rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P22677/1:b..l rcu: (detected by 0, t=10502 jiffies, g=155737, q=1106 ncpus=2) task:syz-executor state:R running task stack:20544 pid:22677 tgid:22677 ppid:22655 task_flags:0x400140 flags:0x00004002 Call Trace: <TASK> context_switch kernel/sched/core.c:5378 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6765 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6944 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6968 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 vprintk_emit+0x84c/0xa10 kernel/printk/printk.c:2433 _printk+0xd5/0x120 kernel/printk/printk.c:2457 batadv_check_known_mac_addr+0x2bd/0x410 net/batman-adv/hard-interface.c:528 batadv_hard_if_event+0x3a5/0x1810 net/batman-adv/hard-interface.c:998 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2244 [inline] call_netdevice_notifiers net/core/dev.c:2258 [inline] dev_set_mac_address+0x3d9/0x510 net/core/dev.c:9520 dev_set_mac_address_user+0x31/0x50 net/core/dev.c:9534 do_setlink+0x784/0x4300 net/core/rtnetlink.c:3073 rtnl_changelink net/core/rtnetlink.c:3733 [inline] __rtnl_newlink net/core/rtnetlink.c:3885 [inline] rtnl_newlink+0x1704/0x1d30 net/core/rtnetlink.c:4022 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6912 netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2533 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1338 netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1882 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:733 __sys_sendto+0x363/0x4c0 net/socket.c:2187 __do_sys_sendto net/socket.c:2194 [inline] __se_sys_sendto net/socket.c:2190 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2190 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4d8618effc RSP: 002b:00007f4d864cf630 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f4d86ed4620 RCX: 00007f4d8618effc RDX: 000000000000002c RSI: 00007f4d86ed4670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007f4d864cf684 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f4d86ed4670 R15: 0000000000000000 </TASK> rcu: rcu_preempt kthread starved for 7940 jiffies! g155737 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:25752 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: <TASK> context_switch kernel/sched/core.c:5378 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6857 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2024 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2226 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.14.0-rc6-syzkaller-00205-g3571e8b091f4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:211 [inline] RIP: 0010:unwind_next_frame+0x19c/0x22d0 arch/x86/kernel/unwind_orc.c:494 Code: f8 00 00 00 48 c7 c0 00 00 00 81 4d 89 fe 49 29 c6 49 c1 ee 08 48 c7 c0 68 c6 6d 91 48 c7 c1 48 f9 99 91 48 29 c1 48 c1 e9 02 <31> d2 80 3d f3 f9 e7 0c 00 0f 45 d1 8d 42 ff 44 39 f0 0f 86 55 18 RSP: 0018:ffffc90000a279b0 EFLAGS: 00000206 RAX: ffffffff916dc668 RBX: ffffc90000a27ac8 RCX: 00000000000b0cb8 RDX: dffffc0000000000 RSI: ffffffff81ad6b38 RDI: 0000000000000001 RBP: ffffc90000a27ab5 R08: 0000000000000000 R09: ffffc90000a27b70 R10: ffffc90000a27ad0 R11: ffffffff81ad6c00 R12: dffffc0000000000 R13: ffffc90000a27a80 R14: 000000000000ad6b R15: ffffffff81ad6b37 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa984e0df1f CR3: 00000000798aa000 CR4: 00000000003526f0 DR0: 000000000000000e DR1: 000000000000000c DR2: 000000000000000e DR3: 00000000000000b4 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <NMI> </NMI> <IRQ> arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4115 [inline] slab_alloc_node mm/slub.c:4164 [inline] kmem_cache_alloc_node_noprof+0x1d9/0x380 mm/slub.c:4216 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:596 alloc_skb include/linux/skbuff.h:1331 [inline] synproxy_send_client_synack+0x1b9/0xe20 net/netfilter/nf_synproxy_core.c:460 nft_synproxy_eval_v4+0x3ca/0x610 net/netfilter/nft_synproxy.c:59 nft_synproxy_do_eval+0x362/0xa60 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline] nft_do_chain+0x4ad/0x1da0 net/netfilter/nf_tables_core.c:288 nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x29e/0x450 include/linux/netfilter.h:312 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5896 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:6009 process_backlog+0x662/0x15b0 net/core/dev.c:6357 __napi_poll+0xcb/0x490 net/core/dev.c:7191 napi_poll net/core/dev.c:7260 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7382 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:92 [inline] RIP: 0010:acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:112 Code: 90 90 90 90 90 90 90 90 90 65 48 8b 04 25 80 d6 03 00 48 f7 00 08 00 00 00 75 10 66 90 0f 00 2d a5 93 81 00 f3 0f 1e fa fb f4 <fa> c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 RSP: 0018:ffffc900001b7d08 EFLAGS: 00000246 RAX: ffff88801d6f9e00 RBX: ffff8881442fa864 RCX: 00000000003a45f9 RDX: 0000000000000001 RSI: ffff8881442fa800 RDI: ffff8881442fa864 RBP: 000000000003aab8 R08: ffff8880b873799b R09: 1ffff110170e6f33 R10: dffffc0000000000 R11: ffffffff8c090010 R12: ffff888140bb3000 R13: 0000000000000001 R14: 0000000000000001 R15: ffffffff8f3385a0 acpi_idle_enter+0xe4/0x140 drivers/acpi/processor_idle.c:699 cpuidle_enter_state+0x109/0x470 drivers/cpuidle/cpuidle.c:268 cpuidle_enter+0x5d/0xa0 drivers/cpuidle/cpuidle.c:389 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:230 [inline] do_idle+0x372/0x5c0 kernel/sched/idle.c:325 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:423 start_secondary+0x102/0x110 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x147 </TASK>