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Subject: Re: [RFCv3 3/3] nl80211: Send large new_wiphy events
To:     Johannes Berg <johannes@sipsolutions.net>,
        linux-wireless@vger.kernel.org
References: <20190906154303.9303-1-denkenz@gmail.com>
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From:   Denis Kenzior <denkenz@gmail.com>
Message-ID: <d97f7b4b-6508-4773-b13d-dab052349f47@gmail.com>
Date:   Wed, 11 Sep 2019 08:23:58 -0500
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Hi Johannes,

On 9/11/19 10:12 AM, Johannes Berg wrote:
> On Wed, 2019-09-11 at 07:20 -0500, Denis Kenzior wrote:
> 
>>> I'm not sure I see how the applications could do buffers that are
>>> "inherently" large enough, there's no practical message size limit, is
>>> there (32-bits for the size).
>>
>> The kernel caps this to 32k right now if I read the code correctly.  But
>> fair point.
> 
> The kernel caps this for dumps only, no? We can allocate here ourselves
> for multicasting a message as large as we like I think.
> 

Right, but it is set for only 8k at the moment.  Anyway, I will take 
care of this.

>>>> +	if (WARN_ON(nl80211_send_wiphy(rdev, cmd, msg, 0, 0, 0, &state) < 0)) {
>>>> +		nlmsg_free(msg);
>>>> +		goto legacy;
>>>> +	}
>>>> +
>>>> +	genlmsg_multicast_netns(&nl80211_fam, wiphy_net(&rdev->wiphy), msg, 0,
>>>> +				NL80211_MCGRP_CONFIG2, GFP_KERNEL);
>>>> +
>>>> +legacy:
>>>
>>> nit: just use "else" instead of the goto?
>>
>> I'm not sure I understand?  We want to send both messages here...
> 
> It's equivalent to:
> 
> -----
> if (WARN_ON(nl80211_send_wiphy(...) < 0)
>     nlmsg_free(msg);
> else
>     genlmsg_multicast_netns(...);
> 
> ... code for legacy ...
> -----
> 
> no?

Ah, now I see what you want.  Sure I will take care of this in v4.

Regards,
-Denis