rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=7141, q=12 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10499 (4294967054-4294956555), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10500 jiffies! g7141 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:24280 pid:16 tgid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x17d3/0x4a20 kernel/sched/core.c:6736 __schedule_loop kernel/sched/core.c:6813 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6828 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2572 rcu_gp_fqs_loop+0x2df/0x1370 kernel/rcu/tree.c:1663 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:1862 kthread+0x2f2/0x390 kernel/kthread.c:388 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5120 Comm: syz-executor334 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:debug_spin_lock_before kernel/locking/spinlock_debug.c:86 [inline] RIP: 0010:do_raw_spin_lock+0x74/0x370 kernel/locking/spinlock_debug.c:115 Code: 8a 8d 48 c7 44 24 50 10 fa 72 81 48 8d 74 24 40 48 c1 ee 03 48 b8 f1 f1 f1 f1 04 f3 f3 f3 48 89 f1 48 89 74 24 38 48 89 04 16 <48> 8d 5f 04 48 89 d8 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 f6 01 00 RSP: 0018:ffffc90000007be0 EFLAGS: 00000016 RAX: f3f3f304f1f1f1f1 RBX: 1ffff92000000f9c RCX: 1ffff92000000f84 RDX: dffffc0000000000 RSI: 1ffff92000000f84 RDI: ffff8880b942c8c0 RBP: ffffc90000007cb0 R08: ffffffff92ce550f R09: 1ffffffff259caa1 R10: dffffc0000000000 R11: fffffbfff259caa2 R12: ffff8880b942c8c0 R13: 1ffff92000000f98 R14: ffffc90000007ce0 R15: dffffc0000000000 FS: 0000555579a8b3c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002006b000 CR3: 00000000235d2000 CR4: 0000000000350ef0 Call Trace: __raw_spin_lock_irq include/linux/spinlock_api_smp.h:120 [inline] _raw_spin_lock_irq+0xdf/0x120 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1696 [inline] __hrtimer_run_queues+0x65a/0xd00 kernel/time/hrtimer.c:1756 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1818 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x109/0x3a0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202 Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 0a b4 f2 f5 48 89 df e8 c2 f3 f3 f5 e8 1d 19 1d f6 fb bf 01 00 00 00 52 e0 e5 f5 65 8b 05 a3 c4 84 74 85 c0 74 06 5b e9 71 40 00 00 RSP: 0018:ffffc90004577c70 EFLAGS: 00000282 RAX: 1fc13643fc17fe00 RBX: ffff88802878a500 RCX: ffffffff944dd603 RDX: dffffc0000000000 RSI: ffffffff8baac1e0 RDI: 0000000000000001 RBP: ffffc90004577db0 R08: ffffffff8f873a6f R09: 1ffffffff1f0e74d R10: dffffc0000000000 R11: fffffbfff1f0e74e R12: 1ffff110050f1533 R13: 000000001c000004 R14: 0000000000000021 R15: ffff88802878a998 spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x156e/0x1850 kernel/signal.c:2910 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:105 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0xc9/0x360 kernel/entry/common.c:212 do_syscall_64+0x10a/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7ffa0133f040 Code: 10 b0 06 20 31 c0 bf df 00 00 00 48 c7 04 25 08 b0 06 20 08 00 00 00 48 c7 04 25 18 b0 06 20 09 00 00 00 e8 22 4e 03 00 89 df <83> c3 01 e8 68 3f 03 00 83 fb 1e 75 f1 31 ff e8 ac 7a 00 00 66 2e RSP: 002b:00007ffe190e3720 EFLAGS: 00000217 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007ffa01373e79 RDX: 000000002006b000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00000000000f4240 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000555579a8b370 R13: 0000000000000000 R14: 00007ffe190e3790 R15: 00007ffe190e3780 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.123 msecs sched: RT throttling activated