rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=b2d/1/0x4000000000000000 softirq=9226/9227 fqs=4 (detected by 1, t=10502 jiffies, g=10917, q=73) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4359 Comm: kworker/u4:6 Not tainted 5.15.170-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:lookup_object_or_alloc lib/debugobjects.c:568 [inline] RIP: 0010:debug_object_activate+0x68/0x4e0 lib/debugobjects.c:696 Code: 48 0f af c8 48 c1 e9 2f 83 e1 f8 4c 8d a4 c9 00 30 a1 96 48 8d bc c9 08 30 a1 96 48 89 7c 24 10 e8 8d d5 2f 06 48 89 44 24 08 <4c> 89 e0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 e7 e8 62 60 bc fd RSP: 0018:ffffc90000007cc8 EFLAGS: 00000046 RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffc90000007ba0 RBP: ffffffff8a8cbca0 R08: dffffc0000000000 R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: ffffffff96a36088 R13: ffff888076dc8b40 R14: ffff888076dc8b40 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020003c80 CR3: 000000001f772000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline] debug_activate kernel/time/hrtimer.c:475 [inline] enqueue_hrtimer+0x30/0x390 kernel/time/hrtimer.c:1084 __run_hrtimer kernel/time/hrtimer.c:1705 [inline] __hrtimer_run_queues+0x6b6/0xcf0 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x13b/0x4b0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:should_resched arch/x86/include/asm/preempt.h:103 [inline] RIP: 0010:__local_bh_enable_ip+0x16c/0x1f0 kernel/softirq.c:390 Code: 8a e8 28 a9 e6 08 65 66 8b 05 30 0e b6 7e 66 85 c0 75 57 bf 01 00 00 00 e8 11 f2 09 00 e8 6c 67 39 00 fb 65 8b 05 1c e5 b4 7e <85> c0 75 05 e8 eb 01 b3 ff 48 c7 44 24 20 0e 36 e0 45 49 c7 04 1c RSP: 0018:ffffc900014efaa0 EFLAGS: 00000286 RAX: 0000000080000000 RBX: 1ffff9200029df58 RCX: ffffffff81632d78 RDX: dffffc0000000000 RSI: ffffffff8a8b2a80 RDI: ffffffff8ad90480 RBP: ffffc900014efb50 R08: dffffc0000000000 R09: fffffbfff20ec63e R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff9200029df5c R14: ffffc900014efae0 R15: 0000000000000201 spin_unlock_bh include/linux/spinlock.h:408 [inline] batadv_nc_purge_paths+0x30e/0x3b0 net/batman-adv/network-coding.c:475 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 10494 jiffies! g10917 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:26816 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: 5062 Comm: syz.3.308 Not tainted 5.15.170-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:1097 [inline] __sysvec_apic_timer_interrupt+0x13b/0x4b0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline] RIP: 0010:smp_call_function_many_cond+0xa93/0xd90 kernel/smp.c:969 Code: 04 03 84 c0 0f 85 84 00 00 00 45 8b 7d 00 44 89 fe 83 e6 01 31 ff e8 5c d5 0b 00 41 83 e7 01 75 07 e8 f1 d1 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 RSP: 0018:ffffc900035974a0 EFLAGS: 00000293 RAX: ffffffff8174a1f4 RBX: 1ffff11017208541 RCX: ffff88805b8d0000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900035975e0 R08: ffffffff8174a1c4 R09: ffffed1017207679 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:2900 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: 0033:0x7fae53fd0719 Code: Unable to access opcode bytes at RIP 0x7fae53fd06ef. RSP: 002b:00007fae524480e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007fae54187f88 RCX: 00007fae53fd0719 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fae54187f88 RBP: 00007fae54187f80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fae54187f8c R13: 0000000000000000 R14: 00007ffff28f8660 R15: 00007ffff28f8748