rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10500 ticks this GP) idle=3a04/1/0x4000000000000000 softirq=11972/11972 fqs=0 (t=10501 jiffies g=12429 q=113 ncpus=2) rcu: rcu_preempt kthread starved for 10502 jiffies! g12429 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:27576 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696 RIP: 0010:__mod_timer+0x0/0xd20 kernel/time/timer.c:1014 Code: fe ff ff 0f 1f 80 00 00 00 00 41 56 53 48 89 f3 49 89 fe e8 42 80 10 00 4c 89 f7 48 89 de ba 01 00 00 00 5b 41 5e eb 02 66 90 <55> 41 57 41 56 41 55 41 54 53 48 83 ec 60 89 d5 49 89 f6 49 89 fc RSP: 0018:ffffc90000157bb8 EFLAGS: 00000296 RAX: 5ac8069258d90700 RBX: 00000000ffffcc90 RCX: ffffffff96be9101 RDX: 0000000000000004 RSI: 00000000ffffcc90 RDI: ffffc90000157be0 RBP: ffffc90000157cb0 R08: dffffc0000000000 R09: ffffc90000157c10 R10: fffff5200002af84 R11: 1ffff9200002af82 R12: 1ffff9200002af78 R13: 1ffffffff1901e40 R14: ffffc90000157be0 R15: dffffc0000000000 schedule_timeout+0x157/0x280 kernel/time/timer.c:1964 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 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 4642 Comm: syz.0.65 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp8+0xc/0x80 kernel/kcov.c:320 Code: c0 4c 89 01 48 c7 44 11 08 05 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 90 48 8b 04 24 65 48 8b 0d 04 9b 81 7e <65> 8b 15 05 9b 81 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 RSP: 0018:ffffc90004d8fbc0 EFLAGS: 00000246 RAX: ffffffff8150c886 RBX: 0000000000000004 RCX: ffff88802e1f8000 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000000 RBP: ffffc90004d8fec0 R08: dffffc0000000000 R09: ffffed1005c3f001 R10: ffffed1005c3f001 R11: 1ffff11005c3f000 R12: ffff88802dc2d7c0 R13: 0000000000000000 R14: dffffc0000000000 R15: ffff88802e1f8000 FS: 000055556fd5b500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000004000 CR3: 0000000072cb3000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: get_signal+0x116/0x1350 kernel/signal.c:2650 arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f9b4f38eba9 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:00007ffdb5752908 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007f9b4f5d6090 RCX: 00007f9b4f38eba9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f9b4f5d609c RBP: 00007f9b4f5d6090 R08: 0000000000000002 R09: 0000000000000032 R10: 00007f9b4f5d5fa0 R11: 0000000000000246 R12: 00007f9b4f5d5fa0 R13: 00007f9b4f5d6090 R14: 00000000000010ec R15: 0000000000000004 CPU: 0 PID: 4642 Comm: syz.0.65 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp8+0xc/0x80 kernel/kcov.c:320 Code: c0 4c 89 01 48 c7 44 11 08 05 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 90 48 8b 04 24 65 48 8b 0d 04 9b 81 7e <65> 8b 15 05 9b 81 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 RSP: 0018:ffffc90004d8fbc0 EFLAGS: 00000246 RAX: ffffffff8150c886 RBX: 0000000000000004 RCX: ffff88802e1f8000 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000000 RBP: ffffc90004d8fec0 R08: dffffc0000000000 R09: ffffed1005c3f001 R10: ffffed1005c3f001 R11: 1ffff11005c3f000 R12: ffff88802dc2d7c0 R13: 0000000000000000 R14: dffffc0000000000 R15: ffff88802e1f8000 FS: 000055556fd5b500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000004000 CR3: 0000000072cb3000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: get_signal+0x116/0x1350 kernel/signal.c:2650 arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f9b4f38eba9 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:00007ffdb5752908 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007f9b4f5d6090 RCX: 00007f9b4f38eba9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f9b4f5d609c RBP: 00007f9b4f5d6090 R08: 0000000000000002 R09: 0000000000000032 R10: 00007f9b4f5d5fa0 R11: 0000000000000246 R12: 00007f9b4f5d5fa0 R13: 00007f9b4f5d6090 R14: 00000000000010ec R15: 0000000000000004 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4640 Comm: syz.2.63 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline] RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:206 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 bf c9 f7 02 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc900001e0e38 EFLAGS: 00000046 RAX: 000000000008dafa RBX: 000000000008dafa RCX: 0000000000000838 RDX: 0000000000000000 RSI: 000000000008dafa RDI: 0000000000000838 RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1c3ee4e R10: fffffbfff1c3ee4e R11: 1ffffffff1c3ee4d R12: dffffc0000000000 R13: 0000000010003fc0 R14: ffffffff8c5e3b40 R15: dffffc0000000000 FS: 00007fba79c466c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9b4f371fe0 CR3: 00000000308de000 CR4: 00000000003526e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: apic_write arch/x86/include/asm/apic.h:394 [inline] lapic_next_event+0x5b/0x70 arch/x86/kernel/apic/apic.c:478 clockevents_program_event+0x1bc/0x310 kernel/time/clockevents.c:334 hrtimer_interrupt+0x59d/0x9c0 kernel/time/hrtimer.c:1891 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline] __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202 Code: f5 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 3e 18 42 f7 48 89 df e8 96 dd 42 f7 e8 21 d1 65 f7 fb bf 01 00 00 00 e6 5a 36 f7 65 8b 05 e7 13 e1 75 85 c0 74 02 5b c3 e8 34 25 df RSP: 0018:ffffc90005107bb8 EFLAGS: 00000286 RAX: d53e3d449c2f1f00 RBX: ffff88807829a500 RCX: d53e3d449c2f1f00 RDX: dffffc0000000000 RSI: ffffffff8a8c0300 RDI: 0000000000000001 RBP: ffff88807829a998 R08: dffffc0000000000 R09: ffffed100f0534a1 R10: ffffed100f0534a1 R11: 1ffff1100f0534a0 R12: 1ffff1100f053533 R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000 spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x1163/0x1350 kernel/signal.c:2874 arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fba78d8eba7 Code: ff ff 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 RSP: 002b:00007fba79c460e8 EFLAGS: 00000246 RAX: 00000000000000ca RBX: 00007fba78fd6098 RCX: 00007fba78d8eba9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fba78fd6098 RBP: 00007fba78fd6090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fba78fd6128 R14: 00007ffdb022cde0 R15: 00007ffdb022cec8