From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wei Liu Subject: Re: xen-netback: count number required slots for an skb more carefully Date: Wed, 4 Sep 2013 09:41:47 +0100 Message-ID: <20130904084147.GL14104@zion.uk.xensource.com> References: <1378229390-12919-1-git-send-email-david.vrabel@citrix.com> <20130903215328.GA13465@zion.uk.xensource.com> <52269A37.7030600@oracle.com> <20130904060446.GA25227@u109add4315675089e695.ant.amazon.com> <1378283770.17510.52.camel@kazak.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Cc: Matt Wilson , annie li , Wei Liu , David Vrabel , , Konrad Rzeszutek Wilk , Boris Ostrovsky , , To: Ian Campbell Return-path: Received: from smtp02.citrix.com ([66.165.176.63]:8878 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755645Ab3IDIlt (ORCPT ); Wed, 4 Sep 2013 04:41:49 -0400 Content-Disposition: inline In-Reply-To: <1378283770.17510.52.camel@kazak.uk.xensource.com> Sender: netdev-owner@vger.kernel.org List-ID: On Wed, Sep 04, 2013 at 09:36:10AM +0100, Ian Campbell wrote: > On Tue, 2013-09-03 at 23:04 -0700, Matt Wilson wrote: > > On Wed, Sep 04, 2013 at 10:25:59AM +0800, annie li wrote: > > > On 2013-9-4 5:53, Wei Liu wrote: > > [...] > > > >Matt, do you fancy sending the final version? IIRC the commit message > > > >needs to be re-written. I personally still prefer Matt's solution as > > > >it a) make efficient use of the ring, b) uses ring pointers to > > > >calculate slots which is most accurate, c) removes the dependence on > > > >MAX_SKB_FRAGS in guest RX path. > > > > > > > >Anyway, we should get this fixed ASAP. > > Yes. Would there be any harm in just applying David's patch (just > because it is the one currently in our hands and it is based on a recent > enough kernel). It looks right from a correctness PoV to me. > > > > Totally agree. This issue is easy to be reproduced with large MTU. > > > It is better to upstream the fix soon in case others hit it and > > > waste time to fix it. > > > > I'd like to go with Xi's proposed patch that I posed earlier. > > I don't think I saw that, do you have a message-id? > > ("Xi" is a bit too short for a search on my INBOX unfortunately). > This one <1373409659-22383-1-git-send-email-msw@amazon.com> Wei. > > The main > > thing that's kept me from sending a final version is lack of time to > > retest against a newer kernel. > > > > Could someone help out with that? I probably can't get to it until the > > end of the week. > > > > Sorry for the delay. :-( > > > > --msw >