rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P14171/1:b..l (detected by 1, t=10503 jiffies, g=87541, q=120 ncpus=2) task:kworker/u4:32 state:R running task stack:26112 pid:14171 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:lock_acquire+0x20f/0x490 kernel/locking/lockdep.c:5666 Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 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:ffffc90004effac0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 0000000000000000 RCX: c3c20cfb74557700 RDX: 0000000000000000 RSI: ffffffff8a8c1480 RDI: ffffffff8adefae0 RBP: ffffc90004effbc8 R08: dffffc0000000000 R09: fffffbfff215c249 R10: fffffbfff215c249 R11: 1ffffffff215c248 R12: 0000000000000001 R13: 1ffff920009dff64 R14: 0000000000000246 R15: dffffc0000000000 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xeb/0x600 net/batman-adv/network-coding.c:719 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: rcu_preempt kthread starved for 10520 jiffies! g87541 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:27456 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 15897 Comm: syz.3.2519 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:215 Code: 00 00 00 00 00 90 53 48 89 fb e8 17 00 00 00 48 8b 3d 40 a3 9e 0c 48 89 de 5b e9 57 53 4f 00 00 00 cc cc 00 00 cc 48 8b 04 24 <65> 48 8b 0d 14 9f 81 7e 65 8b 15 15 9f 81 7e 81 e2 00 01 ff 00 74 RSP: 0018:ffffc90000007db8 EFLAGS: 00000086 RAX: ffffffff8150b58b RBX: 0000000000000000 RCX: 0000000000000001 RDX: ffff88807d750000 RSI: 0000000000000001 RDI: 0000000000000011 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffed10054d7771 R10: ffffed10054d7771 R11: 1ffff110054d7770 R12: 0000000000000011 R13: dffffc0000000000 R14: ffff88807d750000 R15: 0000000000000001 FS: 00007f759a60d6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f759a5ebf98 CR3: 000000007a8a9000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_signal_generate+0x2b/0x260 include/trace/events/signal.h:50 __send_signal_locked+0xb38/0xde0 kernel/signal.c:1197 do_send_sig_info kernel/signal.c:1301 [inline] group_send_sig_info+0x1f6/0x250 kernel/signal.c:1449 do_bpf_send_signal+0x7b/0x150 kernel/trace/bpf_trace.c:840 irq_work_single+0xd1/0x230 kernel/irq_work.c:211 irq_work_run_list kernel/irq_work.c:242 [inline] irq_work_run+0x152/0x2e0 kernel/irq_work.c:251 __sysvec_irq_work+0xba/0x350 arch/x86/kernel/irq_work.c:22 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x98/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline] RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:206 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 9f bd f7 02 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc90004e67cb0 EFLAGS: 00000246 RAX: 00000000000000f6 RBX: ffffffff8c5e3b88 RCX: 000000000000083f RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff520009ccf85 R10: fffff520009ccf85 R11: 1ffff920009ccf84 R12: ffff8880b8e33e01 R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000000020 arch_irq_work_raise+0x82/0xd0 arch/x86/kernel/irq_work.c:31 irq_work_queue+0x95/0x140 kernel/irq_work.c:114 bpf_send_signal_common+0x2b2/0x420 kernel/trace/bpf_trace.c:879 ____bpf_send_signal kernel/trace/bpf_trace.c:888 [inline] bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:886 bpf_prog_7ba5217f62dcd359+0x38/0x3c bpf_dispatcher_nop_func include/linux/bpf.h:1001 [inline] __bpf_prog_run include/linux/filter.h:596 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline] bpf_trace_run2+0x30a/0x3b0 kernel/trace/bpf_trace.c:2324 __bpf_trace_sys_enter+0x60/0x70 include/trace/events/syscalls.h:18 trace_sys_enter+0x6b/0x80 include/trace/events/syscalls.h:18 syscall_trace_enter+0xf0/0x150 kernel/entry/common.c:81 do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:77 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f759972ade9 Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25 RSP: 002b:00007f759a60ca80 EFLAGS: 00000246 ORIG_RAX: 000000000000000f RAX: ffffffffffffffda RBX: 00007f75999b5fa0 RCX: 00007f759972ade9 RDX: 00007f759a60ca80 RSI: 00007f759a60cbb0 RDI: 0000000000000011 RBP: 00007f7599811e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f75999b6038 R14: 00007f75999b5fa0 R15: 00007fffe08d28d8