rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9/1:b..l P5392/1:b..l (detected by 0, t=10502 jiffies, g=19121, q=100) task:modprobe state:R running task stack:27256 pid: 5392 ppid: 3760 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777 irqentry_exit+0x53/0x80 kernel/entry/common.c:432 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:643 RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627 Code: 2b 00 74 08 4c 89 f7 e8 0c 75 67 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:ffffc900024c76a0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000498ee0 RCX: 1ffff92000498e80 RDX: dffffc0000000000 RSI: ffffffff8a8b3da0 RDI: ffffffff8ad904c0 RBP: ffffc900024c77f0 R08: dffffc0000000000 R09: fffffbfff20e2419 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000498edc R13: dffffc0000000000 R14: ffffc900024c7700 R15: 0000000000000246 rcu_lock_acquire+0x20/0x30 include/linux/rcupdate.h:312 rcu_read_lock include/linux/rcupdate.h:739 [inline] get_obj_cgroup_from_current+0xd3/0x2f0 mm/memcontrol.c:2919 memcg_slab_pre_alloc_hook mm/slab.h:283 [inline] slab_pre_alloc_hook+0x87/0xc0 mm/slab.h:497 slab_alloc_node mm/slub.c:3134 [inline] slab_alloc mm/slub.c:3228 [inline] kmem_cache_alloc+0x3f/0x280 mm/slub.c:3233 kmem_cache_zalloc include/linux/slab.h:711 [inline] __alloc_file+0x26/0x240 fs/file_table.c:101 alloc_empty_file+0x92/0x180 fs/file_table.c:150 path_openat+0xfc/0x2f20 fs/namei.c:3728 do_filp_open+0x21c/0x460 fs/namei.c:3769 do_sys_openat2+0x13b/0x4f0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1280 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f2e7bffca46 RSP: 002b:00007ffe73b99e08 EFLAGS: 00000287 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007ffe73b9a068 RCX: 00007f2e7bffca46 RDX: 0000000000080000 RSI: 00007ffe73b99e80 RDI: 00000000ffffff9c RBP: 00007ffe73b99e70 R08: 0000000000080000 R09: 00007ffe73b99e80 R10: 0000000000000000 R11: 0000000000000287 R12: 00007ffe73b99e80 R13: 0000000000000009 R14: 00007ffe73b9a04f R15: 00000000ffffffff task:kworker/u4:0 state:R running task stack:21496 pid: 9 ppid: 2 flags:0x00004000 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777 irqentry_exit+0x53/0x80 kernel/entry/common.c:432 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:643 RIP: 0010:trace_lock_acquire include/trace/events/lock.h:13 [inline] RIP: 0010:lock_acquire+0xd8/0x4f0 kernel/locking/lockdep.c:5594 Code: 08 0f 83 e2 02 00 00 89 d8 c1 e8 06 48 8d 3c c5 a8 60 e9 8d be 08 00 00 00 e8 04 78 67 00 89 d8 48 0f a3 05 82 b2 86 0c 73 0d 03 6b 08 00 84 c0 0f 84 b9 02 00 00 48 c7 c0 44 94 e9 8d 48 c1 RSP: 0018:ffffc90000ce78e0 EFLAGS: 00000257 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff8162ae1c RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8de960a8 RBP: ffffc90000ce7a40 R08: dffffc0000000000 R09: fffffbfff1bd2c16 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200019cf24 R13: dffffc0000000000 R14: 0000000000000000 R15: dffffc0000000000 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312 rcu_read_lock include/linux/rcupdate.h:739 [inline] batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:755 [inline] batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:826 [inline] batadv_iv_ogm_schedule+0x429/0x1000 net/batman-adv/bat_iv_ogm.c:869 batadv_iv_send_outstanding_bat_ogm_packet+0x6fa/0x800 net/batman-adv/bat_iv_ogm.c:1713 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: rcu_preempt kthread starved for 10556 jiffies! g19121 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:26392 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 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: NMI backtrace for cpu 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.15.167-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline] rcu_pending kernel/rcu/tree.c:3932 [inline] rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619 update_process_times+0x196/0x200 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline] __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 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:132 [inline] RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:109 [inline] RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:562 Code: 82 42 f7 48 83 e3 08 0f 85 0a 01 00 00 4c 8d 74 24 20 e8 c4 fe 48 f7 0f 1f 44 00 00 e8 0a 7e 42 f7 0f 00 2d 73 5c a5 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 8b 48 8c f7 RSP: 0018:ffffffff8c607b80 EFLAGS: 000002d3 RAX: ffffffff8a3ddc66 RBX: 0000000000000000 RCX: ffffffff8c6bd5c0 RDX: 0000000000000000 RSI: ffffffff8a8b2b00 RDI: ffffffff8ad904c0 RBP: ffffffff8c607c10 R08: ffffffff8186db50 R09: fffffbfff18d7ab9 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff18c0f70 R13: ffff88801eca8804 R14: ffffffff8c607ba0 R15: dffffc0000000000 acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:697 cpuidle_enter_state+0x521/0xef0 drivers/cpuidle/cpuidle.c:237 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:351 call_cpuidle kernel/sched/idle.c:158 [inline] cpuidle_idle_call kernel/sched/idle.c:239 [inline] do_idle+0x3e4/0x670 kernel/sched/idle.c:306 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 start_kernel+0x48c/0x540 init/main.c:1140 secondary_startup_64_no_verify+0xb1/0xbb