rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=7f04/1/0x4000000000000002 softirq=178285/178285 fqs=0
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P23111
	(detected by 0, t=10506 jiffies, g=270453, q=491 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 23111 Comm: syz.2.15962 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
RIP: 0010:trace_irq_disable include/trace/events/preemptirq.h:36 [inline]
RIP: 0010:trace_hardirqs_off_finish+0x128/0x180 kernel/trace/trace_preemptirq.c:67
Code: 25 35 20 78 0d 73 85 65 ff 05 4c bd 79 7e 4c 8b 35 95 0a 64 0d 4d 85 f6 74 27 49 83 c6 08 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 <74> 08 4c 89 f7 e8 4e f0 4a 00 49 8b 3e 48 89 de 31 d2 e8 81 f8 ff
RSP: 0000:ffffc900001e0d28 EFLAGS: 00000046
RAX: 1ffff1100aafb563 RBX: ffffffff8a33f213 RCX: ffffffff8188b1eb
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8f00d228
RBP: 0000000000000000 R08: ffffffff8f00d22f R09: 1ffffffff1e01a45
R10: dffffc0000000000 R11: fffffbfff1e01a46 R12: 0000000000000001
R13: 0000000000000000 R14: ffff8880557dab18 R15: dffffc0000000000
FS:  00007f6b4d5506c0(0000) GS:ffff8880b8d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c348e3d CR3: 0000000053cd6000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 irqentry_enter+0x33/0x50 kernel/entry/common.c:385
 sysvec_irq_work+0xa/0xc0 arch/x86/kernel/irq_work.c:17
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:variable_ffs arch/x86/include/asm/bitops.h:319 [inline]
RIP: 0010:handle_softirqs+0x1b7/0x910 kernel/softirq.c:584
Code: 89 7c 24 2c 0f b7 db 48 c7 c7 80 0f 8b 8a e8 90 be e4 08 65 66 c7 05 46 61 b4 7e 00 00 e8 71 6e 39 00 fb 49 c7 c5 c0 a0 60 8d <89> 5c 24 34 b8 ff ff ff ff 0f bc 44 24 34 41 89 c6 41 ff c6 0f 84
RSP: 0000:ffffc900001e0e20 EFLAGS: 00000282
RAX: 7699816d0b175200 RBX: 0000000000000200 RCX: 7699816d0b175200
RDX: dffffc0000000000 RSI: ffffffff8a8c19a0 RDI: ffffffff8adf7160
RBP: ffffc900001e0f30 R08: ffffffff91934277 R09: 1ffffffff232684e
R10: dffffc0000000000 R11: fffffbfff232684f R12: dffffc0000000000
R13: ffffffff8d60a0c0 R14: ffff888091371e00 R15: 000000000000000a
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x13b/0x230 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:rcu_read_unlock_special+0x0/0x510 kernel/rcu/tree_plugin.h:630
Code: 86 9c 66 00 eb b0 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 94 49 89 fd 4c 89 f7 e8 6c 9c 66 00 4c 89 ef eb 84 0f 1f 80 00 00 00 00 <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec c0 00
RSP: 0000:ffffc900038d7b68 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffff88809137223c RCX: 0000000000080000
RDX: ffffc90011b9c000 RSI: 0000000000031db9 RDI: ffff888091371e00
RBP: ffffc900038d7c70 R08: ffffffff91934277 R09: 1ffffffff232684e
R10: dffffc0000000000 R11: fffffbfff232684f R12: 1ffff1101226e447
R13: dffffc0000000000 R14: ffff888091372240 R15: dffffc0000000000
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 count_memcg_event_mm+0x35c/0x3c0 include/linux/memcontrol.h:1099
 handle_mm_fault+0x13d/0x3d40 mm/memory.c:5270
 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338
 handle_page_fault arch/x86/mm/fault.c:1429 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7f6b4c59e56b
Code: 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 e8 ff ff ff f7 d8 <64> 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 41
RSP: 002b:00007f6b4d550028 EFLAGS: 00010217
RAX: 0000000000000009 RBX: 00007f6b4c825fa0 RCX: ffffffffffffffe8
RDX: 000000000000275a RSI: 0000200000000100 RDI: ffffffffffffffff
RBP: 00007f6b4c6358b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6b4c826038 R14: 00007f6b4c825fa0 R15: 00007ffc28066dd8
 </TASK>
task:syz.2.15962     state:R  running task     stack:25104 pid:23111 ppid:18363  flags:0x0000400c
Call Trace:
 <TASK>
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g270453 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=225475
rcu: rcu_preempt kthread starved for 10506 jiffies! g270453 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:27424 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x303/0x1350 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x99/0x3b0 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 23111 Comm: syz.2.15962 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:208
Code: 2e 0f 1f 84 00 00 00 00 00 90 53 48 89 fb e8 17 00 00 00 48 8b 3d e0 8d 7e 0d 48 89 de 5b e9 a7 91 50 00 00 00 cc cc 00 00 cc <48> 8b 04 24 65 48 8b 0d b4 28 80 7e 65 8b 15 b5 28 80 7e 81 e2 00
RSP: 0000:ffffc900001e0538 EFLAGS: 00000002
RAX: ffffffff81a93079 RBX: 0000000000000008 RCX: 0000000000000100
RDX: ffff888091371e00 RSI: 0000000000000008 RDI: 0000000000000000
RBP: ffffc900001e0608 R08: 000000000000007f R09: 0000000000000000
R10: dffffc0000000000 R11: fffff5200003c0f3 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff8880b8d35518 R15: 1ffff9200003c0ac
FS:  00007f6b4d5506c0(0000) GS:ffff8880b8d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c348e3d CR3: 0000000053cd6000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 perf_callchain_store_context include/linux/perf_event.h:1378 [inline]
 get_perf_callchain+0x1c2/0x490 kernel/events/callchain.c:203
 perf_callchain kernel/events/core.c:7522 [inline]
 perf_prepare_sample+0x399/0x2020 kernel/events/core.c:7555
 __perf_event_output kernel/events/core.c:7740 [inline]
 perf_event_output_forward+0x197/0x2f0 kernel/events/core.c:7760
 __perf_event_overflow+0x457/0x630 kernel/events/core.c:9506
 perf_swevent_overflow kernel/events/core.c:9589 [inline]
 perf_swevent_event+0x315/0x570 kernel/events/core.c:9640
 perf_tp_event+0x36b/0xc10 kernel/events/core.c:10074
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10042
 perf_trace_preemptirq_template+0x268/0x320 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:variable_ffs arch/x86/include/asm/bitops.h:319 [inline]
RIP: 0010:handle_softirqs+0x1b7/0x910 kernel/softirq.c:584
Code: 89 7c 24 2c 0f b7 db 48 c7 c7 80 0f 8b 8a e8 90 be e4 08 65 66 c7 05 46 61 b4 7e 00 00 e8 71 6e 39 00 fb 49 c7 c5 c0 a0 60 8d <89> 5c 24 34 b8 ff ff ff ff 0f bc 44 24 34 41 89 c6 41 ff c6 0f 84
RSP: 0000:ffffc900001e0e20 EFLAGS: 00000282
RAX: 7699816d0b175200 RBX: 0000000000000200 RCX: 7699816d0b175200
RDX: dffffc0000000000 RSI: ffffffff8a8c19a0 RDI: ffffffff8adf7160
RBP: ffffc900001e0f30 R08: ffffffff91934277 R09: 1ffffffff232684e
R10: dffffc0000000000 R11: fffffbfff232684f R12: dffffc0000000000
R13: ffffffff8d60a0c0 R14: ffff888091371e00 R15: 000000000000000a
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x13b/0x230 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:rcu_read_unlock_special+0x0/0x510 kernel/rcu/tree_plugin.h:630
Code: 86 9c 66 00 eb b0 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 94 49 89 fd 4c 89 f7 e8 6c 9c 66 00 4c 89 ef eb 84 0f 1f 80 00 00 00 00 <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec c0 00
RSP: 0000:ffffc900038d7b68 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffff88809137223c RCX: 0000000000080000
RDX: ffffc90011b9c000 RSI: 0000000000031db9 RDI: ffff888091371e00
RBP: ffffc900038d7c70 R08: ffffffff91934277 R09: 1ffffffff232684e
R10: dffffc0000000000 R11: fffffbfff232684f R12: 1ffff1101226e447
R13: dffffc0000000000 R14: ffff888091372240 R15: dffffc0000000000
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 count_memcg_event_mm+0x35c/0x3c0 include/linux/memcontrol.h:1099
 handle_mm_fault+0x13d/0x3d40 mm/memory.c:5270
 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338
 handle_page_fault arch/x86/mm/fault.c:1429 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7f6b4c59e56b
Code: 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 e8 ff ff ff f7 d8 <64> 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 41
RSP: 002b:00007f6b4d550028 EFLAGS: 00010217
RAX: 0000000000000009 RBX: 00007f6b4c825fa0 RCX: ffffffffffffffe8
RDX: 000000000000275a RSI: 0000200000000100 RDI: ffffffffffffffff
RBP: 00007f6b4c6358b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6b4c826038 R14: 00007f6b4c825fa0 R15: 00007ffc28066dd8
 </TASK>