Subject: Re: [PATCH v2 0/2] report stop sched scan when actually done
From: Johannes Berg <johannes@sipsolutions.net>
To: Eyal Shapira <eyal@wizery.com>
Cc: linux-wireless@vger.kernel.org, Luciano Coelho <coelho@ti.com>
In-Reply-To: <1324462262-10277-1-git-send-email-eyal@wizery.com> (sfid-20111221_111141_897967_3E904A2C)
References: <1324462262-10277-1-git-send-email-eyal@wizery.com>
	 (sfid-20111221_111141_897967_3E904A2C)
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Date: Wed, 21 Dec 2011 16:10:44 +0100
Message-ID: <1324480244.3401.6.camel@jlt3.sipsolutions.net> (sfid-20111221_161052_039864_FE40B7C5)
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Sender: linux-wireless-owner@vger.kernel.org

On Wed, 2011-12-21 at 12:11 +0200, Eyal Shapira wrote:
> Changes in mac/cfg80211 to notify userspace
> of NL80211_CMD_SCHED_SCAN_STOPPED only when the driver
> actually reported back that it was stopped. Also
> blocks other attempts until we're really done.
> 
> This fixes a scenario where stop sched scan
> is issued and immediately afterwards a new sched scan
> is requested (e.g. with other parameters).
> Current state caused a race where the driver started
> stopping the sched scan but didn't finish and got
> another sched scan request which it couldn't handle.

Luca really needs to take a close look at this, and I think you should
also take a look to see if this kind of API change can be avoided.

johannes