Delivered-To: jwboyer@gmail.com Received: by 10.101.212.35 with SMTP id o35csp6769anq; Sat, 2 Mar 2013 05:50:51 -0800 (PST) X-Received: by 10.68.137.42 with SMTP id qf10mr19122124pbb.80.1362232251119; Sat, 02 Mar 2013 05:50:51 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id pu7si8560937pbc.232.2013.03.02.05.50.50; Sat, 02 Mar 2013 05:50:51 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mail=linux-kernel-owner@vger.kernel.org; dkim=neutral (body hash did not verify) header.i=@gmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752198Ab3CBNuU (ORCPT + 99 others); Sat, 2 Mar 2013 08:50:20 -0500 Received: from mail-ee0-f48.google.com ([74.125.83.48]:46431 "EHLO mail-ee0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752038Ab3CBNuT (ORCPT ); Sat, 2 Mar 2013 08:50:19 -0500 Received: by mail-ee0-f48.google.com with SMTP id t10so2921534eei.7 for ; Sat, 02 Mar 2013 05:50:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-received:date:from:to:cc:subject:message-id:references :mime-version:content-type:content-disposition:in-reply-to :user-agent; bh=8ABPYEMGQsyhtGtpdGpnD1kQchBrqYm9rJ3sEUcIQOc=; b=hx/4GjbvaME9C3c+WOrfUkkwnJ5jJXefsOhCKmPCE8kmswk3Tvm11198r4+y1jM/Bl 1wtIYby6sFgA08JUldm09fPpsKfbdeDnFAI5WmUAGJjahFXXRrQPocI6E0+s2BcM+t3H Ii8g8ZvYJ+YMgbbSmp7mwMv98aa0+qdY6TIF4P/wNwAWrsjFh5TBgc/QyB0MzyQQ2tMp LfA7n/2sH11vofS6FLSaWhtwGIIexPZ+oxWpvwBcCIYX+gTrSHPZqnLQkvhQ5oZDx7WF 6QlNEqlmL+usW1ApRCAwcL4jOaORDAC2MytGH4jdZNic0PqdzonfbJTRE6YmZ45FHtNG l+6w== X-Received: by 10.15.101.204 with SMTP id bp52mr38431150eeb.31.1362232218031; Sat, 02 Mar 2013 05:50:18 -0800 (PST) Received: from gmail.com (aek101.neoplus.adsl.tpnet.pl. [83.25.114.101]) by mx.google.com with ESMTPS id o3sm22363368eem.15.2013.03.02.05.50.16 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Sat, 02 Mar 2013 05:50:17 -0800 (PST) Date: Sat, 2 Mar 2013 14:50:15 +0100 From: Marcin Jurkowski To: Sven Geggus Cc: Evgeniy Polyakov , linux-kernel@vger.kernel.org Subject: [PATCH 1/1] w1: fix oops when w1_search is called from netlink connector Message-ID: <20130302135015.GA21448@gmail.com> References: <20130116141627.GA23638@ioremap.net> <20130302001103.GB18026@gmail.com> <20130302094510.GA4695@geggus.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130302094510.GA4695@geggus.net> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Mar 02, 2013 at 10:45:10AM +0100, Sven Geggus wrote: > This is the bad commit I found doing git bisect: > 04f482faf50535229a5a5c8d629cf963899f857c is the first bad commit > commit 04f482faf50535229a5a5c8d629cf963899f857c > Author: Patrick McHardy > Date: Mon Mar 28 08:39:36 2011 +0000 Good job. I was too lazy to bisect for bad commit;) Reading the code I found problematic kthread_should_stop call from netlink connector which causes the oops. After applying a patch, I've been testing owfs+w1 setup for nearly two days and it seems to work very reliable (no hangs, no memleaks etc). More detailed description and possible fix is given below: Function w1_search can be called from either kthread or netlink callback. While the former works fine, the latter causes oops due to kthread_should_stop invocation. This patch adds a check if w1_search is serving netlink command, skipping kthread_should_stop invocation if so. Signed-off-by: Marcin Jurkowski --- drivers/w1/w1.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c index 7994d933..7e2220d 100644 --- a/drivers/w1/w1.c +++ b/drivers/w1/w1.c @@ -924,7 +924,8 @@ void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb tmp64 = (triplet_ret >> 2); rn |= (tmp64 << i); - if (kthread_should_stop()) { + /* ensure we're called from kthread and not by netlink callback */ + if (!dev->priv && kthread_should_stop()) { mutex_unlock(&dev->bus_mutex); dev_dbg(&dev->dev, "Abort w1_search\n"); return; -- 1.7.12.4 -- 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/