rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4305/1:b..l (detected by 0, t=10502 jiffies, g=12621, q=168 ncpus=2) task:syz.3.132 state:R running task stack:25528 pid:4305 ppid:4045 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6561 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6873 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:__sanitizer_cov_trace_pc+0x58/0x60 kernel/kcov.c:225 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 54 d4 77 7e 65 8b RSP: 0018:ffffc900032efa58 EFLAGS: 00000246 RAX: ffffffff89087d72 RBX: 0000000000000001 RCX: 0000000000040000 RDX: ffffc90013402000 RSI: 000000000003ffff RDI: 0000000000040000 RBP: ffffc900032efb90 R08: ffffffff89087d60 R09: fffffbfff2093845 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200065df66 R13: dffffc0000000000 R14: ffff88814b472998 R15: 000000000000e533 rcu_read_unlock include/linux/rcupdate.h:820 [inline] inet_twsk_purge+0x922/0xa40 net/ipv4/inet_timewait_sock.c:336 ops_exit_list net/core/net_namespace.c:177 [inline] setup_net+0x939/0xb90 net/core/net_namespace.c:358 copy_net_ns+0x392/0x5d0 net/core/net_namespace.c:481 create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11e/0x170 kernel/nsproxy.c:226 ksys_unshare+0x580/0xb20 kernel/fork.c:3203 __do_sys_unshare kernel/fork.c:3274 [inline] __se_sys_unshare kernel/fork.c:3272 [inline] __x64_sys_unshare+0x34/0x40 kernel/fork.c:3272 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: 0033:0x7f51f5d75f19 RSP: 002b:00007f51f5bff048 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007f51f5f06110 RCX: 00007f51f5d75f19 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006a040000 RBP: 00007f51f5de4e68 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f51f5f06110 R15: 00007ffd09462078 rcu: rcu_preempt kthread starved for 10523 jiffies! g12621 f0x0 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:25816 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6561 schedule+0xbf/0x180 kernel/sched/core.c:6637 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: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.1.100-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:130 [inline] RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:112 [inline] RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:567 Code: 0b f5 f6 48 83 e3 08 0f 85 0b 01 00 00 4c 8d 74 24 20 e8 f4 c9 fb f6 0f 1f 44 00 00 e8 4a 07 f5 f6 0f 00 2d 63 d5 b1 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 3b 8f 4c f7 RSP: 0018:ffffffff8ce07b20 EFLAGS: 000002d3 RAX: ffffffff8a959336 RBX: 0000000000000000 RCX: ffffffff8cebd800 RDX: 0000000000000000 RSI: ffffffff8aec0240 RDI: ffffffff8b3d48a0 RBP: ffffffff8ce07bb0 R08: ffffffff8a959318 R09: fffffbfff19d7b01 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff19c0f64 R13: ffff888014346004 R14: ffffffff8ce07b40 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3f741f6e00 CR3: 00000000224ae000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:704 cpuidle_enter_state+0x516/0xf80 drivers/cpuidle/cpuidle.c:239 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:356 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x3ce/0x680 kernel/sched/idle.c:303 cpu_startup_entry+0x3d/0x60 kernel/sched/idle.c:401 rest_init+0x2da/0x300 init/main.c:733 arch_call_rest_init+0xa/0xa init/main.c:893 start_kernel+0x496/0x53f init/main.c:1140 secondary_startup_64_no_verify+0xcf/0xdb