000001
RBP: ffffc90005a17d90 R08: dffffc0000000000 R09: fffffbfff215c46c
R10: fffffbfff215c46c R11: 1ffffffff215c46b R12: dffffc0000000000
R13: 0000000000000000 R14: ffff888073d9c008 R15: 1ffff92000b42fa0
 __do_sys_perf_event_open kernel/events/core.c:12785 [inline]
 __se_sys_perf_event_open+0x124f/0x1e60 kernel/events/core.c:12378
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f96e618eba9
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:00007f96e6f81038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f96e63d5fa0 RCX: 00007f96e618eba9
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000480
RBP: 00007f96e6211e19 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f96e63d6038 R14: 00007f96e63d5fa0 R15: 00007ffd9f68f3c8
 </TASK>