Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751479Ab1BDMFt (ORCPT ); Fri, 4 Feb 2011 07:05:49 -0500 Received: from nbd.name ([46.4.11.11]:36534 "EHLO nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751098Ab1BDMFs (ORCPT ); Fri, 4 Feb 2011 07:05:48 -0500 Message-ID: <4D4BEB99.4060202@openwrt.org> Date: Fri, 04 Feb 2011 13:05:45 +0100 From: Felix Fietkau User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-US; rv:1.9.2.13) Gecko/20101207 Thunderbird/3.1.7 MIME-Version: 1.0 To: Dmitry Torokhov CC: Miklos Szeredi , linux-kernel@vger.kernel.org, linux-wireless@vger.kernel.org, "John W. Linville" Subject: Re: Wireless regression (was 2.6.38-rc3: FUSE (sshfs) hangs under load) References: <20110201175452.GB518@core.coreip.homeip.net> <20110202165236.GA3178@core.coreip.homeip.net> <20110203065541.GB5592@core.coreip.homeip.net> <20110203194115.GA14159@core.coreip.homeip.net> <20110204064952.GA12914@core.coreip.homeip.net> <4D4BE5D7.8090202@openwrt.org> In-Reply-To: <4D4BE5D7.8090202@openwrt.org> X-Enigmail-Version: 1.1.1 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3505 Lines: 82 On 2011-02-04 12:41 PM, Felix Fietkau wrote: > On 2011-02-04 7:49 AM, Dmitry Torokhov wrote: >> On Thu, Feb 03, 2011 at 11:41:15AM -0800, Dmitry Torokhov wrote: >>> On Thu, Feb 03, 2011 at 12:13:24PM +0100, Miklos Szeredi wrote: >>> > On Wed, 2 Feb 2011, Dmitry Torokhov wrote: >>> > > On Wed, Feb 02, 2011 at 08:52:36AM -0800, Dmitry Torokhov wrote: >>> > > > On Wed, Feb 02, 2011 at 12:52:36PM +0100, Miklos Szeredi wrote: >>> > > > > On Tue, 1 Feb 2011, Dmitry Torokhov wrote: >>> > > > > > Hi, >>> > > > > > >>> > > > > > After installing 2.6.38-rc3 (plus a few input patches) sshfs started to >>> > > > > > misbehave on me under load. It starts off fine but when I try to compile >>> > > > > > a few modules against kernel sources residing on the other box the >>> > > > > > processes go into 'D' state and just sit there doing nothing. >>> > > > > >>> > > > > Can you please post a stack trace from SysRq-T? >>> > > > > >>> > > > >> ... >>> > > >>> > > OK, so here are the stack traces you requested. First one is snapshot of >>> > > when compile got stuck, the 2nd one is when I interrupted make which >>> > > caused gcc to go to 'D' state. >>> > >>> > There doesn't appear anything abnormal there. >>> > >>> > It's going into D state after it has received an interrupt and sent it >>> > along to the userspace filesystem. Then it will go into >>> > uninterruptible sleep until the answer is received. >>> > >>> > So the hang is because the answer to an open request is not being >>> > received. I can't tell where it got stuck, apparently not anywhere on >>> > the local machine. >>> > >>> > Can you please get a log from sshfs with "-odebug,sshfs_debug" and >>> > redirect stderr to a file? That might tell a bit more about the >>> > situation. Or it might not... >>> >>> Hmm, it might be just the network itself, last night mutt in ssh session >>> froze on me as well. I guess I'll just have to finish my bisect >>> exercise. >>> >> >> I finished bisecting and it turned out that the problematic commit >> happened to be in wireless (I have iwl3945): >> >> commit 4cd06a344db752f513437138953af191cbe9a691 >> Author: Felix Fietkau >> Date: Sat Dec 18 19:30:49 2010 +0100 >> >> mac80211: skip unnecessary pskb_expand_head calls >> >> If the skb is not cloned and we don't need any extra headroom, there >> is no point in reallocating the skb head. >> >> Signed-off-by: Felix Fietkau >> Signed-off-by: John W. Linville >> >> With this commit reverted from 2.6.38-rc3 I can not reproduce sshfs >> getting stuck here. > I really don't see how this commit could be causing these issues, and > I'm not aware of any similar issues affecting other drivers. Could you please try this patch to see if it fixes the issue as well? diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index ffc6749..3168eae 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1547,7 +1547,7 @@ static int ieee80211_skb_resize(struct ieee80211_local *local, skb_orphan(skb); } - if (skb_header_cloned(skb)) + if (skb_cloned(skb)) I802_DEBUG_INC(local->tx_expand_skb_head_cloned); else if (head_need || tail_need) I802_DEBUG_INC(local->tx_expand_skb_head); -- 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/