rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=be9/1/0x4000000000000000 softirq=12595/12596 fqs=0 (detected by 1, t=10502 jiffies, g=14161, q=61) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 1212 Comm: kworker/u4:4 Not tainted 5.15.166-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:debug_object_deactivate+0x15/0x380 lib/debugobjects.c:743 Code: c7 e0 15 f2 8c 48 89 de e8 68 1b 1d 00 e9 34 ff ff ff 0f 1f 00 55 41 57 41 56 41 55 41 54 53 48 83 ec 20 80 3d 0b 91 db 09 00 <0f> 85 a3 02 00 00 48 89 fb 48 89 74 24 08 49 be 00 00 00 00 00 fc RSP: 0018:ffffc90000007ce8 EFLAGS: 00000046 RAX: ffffffff816f970c RBX: ffff88807e616340 RCX: ffff8880226dd940 RDX: 0000000000010000 RSI: ffffffff8a8cbc40 RDI: ffff88807e616340 RBP: ffffc90000007eb0 R08: ffffffff816f669c R09: ffff88807e616340 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880b902a200 R13: ffff8880b902a300 R14: ffff88807e616340 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f34f670aa8c CR3: 0000000066ff1000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline] debug_deactivate+0x1b/0x1e0 kernel/time/hrtimer.c:481 __run_hrtimer kernel/time/hrtimer.c:1656 [inline] __hrtimer_run_queues+0x31d/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:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627 Code: 2b 00 74 08 4c 89 f7 e8 bc 73 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:ffffc9000513f9e0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000a27f48 RCX: ffffffff81636652 RDX: dffffc0000000000 RSI: ffffffff8a8b3cc0 RDI: ffffffff8ad90100 RBP: ffffc9000513fb30 R08: dffffc0000000000 R09: fffffbfff20e2235 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000a27f44 R13: dffffc0000000000 R14: ffffc9000513fa40 R15: 0000000000000246 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] batadv_nc_purge_paths+0xe8/0x3b0 net/batman-adv/network-coding.c:446 batadv_nc_worker+0x30b/0x5b0 net/batman-adv/network-coding.c:726 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 10502 jiffies! g14161 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 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:26144 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 1 CPU: 1 PID: 4902 Comm: syz.3.339 Not tainted 5.15.166-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 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:csd_lock_wait kernel/smp.c:440 [inline] RIP: 0010:smp_call_function_many_cond+0xaa5/0xd90 kernel/smp.c:969 Code: e6 01 31 ff e8 7c cc 0b 00 41 83 e7 01 75 07 e8 11 c9 0b 00 eb 41 f3 90 48 b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 <41> f7 45 00 01 00 00 00 74 1e e8 ec c8 0b 00 eb db 44 89 e9 80 e1 RSP: 0018:ffffc90002fc74a0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 1ffff11017208541 RCX: ffff88807cf6d940 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90002fc75e0 R08: ffffffff817490e4 R09: ffffed1017227673 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000 R13: ffff8880b9042a08 R14: ffff8880b913b380 R15: 0000000000000001 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135 __flush_tlb_multi arch/x86/include/asm/paravirt.h:87 [inline] flush_tlb_multi arch/x86/mm/tlb.c:900 [inline] flush_tlb_mm_range+0x2a5/0x4a0 arch/x86/mm/tlb.c:986 tlb_flush arch/x86/include/asm/tlb.h:23 [inline] tlb_flush_mmu_tlbonly+0x1ab/0x410 include/asm-generic/tlb.h:430 tlb_flush_mmu mm/mmu_gather.c:246 [inline] tlb_finish_mmu+0xd2/0x320 mm/mmu_gather.c:338 exit_mmap+0x3cd/0x670 mm/mmap.c:3188 __mmput+0x112/0x3b0 kernel/fork.c:1126 exit_mm+0x688/0x7f0 kernel/exit.c:550 do_exit+0x626/0x2480 kernel/exit.c:861 do_group_exit+0x144/0x310 kernel/exit.c:996 get_signal+0xc66/0x14e0 kernel/signal.c:2897 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f34f654fef9 Code: Unable to access opcode bytes at RIP 0x7f34f654fecf. RSP: 002b:00007f34f49c90e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f34f6708f88 RCX: 00007f34f654fef9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f34f6708f88 RBP: 00007f34f6708f80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f34f6708f8c R13: 0000000000000000 R14: 00007ffe9508bd60 R15: 00007ffe9508be48