rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=a81/1/0x4000000000000000 softirq=22795/22796 fqs=2 (detected by 0, t=10505 jiffies, g=35389, q=217) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4275 Comm: kworker/u4:6 Not tainted 5.15.184-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:check_region_inline mm/kasan/generic.c:169 [inline] RIP: 0010:kasan_check_range+0xd/0x290 mm/kasan/generic.c:189 Code: c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 00 00 cc cc 00 00 cc cc 00 00 cc cc b0 01 48 85 f6 0f 84 a4 01 00 00 41 57 <41> 56 53 49 89 f8 49 01 f0 0f 82 57 02 00 00 49 89 f8 49 c1 e8 2f RSP: 0018:ffffc90000dd08d0 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000000015 RCX: ffffffff815bfa8f RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8ff9b0c0 RBP: ffffc90000dd0b30 R08: dffffc0000000000 R09: fffffbfff1ff361a R10: fffffbfff1ff361a R11: 1ffffffff1ff3619 R12: 0000000054b51547 R13: ffff8880263e9dc0 R14: 00000000b38054f9 R15: ffff8880263ea948 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b33615ff8 CR3: 000000002a825000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] hlock_class kernel/locking/lockdep.c:197 [inline] __lock_acquire+0x10af/0x7c60 kernel/locking/lockdep.c:5008 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline] _raw_spin_lock_irq+0x9f/0xe0 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1694 [inline] __hrtimer_run_queues+0x5ff/0xc40 kernel/time/hrtimer.c:1754 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 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:lock_acquire+0x1f2/0x3f0 kernel/locking/lockdep.c:5627 Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f6 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b RSP: 0018:ffffc9000319faa0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 0000000000000000 RCX: d7d3bbba926ca800 RDX: 0000000000000000 RSI: ffffffff8a0b2460 RDI: ffffffff8a59a700 RBP: ffffc9000319fbc0 R08: dffffc0000000000 R09: fffffbfff1ff3619 R10: fffffbfff1ff3619 R11: 1ffffffff1ff3618 R12: ffffffff8c11c060 R13: 1ffff92000633f60 R14: 0000000000000246 R15: dffffc0000000000 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312 rcu_read_lock include/linux/rcupdate.h:739 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline] batadv_nc_worker+0xc9/0x5c0 net/batman-adv/network-coding.c:723 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: rcu_preempt kthread starved for 10495 jiffies! g35389 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:27008 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 schedule+0x11b/0x1e0 kernel/sched/core.c:6459 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145 kthread+0x436/0x520 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: 4230 Comm: kworker/0:6 Not tainted 5.15.184-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events bpf_prog_free_deferred Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487 print_other_cpu_stall+0x10c8/0x1220 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+0x831/0x1110 kernel/rcu/tree.c:2619 update_process_times+0x193/0x200 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1690 [inline] __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 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+0xb88/0xd70 kernel/smp.c:969 Code: b6 44 05 00 84 c0 0f 85 9d 00 00 00 41 8b 1c 24 89 de 83 e6 01 31 ff e8 a6 55 0b 00 83 e3 01 75 07 e8 3c 52 0b 00 eb 43 f3 90 <48> b8 00 00 00 00 00 fc ff df 41 0f b6 44 05 00 84 c0 75 11 41 f7 RSP: 0018:ffffc9000311f840 EFLAGS: 00000293 RAX: ffffffff816c6f2b RBX: 0000000000000001 RCX: ffff888025ba3b80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000311f980 R08: dffffc0000000000 R09: fffffbfff1ff361a R10: fffffbfff1ff361a R11: 1ffffffff1ff3619 R12: ffff8880b9140588 R13: 1ffff110172280b1 R14: ffff8880b903b380 R15: 0000000000000001 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135 __purge_vmap_area_lazy+0x216/0x18f0 mm/vmalloc.c:1683 _vm_unmap_aliases+0x410/0x4a0 mm/vmalloc.c:2107 vm_remove_mappings mm/vmalloc.c:2584 [inline] __vunmap+0x70d/0xa40 mm/vmalloc.c:2611 bpf_jit_binary_free kernel/bpf/core.c:918 [inline] bpf_jit_free+0x92/0x180 kernel/bpf/core.c:931 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287