rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3561/1:b..l P4959/1:b..l
	(detected by 0, t=10503 jiffies, g=13009, q=94)
task:syz-executor    state:R  running task     stack:21360 pid: 4959 ppid:  4957 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6571
 preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6596
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 vprintk_emit+0x149/0x150 kernel/printk/printk.c:2275
 _printk+0xda/0x130 kernel/printk/printk.c:2299
 batadv_check_known_mac_addr+0x272/0x3b0 net/batman-adv/hard-interface.c:522
 batadv_hard_if_event+0x4a0/0x17e0 net/batman-adv/hard-interface.c:986
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391
 call_netdevice_notifiers_extack net/core/dev.c:2074 [inline]
 call_netdevice_notifiers net/core/dev.c:2088 [inline]
 dev_set_mac_address+0x2e8/0x400 net/core/dev.c:9140
 dev_set_mac_address_user+0x2d/0x50 net/core/dev.c:9154
 do_setlink+0x8b0/0x3d60 net/core/rtnetlink.c:2739
 __rtnl_newlink net/core/rtnetlink.c:3455 [inline]
 rtnl_newlink+0x1658/0x1a50 net/core/rtnetlink.c:3577
 rtnetlink_rcv_msg+0x844/0xf30 net/core/rtnetlink.c:5687
 netlink_rcv_skb+0x1f5/0x440 net/netlink/af_netlink.c:2507
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x8ba/0xbe0 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:706 [inline]
 __sock_sendmsg net/socket.c:718 [inline]
 __sys_sendto+0x46d/0x620 net/socket.c:2072
 __do_sys_sendto net/socket.c:2084 [inline]
 __se_sys_sendto net/socket.c:2080 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:2080
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f9ad38f27ce
RSP: 002b:00007fff16a10908 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00005555664b4500 RCX: 00007f9ad38f27ce
RDX: 000000000000002c RSI: 00007f9ad46cb670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fff16a10984 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f9ad46cb670 R15: 0000000000000000
 </TASK>
task:udevd           state:R  running task     stack:25232 pid: 3561 ppid:     1 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6571
 preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6596
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
 _raw_spin_unlock_irqrestore+0x10d/0x120 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:419 [inline]
 __wake_up_common_lock kernel/sched/wait.c:140 [inline]
 __wake_up_sync_key+0x128/0x190 kernel/sched/wait.c:205
 sock_def_readable+0x136/0x250 net/core/sock.c:3101
 __netlink_sendskb net/netlink/af_netlink.c:1264 [inline]
 netlink_sendskb+0x97/0x130 net/netlink/af_netlink.c:1270
 netlink_sendmsg+0x8ba/0xbe0 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:706 [inline]
 __sock_sendmsg net/socket.c:718 [inline]
 ____sys_sendmsg+0x5b7/0x8f0 net/socket.c:2445
 ___sys_sendmsg+0x236/0x2e0 net/socket.c:2499
 __sys_sendmsg net/socket.c:2528 [inline]
 __do_sys_sendmsg net/socket.c:2537 [inline]
 __se_sys_sendmsg+0x1af/0x290 net/socket.c:2535
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fdddd1c5407
RSP: 002b:00007ffe7dbde910 EFLAGS: 00000202 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fdddd0d7880 RCX: 00007fdddd1c5407
RDX: 0000000000000000 RSI: 00007ffe7dbde970 RDI: 0000000000000004
RBP: 0000563fddca2d70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000000b3
R13: 0000563fddc919e0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>