rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 0, t=10502 jiffies, g=7469, q=51 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294959022-4294948519), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10504 jiffies! g7469 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:26712 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5243 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6560 schedule+0xbf/0x180 kernel/sched/core.c:6636 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905 kthread+0x28d/0x320 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: 4287 Comm: syz-executor346 Not tainted 6.1.131-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:__sanitizer_cov_trace_pc+0x58/0x60 kernel/kcov.c:234 Code: f8 15 00 00 83 fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc 15 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 0f 1f 80 00 00 00 00 4c 8b 04 24 65 48 8b 15 14 c5 77 7e 65 8b RSP: 0018:ffffc90003ec7840 EFLAGS: 00000093 RAX: ffffffff817ce917 RBX: 000000001000771e RCX: ffff88802e0b1dc0 RDX: 0000000000000000 RSI: 0000000000000020 RDI: 0000000000000040 RBP: 0000000000000020 R08: ffffffff817ce908 R09: fffffbfff1d4168e R10: 0000000000000000 R11: dffffc0000000001 R12: 0000003e81d14d30 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8f271d8 FS: 0000555557b5b3c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f09980939a0 CR3: 0000000020341000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: clockevents_program_min_delta+0x187/0x410 kernel/time/clockevents.c:247 hrtimer_start_range_ns+0xada/0xc80 kernel/time/hrtimer.c:1303 posixtimer_rearm+0x1ad/0x3f0 kernel/time/posix-timers.c:328 dequeue_signal+0x245/0x590 kernel/signal.c:704 get_signal+0x5ed/0x17a0 kernel/signal.c:2751 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x6a/0x100 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+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f099807984a Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 b3 7e 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 13 7f 02 00 8b 44 24 RSP: 002b:00007ffce5be1e00 EFLAGS: 00000293 RAX: fffffffffffffff7 RBX: 000000000000000b RCX: 00007f099807984a RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000000a RBP: 0000000000000000 R08: 00007f0998032990 R09: 00007f0998032990 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f09980d105c R13: 00007f09980ca10f R14: 00007ffce5be1e50 R15: 0000000000000000 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.465 msecs