rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 1, t=10502 jiffies, g=49225, q=9) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294993105-4294982603), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10502 jiffies! g49225 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:26752 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 11092 Comm: syz.1.1506 Not tainted 5.15.180-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:arch_atomic_try_cmpxchg arch/x86/include/asm/atomic.h:-1 [inline] RIP: 0010:atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:513 [inline] RIP: 0010:queued_spin_lock include/asm-generic/qspinlock.h:82 [inline] RIP: 0010:do_raw_spin_lock+0x16a/0x370 kernel/locking/spinlock_debug.c:115 Code: be 04 00 00 00 e8 86 28 66 00 41 0f b6 44 1d 00 84 c0 48 89 da 0f 85 89 01 00 00 8b 44 24 60 b9 01 00 00 00 f0 41 0f b1 0c 24 <0f> 85 db 00 00 00 65 8b 1d 41 09 9e 7e 41 0f b6 04 17 84 c0 0f 85 RSP: 0018:ffffc90000007be0 EFLAGS: 00000046 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffc90000007c40 RBP: ffffc90000007cb0 R08: dffffc0000000000 R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: ffff8880b8e2a200 R13: 1ffff92000000f88 R14: ffffc90000007c40 R15: 1ffff110171c5441 FS: 00007fb23f7306c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000006b000 CR3: 0000000065bb9000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock_irq include/linux/spinlock_api_smp.h:129 [inline] _raw_spin_lock_irq+0xdb/0x110 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1694 [inline] __hrtimer_run_queues+0x662/0xcf0 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:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202 Code: 31 60 f6 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 ae ec 19 f7 48 89 df e8 06 41 1b f7 e8 b1 f0 3d f7 fb bf 01 00 00 00 d6 83 0e f7 65 8b 05 b7 a0 b9 75 85 c0 74 02 5b c3 e8 64 bc b7 RSP: 0018:ffffc900046d7bc0 EFLAGS: 00000282 RAX: ebec05036c671c00 RBX: ffff888073f59280 RCX: ffffffff96a92f03 RDX: dffffc0000000000 RSI: ffffffff8aab18e0 RDI: 0000000000000001 RBP: 0000000000000000 R08: ffffffff8186bfe0 R09: ffffed100e7eb251 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000021 R13: dffffc0000000000 R14: ffff888073f59718 R15: ffff888073f59280 spin_unlock_irq include/linux/spinlock.h:413 [inline] get_signal+0x13ee/0x14e0 kernel/signal.c:2903 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: 0033:0x7fb2418c8167 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:00007fb23f7300e8 EFLAGS: 00000246 RAX: 00000000000000ca RBX: 00007fb241aeffa8 RCX: 00007fb2418c8169 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fb241aeffa8 RBP: 00007fb241aeffa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb241aeffac R13: 0000000000000000 R14: 00007ffdf0cceca0 R15: 00007ffdf0cced88