Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757037AbZCXPru (ORCPT ); Tue, 24 Mar 2009 11:47:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754788AbZCXPri (ORCPT ); Tue, 24 Mar 2009 11:47:38 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:41577 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753430AbZCXPrh (ORCPT ); Tue, 24 Mar 2009 11:47:37 -0400 Date: Tue, 24 Mar 2009 16:47:17 +0100 From: Ingo Molnar To: Herbert Xu Cc: Robert Schwebel , Linus Torvalds , Frank Blaschka , "David S. Miller" , Thomas Gleixner , Peter Zijlstra , Linux Kernel Mailing List , kernel@pengutronix.de Subject: Re: Revert "gro: Fix legacy path napi_complete crash", (was: Re: Linux 2.6.29) Message-ID: <20090324154717.GA7506@elte.hu> References: <20090324130202.GA32469@elte.hu> <20090324143303.GP5367@pengutronix.de> <20090324143942.GA20462@elte.hu> <20090324150928.GB30224@gondor.apana.org.au> <20090324153616.GA31143@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090324153616.GA31143@elte.hu> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1593 Lines: 41 * Ingo Molnar wrote: > > * Herbert Xu wrote: > > > On Tue, Mar 24, 2009 at 03:39:42PM +0100, Ingo Molnar wrote: > > > > > > Subject: [PATCH] net: Fix netpoll lockup in legacy receive path > > > > Actually, this patch is still racy. If some interrupt comes in > > and we suddenly get the maximum amount of backlog we can still > > hang when we call __napi_complete incorrectly. It's unlikely > > but we certainly shouldn't allow that. Here's a better version. > > > > net: Fix netpoll lockup in legacy receive path > > ok - i'm testing with this now. test failure on one of the boxes, interface got stuck after ~100K packets: eth1 Link encap:Ethernet HWaddr 00:13:D4:DC:41:12 inet addr:10.0.1.13 Bcast:10.0.1.255 Mask:255.255.255.0 inet6 addr: fe80::213:d4ff:fedc:4112/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:22555 errors:0 dropped:0 overruns:0 frame:0 TX packets:1897 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:2435071 (2.3 MiB) TX bytes:503790 (491.9 KiB) Interrupt:11 Base address:0x4000 i'm going back to your previous version for now - it might still be racy but it worked well for about 1.5 hours of test-time. Ingo -- 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/