rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 0, t=10502 jiffies, g=11065, q=203 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294957316-4294946813), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10504 jiffies! g11065 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:28112 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x107f/0x4030 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 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 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: 4799 Comm: syz.2.19 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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 ff 50 00 03 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc900001e0e60 EFLAGS: 00000046 RAX: 0000000000018e21 RBX: 0000000000018e21 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 0000000000018e21 RDI: 0000000000000838 RBP: 0000000000000000 R08: ffffffff8e200f6f R09: 1ffffffff1c401ed R10: dffffc0000000000 R11: fffffbfff1c401ee R12: dffffc0000000000 R13: 0000000010005df3 R14: ffffffff8c651b40 R15: dffffc0000000000 FS: 00007f598d1a06c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000000058 CR3: 000000007e4c3000 CR4: 00000000003506e0 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+0x561/0x980 kernel/time/hrtimer.c:1890 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:lock_acquire+0x1/0x4a0 kernel/locking/lockdep.c:5630 Code: 0f 8c 3a fb ff ff 48 c7 c7 28 44 20 8e e8 b7 55 6f 00 e9 29 fb ff ff 66 90 65 8b 05 31 7c 9e 7e a9 00 ff ff 00 0f 95 c0 c3 55 <48> 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec e0 00 00 RSP: 0018:ffffc9000482fc60 EFLAGS: 00000246 RAX: ffffffff81c058c8 RBX: ffff88807b8e5f28 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880799cdb58 RBP: 000000000000000e R08: 0000000000000001 R09: 0000000000000000 R10: dffffc0000000000 R11: fffff52000905fcc R12: dffffc0000000000 R13: 1ffff1100f71cbe5 R14: ffffffff81c058d6 R15: ffff8880799cdb58 __might_fault+0xc2/0x120 mm/memory.c:5850 _copy_from_user+0x27/0x170 lib/usercopy.c:14 copy_from_user include/linux/uaccess.h:161 [inline] restore_sigcontext arch/x86/kernel/signal.c:92 [inline] __ia32_sys_rt_sigreturn+0x21c/0x750 arch/x86/kernel/signal.c:675 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f598c33e1d9 Code: 11 06 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 0c 25 RSP: 002b:00007f598d19fb40 EFLAGS: 00000206 ORIG_RAX: 000000000000000f RAX: ffffffffffffffda RBX: 00007f598c615fa8 RCX: 00007f598c33e1d9 RDX: 00007f598d19fb40 RSI: 00007f598d19fc70 RDI: 0000000000000021 RBP: 00007f598c615fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f598c616038 R14: 00007fff19de1740 R15: 00007fff19de1828 sched: RT throttling activated