Re: [PATCH net-next] net: neighbour: Avoid sending RTM_NEWNEIGH for a dead neighbor

[Petr Machata <petrm@nvidia.com>]

Kuniyuki Iwashima <kuniyu@google.com> writes:

> On Wed, 04 Nov 2026 14:56:56 +0100, Petr Machata wrote:
>
>> --- a/net/core/neighbour.c
>> +++ b/net/core/neighbour.c
>> @@ -3593,6 +3593,13 @@ static void __neigh_notify(struct neighbour *n, int type, int flags,
>>  	int err = -ENOBUFS;
>>  	struct net *net;
>>  
>> +	/* An attempt to send anything but RTM_DELNEIGH on a dead neighbor
>> +	 * indicates that the neighbor was marked dead while another update
>> +	 * gave the lock up for a bit. Do not send such notifications.
>> +	 */
>
> I'd remove the comment, it's apparent from ->dead that there
> was a race and the rest is just repeating the condition bleow.

I figured it might be useful to clarify how it can come up, but yeah.
I'll respin without the comment.

> Otherwise looks good.
>
> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>

Thanks!