rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10502 jiffies, g=7773, q=24 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10499 (4294970269-4294959770), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10500 jiffies! g7773 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:27664 pid:16 tgid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6746 __schedule_loop kernel/sched/core.c:6823 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6838 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2582 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:1663 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:1862 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 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: 5122 Comm: syz-executor760 Not tainted 6.9.0-rc4-syzkaller-00329-g48cf398f15fc #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:__update_load_avg_cfs_rq+0x36e/0x940 kernel/sched/pelt.c:333 Code: 00 89 db be 08 00 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 90 30 9f 8f e8 30 f8 81 00 48 0f a3 1d 08 36 38 0e 0f 82 f3 00 00 00 <48> 83 c4 20 b8 01 00 00 00 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc RSP: 0018:ffffc90000a08de0 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff8166fa80 RDX: 0000000000000000 RSI: ffffffff8b6f56a0 RDI: ffffffff8d260b48 RBP: 000000000000ba11 R08: 0000000000000000 R09: fffffbfff1f3e612 R10: ffffffff8f9f3097 R11: 0000000000000001 R12: 000000000003d78c R13: 0000000000000029 R14: ffff8880b953eb88 R15: 0000000000000012 FS: 000055557ed5a3c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002006b000 CR3: 0000000076636000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: update_cfs_rq_load_avg kernel/sched/fair.c:4634 [inline] __update_blocked_fair kernel/sched/fair.c:9325 [inline] update_blocked_averages+0x729/0x2160 kernel/sched/fair.c:9431 run_rebalance_domains+0x123/0x1a0 kernel/sched/fair.c:12427 __do_softirq+0x218/0x922 kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:633 [inline] irq_exit_rcu+0xb9/0x120 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:write_comp_data+0x34/0x90 kernel/kcov.c:236 Code: 48 8b 15 ff 1b 76 7e 65 8b 05 00 1c 76 7e a9 00 01 ff 00 74 0f f6 c4 01 74 59 8b 82 14 16 00 00 85 c0 74 4f 8b 82 f0 15 00 00 <83> f8 03 75 44 48 8b 82 f8 15 00 00 8b 92 f4 15 00 00 48 8b 38 48 RSP: 0018:ffffc9000338fb00 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8133a8dc RDX: ffff88802935bc00 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 00007ffca8b0d5c0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 00007ffca8b0d5c0 R13: 0000000000000000 R14: ffffc9000338fbb0 R15: 0000000000000007 __fpu_restore_sig+0x23c/0x1430 arch/x86/kernel/fpu/signal.c:357 fpu__restore_sig+0x102/0x180 arch/x86/kernel/fpu/signal.c:493 restore_sigcontext+0x4ca/0x6a0 arch/x86/kernel/signal_64.c:95 __do_sys_rt_sigreturn+0x138/0x230 arch/x86/kernel/signal_64.c:263 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6f6dcbce79 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 18 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffca8b0d998 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007f6f6dcbce79 RDX: 000000002006b000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00000000000f4240 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000055557ed5a370 R13: 0000000000000001 R14: 00007ffca8b0da10 R15: 00007ffca8b0da00 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.954 msecs