rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 1, t=10502 jiffies, g=36309, q=120 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294976434-4294965932), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10502 jiffies! g36309 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:27256 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6558 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870 irqentry_exit+0x53/0x80 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:__kasan_check_read+0x6/0x10 mm/kasan/shadow.c:31 Code: 41 5e 41 5f 5d c3 48 c7 c7 75 ea 90 8c eb 0a 48 c7 c7 ad ea 90 8c 4c 89 fe e8 36 01 a7 08 31 db eb d7 cc cc 89 f6 48 8b 0c 24 <31> d2 e9 d3 ec ff ff 0f 1f 00 89 f6 48 8b 0c 24 ba 01 00 00 00 e9 RSP: 0018:ffffc90000157b90 EFLAGS: 00000257 RAX: 0000000000000001 RBX: 1ffff11027fddb28 RCX: ffffffff8a939aa6 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff88813feed940 RBP: ffffc90000157cb0 R08: dffffc0000000000 R09: ffffed1017307541 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88813feed940 R13: 1ffff9200002af78 R14: ffff88813feeebb8 R15: dffffc0000000000 instrument_atomic_read include/linux/instrumented.h:72 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] test_ti_thread_flag include/linux/thread_info.h:118 [inline] need_resched include/linux/sched.h:2231 [inline] schedule+0xd6/0x180 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:308 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: 3552 Comm: syz-fuzzer Not tainted 6.1.94-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:rcu_note_context_switch+0x6/0xf30 kernel/rcu/tree_plugin.h:313 Code: 05 ef fa 9e 0b 48 29 c8 79 0e 48 83 c0 07 78 08 5b 41 5e e9 3c 79 ff ff f0 83 44 24 fc 00 5b 41 5e c3 66 90 55 48 89 e5 41 57 <41> 56 41 55 41 54 53 48 83 e4 e0 48 81 ec 40 01 00 00 41 89 fd 65 RSP: 0018:ffffc90003bdf808 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 1ffff9200077bf28 RCX: dffffc0000000000 RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffffc90003bdf810 R08: dffffc0000000000 R09: ffffc90003bdf960 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001 R13: 1ffff9200077bf40 R14: ffff8880b9800000 R15: ffffc90003bdf940 FS: 000000c0003f3c90(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0325610f00 CR3: 000000001f2b9000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __schedule+0x32e/0x4550 kernel/sched/core.c:6458 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870 irqentry_exit+0x53/0x80 kernel/entry/common.c:439 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:658 RIP: 0010:preempt_count_add+0x0/0x180 kernel/sched/core.c:5698 Code: 48 8b 0c 24 80 e1 07 80 c1 03 38 c1 7c 97 48 8b 3c 24 e8 d3 b2 83 00 eb 8c e9 f2 fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 66 90 <41> 57 41 56 53 89 fb 48 c7 c0 60 51 c9 91 48 c1 e8 03 49 bf 00 00 RSP: 0018:ffffc90003bdfb50 EFLAGS: 00000202 RAX: 0000000000000001 RBX: 1ffff110050553b8 RCX: ffffffff8a939aa6 RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000001 RBP: ffff8880282a9dc0 R08: dffffc0000000000 R09: ffffed10050553b9 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880282a9dc0 R13: ffffc90003bdfc80 R14: ffff8880282ab038 R15: dffffc0000000000 schedule+0xb8/0x180 kernel/sched/core.c:6633 do_wait+0x797/0xb80 kernel/exit.c:1631 kernel_waitid+0x37f/0x520 kernel/exit.c:1699 __do_sys_waitid kernel/exit.c:1712 [inline] __se_sys_waitid+0xe4/0x3e0 kernel/exit.c:1707 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x40720e Code: 48 83 ec 38 e8 13 00 00 00 48 83 c4 38 5d c3 cc cc cc cc cc cc cc cc cc cc cc cc cc 49 89 f2 48 89 fa 48 89 ce 48 89 df 0f 05 <48> 3d 01 f0 ff ff 76 15 48 f7 d8 48 89 c1 48 c7 c0 ff ff ff ff 48 RSP: 002b:000000c000e1f508 EFLAGS: 00000202 ORIG_RAX: 00000000000000f7 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 000000000040720e RDX: 000000c000e1f618 RSI: 0000000000001bad RDI: 0000000000000001 RBP: 000000c000e1f548 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000001000004 R11: 0000000000000202 R12: 000000c000e1f660 R13: 000000c0005e591c R14: 000000c00061fa00 R15: 0000000000000000