From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Galbraith Subject: Re: netxen: box stuck in netxen_napi_disable() Date: Thu, 22 Jan 2015 09:37:01 +0100 Message-ID: <1421915821.5286.71.camel@marge.simpson.net> References: <1421901805.5286.37.camel@marge.simpson.net> <1421906274.4832.35.camel@edumazet-glaptop2.roam.corp.google.com> <1421907358.5286.42.camel@marge.simpson.net> <1421909520.3471.2.camel@edumazet-glaptop2.roam.corp.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev To: Eric Dumazet Return-path: Received: from mail-wi0-f172.google.com ([209.85.212.172]:61871 "EHLO mail-wi0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750861AbbAVIhG (ORCPT ); Thu, 22 Jan 2015 03:37:06 -0500 Received: by mail-wi0-f172.google.com with SMTP id bs8so41876342wib.5 for ; Thu, 22 Jan 2015 00:37:04 -0800 (PST) In-Reply-To: <1421909520.3471.2.camel@edumazet-glaptop2.roam.corp.google.com> Sender: netdev-owner@vger.kernel.org List-ID: On Wed, 2015-01-21 at 22:52 -0800, Eric Dumazet wrote: > On Thu, 2015-01-22 at 07:15 +0100, Mike Galbraith wrote: > > On Wed, 2015-01-21 at 21:57 -0800, Eric Dumazet wrote: > > > > > This driver doesn't follow the NAPI model correctly. > > > > > > Please try following fix : > > > > Thanks Eric, I'll plug it in in a bit and poke at it. No news is good > > news, as good as news gets for unknown repeatability bugs that is ;-) > > To trigger the bug, all you had to do was to stress the transmit side. Nope, it's easier than that... > You could reduce MAX_STATUS_HANDLE from 64 to 4 to trigger it even > faster. Wow, that made it amazingly easy to verify. With MAX_STATUS_HANDLE=4, without your patch applied box hangs as soon as I bring the network up. Add your patch on top, all is peachy. Fresh boot, or rmmod/modprobe and network restart, doesn't matter, box works with your patch, is dead without it. Here's an ornament for the fix if you think it'll look prettier :) Reported-and-tested-by: Mike Galbraith -Mike