From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomi Valkeinen Subject: Re: [RFC][PATCH] omapfb: Condition mutex acquisition Date: Wed, 30 Sep 2009 11:35:32 +0300 Message-ID: <1254299732.23991.57.camel@tubuntu> References: <1254236004.23991.17.camel@tubuntu> <20090930005310.GI16865@atomide.com> Reply-To: tomi.valkeinen@nokia.com Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.nokia.com ([192.100.122.233]:51346 "EHLO mgw-mx06.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750873AbZI3Ifr (ORCPT ); Wed, 30 Sep 2009 04:35:47 -0400 In-Reply-To: <20090930005310.GI16865@atomide.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: ext Tony Lindgren Cc: "ext Aguirre Rodriguez, Sergio Alberto" , "Deak Imre (Nokia-D/Helsinki)" , "linux-omap@vger.kernel.org" On Wed, 2009-09-30 at 02:53 +0200, ext Tony Lindgren wrote: > * Tomi Valkeinen [090929 07:54]: > > On Tue, 2009-09-29 at 16:34 +0200, ext Aguirre Rodriguez, Sergio Alberto > > wrote: > > > From: Tomi Valkeinen [tomi.valkeinen@nokia.com] > > > Sent: Tuesday, September 29, 2009 9:22 AM > > > > On Tue, 2009-09-29 at 16:14 +0200, ext Aguirre Rodriguez, Sergio Alberto > > > > wrote: > > > > > From: Sergio Aguirre > > > > > > > > > > Acquiring mutex before framebuffer registration doesn't make sense, > > > > > As there's no danger of external access to the memory related fields. > > > > > > > > What problem does this patch solve? It makes the code more complex. > > > > > > > > > > Tomi, > > > > > > Thanks for your time. > > > > > > The problem was that, during platform driver registration, > > > this sequence was executed: > > > > > > -> omapfb_probe > > > -> omapfb_do_probe > > > -> planes_init > > > -> fbinfo_init > > > -> set_fb_fix > > > ... > > > -> register_framebuffer > > > > > > And then, inside that function, an attempt of acquiring a > > > mutex failed, because it wasn't initialized before trying it: > > > > > > mutex_lock(&fbi->mm_lock); > > > > > > It is actually initialized later in omapfb_do_probe in register_framebuffer call. > > > > > > So, how is the best to solve this then? > > > > Oh, I wasn't implying that there's something wrong with the fix, I just > > didn't know what it was fixing =). > > > > Looks like a valid fix to me. > > Tomi & Imre, do you want me to add this to the omap-fixes queue, > or are you planning to send other fixes too? > > If you want me to add it, please reply with your ack. > > I'll added it into omap-fixes-testing branch for now so we can > get the omaps booted. I don't know if Imre wants to handle this (probably not =), but I would rather concentrate on DSS2 patches. I have enough of them already, and my progress in upstreaming them seems to be... slow... =). So if you can take any minor old-omapfb patches to omap-fixes queue, it'd be great. Acked-by: Tomi Valkeinen Tomi