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Subject: Re: [PATCH wireless-2.6] iwlwifi: do not perferm force reset while
 doing scan
From: Johannes Berg <johannes@sipsolutions.net>
To: Stanislaw Gruszka <sgruszka@redhat.com>
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Date: Wed, 22 Sep 2010 16:39:57 +0200
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On Wed, 2010-09-22 at 10:57 +0200, Stanislaw Gruszka wrote:

> So why we can see this warning? During my testing I saw it also.
> There is race regarding SCAN_HW_SCANNING bit, usually we set/clear
> this bit under local->mtx, but not in ieee80211_restart_hw()
> 
> cpu0						cpu1
> __ieee80211_start_scan
>   __set_bit(SCAN_HW_SCANNING, &local->scanning);
>   
> 						iwl_bg_restart()
> 						  ieee80211_restart_hw()
> 						    WARN

Why can't iwlwifi's bg_restart() force-abort the scan? It'll be aborted
anyway...

johannes