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Message-ID: <be1934dad73b1cc654615c1c895a79a8b35ea456.camel@sipsolutions.net>
Subject: Re: [PATCH] mac80211: remove warning message
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Yibo Zhao <yiboz@codeaurora.org>, linux-wireless@vger.kernel.org
Cc:     ath10k@lists.infradead.org, Zhi Chen <zhichen@codeaurora.org>
Date:   Tue, 14 May 2019 10:44:45 +0200
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On Fri, 2019-05-10 at 15:01 +0800, Yibo Zhao wrote:
> In multiple SSID cases, it takes time to prepare every AP interface
> to be ready in initializing phase. If a sta already knows everything it
> needs to join one of the APs and sends authentication to the AP which
> is not fully prepared at this point of time, AP's channel context
> could be NULL. As a result, warning message occurs.

Please share the dump, I don't think this should be happening. I think
this warning did what it was supposed to, uncover a bug; rather than
remove the warning we should fix the bug.

> Even worse, if the AP is under attack via tools such as MDK3 and massive
> authentication requests are received in a very short time, console will
> be hung due to kernel warning messages.

I don't buy this, it's just a WARN_ON_ONCE().

> If this case can be hit during normal functionality, there should be no
> WARN_ON(). Those should be reserved to cases that are not supposed to be
> hit at all or some other more specific cases like indicating obsolete
> interface.

I agree, but right now I'm inclined to think it's a bug elsewhere rather
than normal operation.

johannes