Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756936AbZGEPBx (ORCPT ); Sun, 5 Jul 2009 11:01:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753995AbZGEPBo (ORCPT ); Sun, 5 Jul 2009 11:01:44 -0400 Received: from 124x34x33x190.ap124.ftth.ucom.ne.jp ([124.34.33.190]:45772 "EHLO master.linux-sh.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752986AbZGEPBn (ORCPT ); Sun, 5 Jul 2009 11:01:43 -0400 Date: Mon, 6 Jul 2009 00:01:35 +0900 From: Paul Mundt To: Linus Torvalds Cc: Wu Zhangjin , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@linux-mips.org, Krzysztof Helt , Peter Zijlstra , "Rafael J. Wysocki" , Andrew Morton , Ralf Baechle , ???? , zhangfx Subject: Re: [BUG] drivers/video/sis: deadlock introduced by "fbdev: add mutex for fb_mmap locking" Message-ID: <20090705150134.GB8326@linux-sh.org> Mail-Followup-To: Paul Mundt , Linus Torvalds , Wu Zhangjin , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@linux-mips.org, Krzysztof Helt , Peter Zijlstra , "Rafael J. Wysocki" , Andrew Morton , Ralf Baechle , ???? , zhangfx References: <1246785112.14240.34.camel@falcon> <20090705145203.GA8326@linux-sh.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 903 Lines: 23 On Sun, Jul 05, 2009 at 07:56:56AM -0700, Linus Torvalds wrote: > > > On Sun, 5 Jul 2009, Paul Mundt wrote: > > break; > > fb_info->node = i; > > mutex_init(&fb_info->lock); > > - mutex_init(&fb_info->mm_lock); > > Why not "lock" as well? > I had that initially, but matroxfb will break if we do that, and presently nothing cares about trying to take ->lock that early on. ->mm_lock was a special case as the lock/unlock pairs were sprinkled around well before initialization, while in the ->lock case all of the lock/unlock pairs are handled internally by the fbmem code (at least a quick grep does not show any drivers using it on their own). -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/