rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 ticks this GP) idle=dd5/0/0x3 softirq=6597/6597 fqs=0 (detected by 1, t=10502 jiffies, g=6025, q=152) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:205 Code: 84 00 00 00 00 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 50 d3 f1 0b 48 89 de 5b e9 57 9e 43 00 00 00 cc cc 00 00 cc 48 8b 04 24 <65> 48 8b 0d a4 a3 8a 7e 65 8b 15 a5 a3 8a 7e 81 e2 00 01 ff 00 74 RSP: 0018:ffffc90000007498 EFLAGS: 00000046 RAX: ffffffff81965b71 RBX: ffffc90000007640 RCX: ffffffff8bebc480 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000007590 R08: dffffc0000000000 R09: ffffc900000075e0 R10: fffff52000000ec3 R11: 1ffff92000000ebc R12: dffffc0000000000 R13: ffffc90000007646 R14: 0000000000000000 R15: ffffc90000007800 FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555576f85ce8 CR3: 00000000746ad000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: perf_prepare_sample+0x1341/0x1cb0 kernel/events/core.c:7756 __perf_event_output kernel/events/core.c:7802 [inline] perf_event_output_forward+0x146/0x280 kernel/events/core.c:7822 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515 perf_swevent_overflow kernel/events/core.c:9591 [inline] perf_swevent_event+0x4ad/0x530 kernel/events/core.c:9629 perf_tp_event+0x32c/0xb50 kernel/events/core.c:10047 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021 perf_trace_preemptirq_template+0x2be/0x380 include/trace/events/preemptirq.h:14 trace_irq_enable include/trace/events/preemptirq.h:40 [inline] trace_hardirqs_on_prepare+0x193/0x1f0 kernel/trace/trace_preemptirq.c:32 irqentry_exit+0x4b/0x70 kernel/entry/common.c:421 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713 RIP: 0010:rcu_read_unlock_special+0x84/0x480 kernel/rcu/tree_plugin.h:674 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 ed 11 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b RSP: 0018:ffffc90000007c60 EFLAGS: 00000206 RAX: 18d719c5d077ee00 RBX: 1ffff92000000f90 RCX: 18d719c5d077ee00 RDX: dffffc0000000000 RSI: ffffffff8a0b1c60 RDI: ffffffff8a59e580 RBP: ffffc90000007d28 R08: dffffc0000000000 R09: ffffed1017207662 R10: ffffed1017207662 R11: 1ffff11017207661 R12: ffffffff8c120c00 R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422 rcu_read_unlock include/linux/rcupdate.h:772 [inline] rebalance_domains+0xa51/0xb80 kernel/sched/fair.c:10660 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:730 Code: bf 48 89 df e8 66 76 09 f8 eb b5 e8 9f af f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 cc 66 90 0f 00 2d 37 06 53 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48 RSP: 0018:ffffffff8be07dc8 EFLAGS: 000002c6 RAX: 18d719c5d077ee00 RBX: ffffffff8bebc480 RCX: 18d719c5d077ee00 RDX: 0000000000000001 RSI: ffffffff8a0b1c60 RDI: ffffffff8a59e580 RBP: ffffffff8be07ef8 R08: dffffc0000000000 R09: ffffed1017207662 R10: ffffed1017207662 R11: 1ffff11017207661 R12: ffffffff8d699d28 R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff17d7890 default_idle_call+0x81/0xc0 kernel/sched/idle.c:112 cpuidle_idle_call kernel/sched/idle.c:194 [inline] do_idle+0x21b/0x5b0 kernel/sched/idle.c:306 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 start_kernel+0x486/0x530 init/main.c:1154 secondary_startup_64_no_verify+0xb1/0xbb INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.085 msecs rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g6025 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=3907 rcu: rcu_preempt kthread starved for 10502 jiffies! g6025 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:26240 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 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: 0 Comm: swapper/0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:check_wait_context kernel/locking/lockdep.c:-1 [inline] RIP: 0010:__lock_acquire+0x996/0x7c60 kernel/locking/lockdep.c:4962 Code: 4c 89 f0 48 c1 e8 03 42 0f b6 04 00 84 c0 0f 85 e9 00 00 00 41 0f b6 06 84 c0 74 0e 41 0f b6 cd 44 0f b6 e8 38 c1 44 0f 42 e9 <48> 8b 84 24 88 00 00 00 42 0f b6 04 00 84 c0 0f 85 e3 00 00 00 48 RSP: 0018:ffffc900000071e0 EFLAGS: 00000046 RAX: 0000000000000002 RBX: 0000000000000000 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8ffbe0c0 RBP: ffffc90000007430 R08: dffffc0000000000 R09: fffffbfff1ff7c19 R10: fffffbfff1ff7c19 R11: 1ffffffff1ff7c18 R12: ffffffff8bebcf90 R13: 0000000000000002 R14: ffffffff8f946ff8 R15: ffffffff8bebcf90 FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555576f85ce8 CR3: 00000000746ad000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313 rcu_read_lock include/linux/rcupdate.h:740 [inline] __perf_event_output kernel/events/core.c:7800 [inline] perf_event_output_forward+0x9e/0x280 kernel/events/core.c:7822 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515 perf_swevent_overflow kernel/events/core.c:9591 [inline] perf_swevent_event+0x4ad/0x530 kernel/events/core.c:9629 perf_tp_event+0x32c/0xb50 kernel/events/core.c:10047 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021 perf_trace_preemptirq_template+0x2be/0x380 include/trace/events/preemptirq.h:14 trace_irq_enable include/trace/events/preemptirq.h:40 [inline] trace_hardirqs_on_prepare+0x193/0x1f0 kernel/trace/trace_preemptirq.c:32 irqentry_exit+0x4b/0x70 kernel/entry/common.c:421 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713 RIP: 0010:rcu_read_unlock_special+0x84/0x480 kernel/rcu/tree_plugin.h:674 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 ed 11 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b RSP: 0018:ffffc90000007c60 EFLAGS: 00000206 RAX: 18d719c5d077ee00 RBX: 1ffff92000000f90 RCX: 18d719c5d077ee00 RDX: dffffc0000000000 RSI: ffffffff8a0b1c60 RDI: ffffffff8a59e580 RBP: ffffc90000007d28 R08: dffffc0000000000 R09: ffffed1017207662 R10: ffffed1017207662 R11: 1ffff11017207661 R12: ffffffff8c120c00 R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422 rcu_read_unlock include/linux/rcupdate.h:772 [inline] rebalance_domains+0xa51/0xb80 kernel/sched/fair.c:10660 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:730 Code: bf 48 89 df e8 66 76 09 f8 eb b5 e8 9f af f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 cc 66 90 0f 00 2d 37 06 53 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48 RSP: 0018:ffffffff8be07dc8 EFLAGS: 000002c6 RAX: 18d719c5d077ee00 RBX: ffffffff8bebc480 RCX: 18d719c5d077ee00 RDX: 0000000000000001 RSI: ffffffff8a0b1c60 RDI: ffffffff8a59e580 RBP: ffffffff8be07ef8 R08: dffffc0000000000 R09: ffffed1017207662 R10: ffffed1017207662 R11: 1ffff11017207661 R12: ffffffff8d699d28 R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff17d7890 default_idle_call+0x81/0xc0 kernel/sched/idle.c:112 cpuidle_idle_call kernel/sched/idle.c:194 [inline] do_idle+0x21b/0x5b0 kernel/sched/idle.c:306 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 start_kernel+0x486/0x530 init/main.c:1154 secondary_startup_64_no_verify+0xb1/0xbb INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.186 msecs