rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4246/1:b..l (detected by 0, t=10502 jiffies, g=43081, q=103 ncpus=2) task:syz-executor state:R running task stack:21208 pid:4246 ppid:4241 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 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:691 RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666 Code: 2b 00 74 08 4c 89 f7 e8 af 81 77 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc900041f75e0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff9200083eec8 RCX: 1ffff9200083ee68 RDX: dffffc0000000000 RSI: ffffffff8b0c1340 RDI: ffffffff8b5e6200 RBP: ffffc900041f7740 R08: dffffc0000000000 R09: fffffbfff224984d R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200083eec4 R13: dffffc0000000000 R14: ffffc900041f7640 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] percpu_ref_get_many include/linux/percpu-refcount.h:202 [inline] percpu_ref_get include/linux/percpu-refcount.h:222 [inline] obj_cgroup_get include/linux/memcontrol.h:784 [inline] memcg_slab_post_alloc_hook mm/slab.h:535 [inline] slab_post_alloc_hook+0x1bb/0x3a0 mm/slab.h:745 slab_alloc_node mm/slub.c:3398 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422 anon_vma_chain_alloc mm/rmap.c:141 [inline] anon_vma_fork+0x1f6/0x580 mm/rmap.c:363 dup_mmap kernel/fork.c:663 [inline] dup_mm kernel/fork.c:1541 [inline] copy_mm+0xc83/0x1990 kernel/fork.c:1590 copy_process+0x19d5/0x4060 kernel/fork.c:2266 kernel_clone+0x222/0x920 kernel/fork.c:2681 __do_sys_clone kernel/fork.c:2822 [inline] __se_sys_clone kernel/fork.c:2806 [inline] __x64_sys_clone+0x231/0x280 kernel/fork.c:2806 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: 0033:0x7f1266976793 RSP: 002b:00007ffcfb2f1ff8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1266976793 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 000055558008d7d0 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000000b8786 R14: 00000000000b81ce R15: 00007ffcfb2f2180 rcu: rcu_preempt kthread starved for 9384 jiffies! g43081 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:27160 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 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 6.1.119-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 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: 6b ce f6 48 83 e3 08 0f 85 0b 01 00 00 4c 8d 74 24 20 e8 24 28 d5 f6 0f 1f 44 00 00 e8 9a 67 ce f6 0f 00 2d e3 5c ac 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 1b f1 25 f7 RSP: 0000:ffffffff8d007b20 EFLAGS: 000002d3 RAX: ffffffff8abc3456 RBX: 0000000000000000 RCX: ffffffff8d0bd800 RDX: 0000000000000000 RSI: ffffffff8b0c01c0 RDI: ffffffff8b5e6200 RBP: ffffffff8d007bb0 R08: ffffffff8abc3438 R09: fffffbfff1a17b01 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff1a00f64 R13: ffff888146ed0004 R14: ffffffff8d007b40 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f68df6cac9b CR3: 000000002fc05000 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