rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12832/1:b..l (detected by 1, t=10503 jiffies, g=86317, q=399 ncpus=2) task:syz-executor state:R running task stack:21504 pid:12832 ppid:12815 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6730 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6754 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 vprintk_emit+0x5c9/0x680 kernel/printk/printk.c:2304 _printk+0xcc/0x110 kernel/printk/printk.c:2328 batadv_check_known_mac_addr+0x29b/0x3e0 net/batman-adv/hard-interface.c:525 batadv_hard_if_event+0x491/0x1550 net/batman-adv/hard-interface.c:992 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455 call_netdevice_notifiers_extack net/core/dev.c:2039 [inline] call_netdevice_notifiers net/core/dev.c:2053 [inline] dev_set_mac_address+0x2c4/0x3d0 net/core/dev.c:8898 dev_set_mac_address_user+0x2d/0x50 net/core/dev.c:8912 do_setlink+0x816/0x3c40 net/core/rtnetlink.c:2788 __rtnl_newlink net/core/rtnetlink.c:3608 [inline] rtnl_newlink+0x17d6/0x1ff0 net/core/rtnetlink.c:3655 rtnetlink_rcv_msg+0x79b/0xed0 net/core/rtnetlink.c:6153 netlink_rcv_skb+0x1de/0x420 net/netlink/af_netlink.c:2511 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x89e/0xbc0 net/netlink/af_netlink.c:1872 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] __sys_sendto+0x44f/0x5c0 net/socket.c:2153 __do_sys_sendto net/socket.c:2165 [inline] __se_sys_sendto net/socket.c:2161 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2161 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7ff01d590a7c RSP: 002b:00007ffcf42edfe0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007ff01e2f4620 RCX: 00007ff01d590a7c RDX: 000000000000002c RSI: 00007ff01e2f4670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffcf42ee034 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007ff01e2f4670 R15: 0000000000000000 rcu: rcu_preempt kthread timer wakeup didn't happen for 10507 jiffies! g86317 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=73107 rcu: rcu_preempt kthread starved for 10510 jiffies! g86317 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26496 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: 13153 Comm: syz.6.1866 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:ksoftirqd_running kernel/softirq.c:95 [inline] RIP: 0010:invoke_softirq kernel/softirq.c:460 [inline] RIP: 0010:__irq_exit_rcu+0x10c/0x220 kernel/softirq.c:679 Code: 08 65 48 8b 3d 4d f7 b3 7e 41 f6 c6 41 0f 95 c0 48 85 ff 0f 94 c1 08 c1 75 27 4c 8d 77 18 4c 89 f0 48 c1 e8 03 42 0f b6 04 20 <84> c0 0f 85 9e 00 00 00 41 83 3e 00 75 09 e8 51 dc 06 00 84 c0 74 RSP: 0018:ffffc90000007f40 EFLAGS: 00000802 RAX: 0000000000000000 RBX: ffff88802c7c8000 RCX: 98449dc1f7b28500 RDX: 1ffffffff1f3ee00 RSI: ffffffff8a8af960 RDI: ffff88813fecbb80 RBP: ffffc90000007fe0 R08: ffffffff8f9f7008 R09: ffffffff8f9f7018 R10: ffffffff8f9f7010 R11: ffffffff8f9f7003 R12: dffffc0000000000 R13: 0000000000000000 R14: ffff88813fecbb98 R15: 1ffff92000000fe8 FS: 00007f16bc7f66c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c336ff5 CR3: 000000002e650000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: irq_exit_rcu+0x5/0x20 kernel/softirq.c:691 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x9d/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 7f c1 f7 02 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc9000461fcb0 EFLAGS: 00000246 RAX: 00000000000000f6 RBX: ffffffff8c5e3b88 RCX: 000000000000083f RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff520008c3f85 R10: fffff520008c3f85 R11: 1ffff920008c3f84 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:603 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline] bpf_trace_run2+0x1cd/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: 0033:0x7f16be52adb9 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:00007f16bc7f5a80 EFLAGS: 00000246 ORIG_RAX: 000000000000000f RAX: ffffffffffffffda RBX: 00007f16be7c5fa0 RCX: 00007f16be52adb9 RDX: 00007f16bc7f5a80 RSI: 00007f16bc7f5bb0 RDI: 0000000000000011 RBP: 00007f16be611e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f16be7c6038 R14: 00007f16be7c5fa0 R15: 00007fff575aec48