rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=bddc/1/0x4000000000000000 softirq=153778/153783 fqs=3 (detected by 0, t=10502 jiffies, g=214453, q=101 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 88 Comm: kworker/u4:4 Not tainted 5.19.0-syzkaller-13930-g7ebfc85e2cd7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Workqueue: bat_events batadv_purge_orig RIP: 0010:__lock_acquire+0x1ae/0x1f60 kernel/locking/lockdep.c:4963 Code: 0f 84 24 01 00 00 83 fd 31 0f 83 5e 1b 00 00 48 8d 44 ad 00 48 8b 0c 24 48 8d ac c1 70 0a 00 00 48 89 eb 48 c1 eb 03 8a 04 13 <84> c0 0f 85 7f 16 00 00 44 8b 65 00 44 89 e0 25 ff 1f 00 00 44 39 RSP: 0018:ffffc900001e09c8 EFLAGS: 00000802 RAX: 0000000000000000 RBX: 1ffff110031bcc6d RCX: ffff888018de5880 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff91aacd98 RBP: ffff888018de6368 R08: 0000000000000001 R09: 0000000000000001 R10: fffffbfff1c4ace6 R11: 1ffffffff1c4ace5 R12: 0000000000000001 R13: ffffffff91aacd98 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555556831708 CR3: 0000000033197000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000003b DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1a7/0x400 kernel/locking/lockdep.c:5666 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 debug_object_activate+0x97/0x6a0 lib/debugobjects.c:658 debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline] debug_activate kernel/time/hrtimer.c:475 [inline] enqueue_hrtimer kernel/time/hrtimer.c:1084 [inline] __run_hrtimer kernel/time/hrtimer.c:1702 [inline] __hrtimer_run_queues+0x595/0xa60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3a6/0xfd0 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0xf9/0x280 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 RIP: 0010:should_resched arch/x86/include/asm/preempt.h:103 [inline] RIP: 0010:__local_bh_enable_ip+0x16b/0x1f0 kernel/softirq.c:403 Code: 8a e8 e9 59 e5 08 65 66 8b 05 01 a1 b0 7e 66 85 c0 75 57 bf 01 00 00 00 e8 92 7e 0a 00 e8 9d 62 3d 00 fb 65 8b 05 2d 7e af 7e <85> c0 75 05 e8 4c 9b ad ff 48 c7 44 24 20 0e 36 e0 45 49 c7 04 1c RSP: 0018:ffffc90001cdfa00 EFLAGS: 00000286 RAX: 0000000080000000 RBX: 1ffff9200039bf44 RCX: ffffffff8169af8a RDX: dffffc0000000000 RSI: ffffffff8aad75c0 RDI: ffffffff8b0a5460 RBP: ffffc90001cdfab0 R08: dffffc0000000000 R09: fffffbfff1ff3826 R10: fffffbfff1ff3826 R11: 1ffffffff1ff3825 R12: dffffc0000000000 R13: 1ffff9200039bf48 R14: ffffc90001cdfa40 R15: 0000000000000201 spin_unlock_bh include/linux/spinlock.h:394 [inline] batadv_purge_orig_ref+0x15f2/0x16e0 net/batman-adv/originator.c:1259 batadv_purge_orig+0x15/0x60 net/batman-adv/originator.c:1272 process_one_work+0x81c/0xd10 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 rcu: rcu_preempt kthread starved for 10496 jiffies! g214453 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:26424 pid: 16 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5182 [inline] __schedule+0x957/0xe20 kernel/sched/core.c:6494 schedule+0xcb/0x190 kernel/sched/core.c:6570 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1935 rcu_gp_fqs_loop+0x309/0x1070 kernel/rcu/tree.c:1657 rcu_gp_kthread+0xa5/0x390 kernel/rcu/tree.c:1854 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 0 CPU: 0 PID: 6699 Comm: kworker/0:12 Not tainted 5.19.0-syzkaller-13930-g7ebfc85e2cd7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Workqueue: events bpf_map_free_deferred Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x47c/0x4b0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x169/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_check_gp_kthread_starvation+0x1da/0x250 kernel/rcu/tree_stall.h:514 print_other_cpu_stall+0x1554/0x1690 kernel/rcu/tree_stall.h:619 check_cpu_stall kernel/rcu/tree_stall.h:762 [inline] rcu_pending kernel/rcu/tree.c:3660 [inline] rcu_sched_clock_irq+0xa17/0x1950 kernel/rcu/tree.c:2342 update_process_times+0x148/0x1b0 kernel/time/timer.c:1839 tick_sched_handle kernel/time/tick-sched.c:243 [inline] tick_sched_timer+0x377/0x540 kernel/time/tick-sched.c:1480 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4cb/0xa60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3a6/0xfd0 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0xf9/0x280 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 RIP: 0010:csd_lock_wait kernel/smp.c:414 [inline] RIP: 0010:smp_call_function_single+0x402/0x760 kernel/smp.c:777 Code: 04 2b 84 c0 0f 85 4c 01 00 00 45 8b 26 44 89 e6 83 e6 01 31 ff e8 be 19 0b 00 41 83 e4 01 75 08 e8 93 15 0b 00 eb 3f 90 f3 90 <42> 0f b6 04 2b 84 c0 75 10 41 f7 06 01 00 00 00 74 25 e8 77 15 0b RSP: 0018:ffffc90014f079c0 EFLAGS: 00000293 RAX: ffffffff817e7d59 RBX: 1ffff920029e0f41 RCX: ffff888023270000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90014f07b08 R08: ffffffff817e7d32 R09: fffffbfff1ff381c R10: fffffbfff1ff381c R11: 1ffffffff1ff381b R12: 0000000000000001 R13: dffffc0000000000 R14: ffffc90014f07a08 R15: 0000000000000000 rcu_barrier+0x39a/0x670 kernel/rcu/tree.c:3840 htab_map_free+0x25/0xb90 kernel/bpf/hashtab.c:1481 process_one_work+0x81c/0xd10 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 vkms_vblank_simulate: vblank timer overrun