rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7085/1:b..l (detected by 0, t=10503 jiffies, g=26021, q=78) task:syz-executor state:R running task stack:20608 pid: 7085 ppid: 7078 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6549 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6574 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 vprintk_emit+0x146/0x150 kernel/printk/printk.c:2275 _printk+0xd1/0x120 kernel/printk/printk.c:2299 batadv_check_known_mac_addr+0x28a/0x3d0 net/batman-adv/hard-interface.c:522 batadv_hard_if_event+0x300/0x17a0 net/batman-adv/hard-interface.c:986 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd0/0x170 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2018 [inline] call_netdevice_notifiers_extack net/core/dev.c:2030 [inline] call_netdevice_notifiers net/core/dev.c:2044 [inline] dev_set_mac_address+0x325/0x470 net/core/dev.c:9074 dev_set_mac_address_user+0x2d/0x50 net/core/dev.c:9088 do_setlink+0x7f0/0x3d80 net/core/rtnetlink.c:2702 __rtnl_newlink net/core/rtnetlink.c:3418 [inline] rtnl_newlink+0x17d6/0x2070 net/core/rtnetlink.c:3540 rtnetlink_rcv_msg+0x993/0xee0 net/core/rtnetlink.c:5618 netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2503 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline] netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1352 netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1920 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x564/0x720 net/socket.c:2058 __do_sys_sendto net/socket.c:2070 [inline] __se_sys_sendto net/socket.c:2066 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2066 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f04a1900d8c RSP: 002b:00007fff5ffaa0f0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f04a25e6620 RCX: 00007f04a1900d8c RDX: 000000000000002c RSI: 00007f04a25e6670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007fff5ffaa144 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f04a25e6670 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10478 jiffies! g26021 f0x0 RCU_GP_DOING_FQS(6) ->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:27064 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777 irqentry_exit+0x53/0x80 kernel/entry/common.c:432 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:643 RIP: 0010:rcu_gp_fqs_loop+0xde8/0x1080 kernel/rcu/tree.c:1994 Code: ff f6 44 24 14 01 74 1a 45 31 ff 80 3d 14 09 26 0b 00 41 0f 95 c7 41 c1 e7 02 c7 44 24 14 00 00 00 00 65 4c 8b 35 f8 35 96 7e <4d> 8d a6 68 04 00 00 4c 89 e3 48 c1 eb 03 48 b8 00 00 00 00 00 fc RSP: 0018:ffffc90000d47ca0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000400 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: ffffffff8a8b2a20 RDI: 0000000000000001 RBP: ffffc90000d47df0 R08: ffffffff8186dac0 R09: fffffbfff1924771 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: ffffc90000d47d60 R14: ffff888017e4bb80 R15: 0000000000000000 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 0 CPU: 0 PID: 7361 Comm: syz.0.857 Not tainted 5.15.166-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 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:1085 [inline] __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202 Code: a1 68 f6 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 3e 1e 25 f7 48 89 df e8 16 72 26 f7 e8 b1 25 49 f7 fb bf 01 00 00 00 f6 b7 19 f7 65 8b 05 d7 ba c4 75 85 c0 74 02 5b c3 e8 a4 d7 c2 RSP: 0018:ffffc90002e37d70 EFLAGS: 00000282 RAX: 85f42bb1f49eb200 RBX: ffff88807eb0d340 RCX: ffffffff96867f03 RDX: dffffc0000000000 RSI: ffffffff8a8b2a20 RDI: 0000000000000001 RBP: ffffc90002e37e50 R08: ffffffff8186dac0 R09: ffffed100fd61a69 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff110043bb896 R13: ffff888021ddbb80 R14: 0000000000000000 R15: 1ffff110043bb895 spin_unlock_irq include/linux/spinlock.h:413 [inline] __set_current_blocked+0x2a5/0x2f0 kernel/signal.c:3085 __do_sys_rt_sigreturn+0x181/0x250 arch/x86/kernel/signal.c:672 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f4a96ff9859 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:00007ffce1cdae40 EFLAGS: 00000206 ORIG_RAX: 000000000000000f RAX: ffffffffffffffda RBX: 00007f4a972172a0 RCX: 00007f4a96ff9859 RDX: 00007ffce1cdae40 RSI: 00007ffce1cdaf70 RDI: 0000000000000021 RBP: 00007f4a97217214 R08: 00007f4a97216f80 R09: 00007ffce1cdb847 R10: 0000000000000008 R11: 0000000000000206 R12: 0000000000000003 R13: 00007f4a97217208 R14: 0000000000000003 R15: 00000000000009a2