rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=37773, q=538 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294971614-4294961112), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10502 jiffies! g37773 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:26320 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a50 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6837 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1370 kernel/rcu/tree.c:2031 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2233 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/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: CPU: 1 PID: 8596 Comm: syz-executor.0 Not tainted 6.9.0-rc6-next-20240503-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5282 Code: c9 50 e8 79 d4 0b 00 48 83 c4 08 4c 89 f7 e8 ed 38 00 00 0f 1f 44 00 00 4c 89 f7 e8 80 2b 2e 0a e8 bb c7 36 00 fb 48 8b 5d c0 <48> 8d bb f8 15 00 00 48 89 f8 48 c1 e8 03 49 be 00 00 00 00 00 fc RSP: 0018:ffffc9000533f548 EFLAGS: 00000286 RAX: 7a97eda7df334f00 RBX: ffff88807ecb3c00 RCX: ffffffff947a2603 RDX: dffffc0000000000 RSI: ffffffff8bcab340 RDI: ffffffff8c1fd080 RBP: ffffc9000533f590 R08: ffffffff8fad166f R09: 1ffffffff1f5a2cd R10: dffffc0000000000 R11: fffffbfff1f5a2ce R12: 1ffff110172a7ea7 R13: dffffc0000000000 R14: ffff8880b953e7c0 R15: ffff8880b953f538 FS: 0000555588208480(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb50341af80 CR3: 000000006c00c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: context_switch kernel/sched/core.c:5411 [inline] __schedule+0x17f0/0x4a50 kernel/sched/core.c:6745 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7067 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:preempt_schedule_common+0x18/0xd0 kernel/sched/core.c:6932 Code: 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 57 41 56 53 49 bf 00 00 00 00 00 fc ff df eb 0d 48 f7 03 08 00 00 00 <0f> 84 9c 00 00 00 65 ff 05 53 a5 70 74 65 8b 05 4c a5 70 74 25 ff RSP: 0018:ffffc9000533f940 EFLAGS: 00000202 RAX: 1ffff1100fd96780 RBX: ffff88807ecb3c00 RCX: 1ffff92000a67f04 RDX: dffffc0000000000 RSI: ffffffff8bcab340 RDI: ffff88807ecb51f8 RBP: ffffc9000533f9f8 R08: ffffffff8fad166f R09: 1ffffffff1f5a2cd R10: dffffc0000000000 R11: fffffbfff1f5a2ce R12: 1ffff92000a67f30 R13: ffffc9000533fae8 R14: ffffffff8b932f71 R15: dffffc0000000000 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6948 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 class_preempt_destructor include/linux/preempt.h:480 [inline] try_to_wake_up+0x9a8/0x1470 kernel/sched/core.c:4385 wake_up_process kernel/sched/core.c:4510 [inline] wake_up_q+0xc8/0x120 kernel/sched/core.c:1029 futex_wake+0x523/0x5c0 kernel/futex/waitwake.c:199 do_futex+0x392/0x560 kernel/futex/syscalls.c:107 __do_sys_futex kernel/futex/syscalls.c:179 [inline] __se_sys_futex+0x3f9/0x480 kernel/futex/syscalls.c:160 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb50267dd29 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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:00007ffdafc48e48 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb50267dd29 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fb5027abf88 RBP: 00007fb5027abf80 R08: 0000000000000001 R09: 00000000000000bd R10: 000000000000006e R11: 0000000000000246 R12: 00007ffdafc48f60 R13: 00007fb5027abf8c R14: 00007fb5027abf80 R15: 0000000000000000 sched: RT throttling activated