rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 GPs behind) idle=00f/1/0x4000000000000000 softirq=8320/8321 fqs=1 (t=10500 jiffies g=9725 q=577) rcu: rcu_preempt kthread starved for 10498 jiffies! g9725 f0x0 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:26168 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 schedule+0x11b/0x1f0 kernel/sched/core.c:6459 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145 kthread+0x3f6/0x4f0 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4577 Comm: syz.0.73 Not tainted 5.15.180-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:212 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:156 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:263 [inline] RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:208 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 1f 67 fe 02 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc90002f3f8c0 EFLAGS: 00000046 RAX: 000000000000003e RBX: ffffffff8c5d19c8 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 000000000000003e RDI: 0000000000000838 RBP: 0000000000000020 R08: ffffffff81725068 R09: fffffbfff1c154b6 R10: 0000000000000000 R11: dffffc0000000001 R12: 000000000000003e R13: dffffc0000000000 R14: 000000000000003e R15: dffffc0000000000 FS: 00007f21e25af6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000006b000 CR3: 0000000061517000 CR4: 00000000003526e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: apic_write arch/x86/include/asm/apic.h:395 [inline] lapic_next_event+0x5b/0x70 arch/x86/kernel/apic/apic.c:468 clockevents_program_min_delta+0x1ae/0x410 kernel/time/clockevents.c:248 hrtimer_start_range_ns+0xada/0xc80 kernel/time/hrtimer.c:1292 posixtimer_rearm+0x1ad/0x3f0 kernel/time/posix-timers.c:328 dequeue_signal+0x1ed/0x520 kernel/signal.c:696 get_signal+0x52e/0x14e0 kernel/signal.c:2781 arch_do_signal_or_restart+0xbd/0x12b0 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307 do_syscall_64+0x47/0x80 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f21e4747167 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:00007f21e25af0e8 EFLAGS: 00000246 RAX: 00000000000000ca RBX: 00007f21e496efa8 RCX: 00007f21e4747169 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f21e496efa8 RBP: 00007f21e496efa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f21e496efac R13: 0000000000000000 R14: 00007fff601971b0 R15: 00007fff60197298 NMI backtrace for cpu 0 CPU: 0 PID: 4562 Comm: syz.2.72 Not tainted 5.15.180-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_dump_cpu_stacks+0x223/0x390 kernel/rcu/tree_stall.h:349 print_cpu_stall+0x320/0x600 kernel/rcu/tree_stall.h:633 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline] rcu_pending kernel/rcu/tree.c:3932 [inline] rcu_sched_clock_irq+0x8d9/0x1150 kernel/rcu/tree.c:2619 update_process_times+0x196/0x200 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1690 [inline] __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1754 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1816 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x13b/0x4b0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627 Code: 2b 00 74 08 4c 89 f7 e8 1c 9b 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc9000303fb20 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000607f70 RCX: ffffffff81635202 RDX: dffffc0000000000 RSI: ffffffff8aab2b80 RDI: ffffffff8af9e940 RBP: ffffc9000303fc68 R08: dffffc0000000000 R09: fffffbfff213181f R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000607f6c R13: dffffc0000000000 R14: ffffc9000303fb80 R15: 0000000000000246 __might_fault+0xb4/0x110 mm/memory.c:5357 _copy_from_user+0x28/0x170 lib/usercopy.c:14 copy_from_user include/linux/uaccess.h:192 [inline] restore_sigcontext arch/x86/kernel/signal.c:91 [inline] __do_sys_rt_sigreturn+0x24d/0xa70 arch/x86/kernel/signal.c:674 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f3f2a040359 Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 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 04 25 RSP: 002b:00007ffcd0b09fc0 EFLAGS: 00000202 ORIG_RAX: 000000000000000f RAX: ffffffffffffffda RBX: 0000000000019df1 RCX: 00007f3f2a040359 RDX: 00007ffcd0b09fc0 RSI: 00007ffcd0b0a0f0 RDI: 0000000000000021 RBP: 0000000000000032 R08: 0000000000000010 R09: 0000001ad0b0a86f R10: 00007ffcd0b0a670 R11: 0000000000000202 R12: 00007f3f2a2cbfac R13: 00007ffcd0b0a670 R14: 0000000000019e23 R15: 00007ffcd0b0a690