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Date:   Thu, 3 Aug 2023 18:21:07 -0700
From:   Brian Norris <briannorris@chromium.org>
To:     Kevin Lund <kglund@google.com>
Cc:     johannes@sipsolutions.net, linux-wireless@vger.kernel.org
Subject: Re: [PATCH 2/2] wifi: mwifiex: Stop rejecting connection attempts
 while connected
Message-ID: <ZMxSg1SmALzTSyGD@google.com>
References: <20230602225751.164525-1-kglund@google.com>
 <20230602225751.164525-2-kglund@google.com>
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On Fri, Jun 02, 2023 at 04:57:51PM -0600, Kevin Lund wrote:
> Currently, the Marvell WiFi driver rejects any connection attmept while
> we are currently connected. This is poor logic, since there are several
> legitimate use-cases for initiating a connection attempt while
> connected, including re-association and BSS Transitioning. This logic
> means that it's impossible for userspace to request the driver to
> connect to a different BSS on the same ESS without explicitly requesting
> a disconnect first.
> 
> Remove the check from the driver so that we can complete BSS transitions
> on the first attempt.
> 
> Testing on Chrome OS has shown that this change resolves some issues
> with failed BSS transitions.
> 
> Signed-off-by: Kevin Lund <kglund@google.com>
> ---
>  drivers/net/wireless/marvell/mwifiex/cfg80211.c | 6 ------
>  1 file changed, 6 deletions(-)

I've been told this one might need an extra look, but first off, it's
marked Rejected, likely due to feedback on patch 1, so probably needs a
resubmit if it needs consideration:

https://patchwork.kernel.org/project/linux-wireless/patch/20230602225751.164525-2-kglund@google.com/

But, did you attempt any background work on this, to determine why it
exists, or what other mitigations are in place? For example, I see that
sme.c's cfg80211_connect() makes a similar check, but only rejects
things if the SSID is different. So with that understanding, it's a
reasonable guess to say that mwifiex would be OK with just relying on
the existing cfg80211 checks instead.

In other words, I think this patch may be OK, but probably could use a
bit more explanation.

Also, how does "BSS Transitioning" (in your description) fit in here?
IIUC, cfg80211_connect() doesn't support that, as it only allows
reassociation to the same BSSID.
(Or, I might be confused here.)

Brian