WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Xen

xen-devel

[Top] [All Lists]

Re: [Xen-devel] network misbehaviour with gplpv and 2.6.30

To: James Harper <james.harper@xxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] network misbehaviour with gplpv and 2.6.30
From: Paul Durrant <paul.durrant@xxxxxxxxxx>
Date: 2009年7月21日 10:35:34 +0100
Cc: "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>, Lyon <andrew.lyon@xxxxxxxxx>, Andrew
Delivery-date: 2009年7月21日 02:35:45 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <AEC6C66638C05B468B556EA548C1A77D016DDD27@trantor >
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <AEC6C66638C05B468B556EA548C1A77D016DDD27@trantor >
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Thunderbird 2.0.0.22 (Windows/20090605)
James Harper wrote:
With GPLPV under 2.6.30, GPLPV gets the following from the ring:
ring slot n (first buffer):
 status (length) = 54 bytes
 offset = 0
 flags = NETRXF_extra_info (possibly csum too but not relevant)
ring slot n + 1 (extra info)
 gso.size (mss) = 1460
Because NETRXF_extra_info is not set, that's all I get for that packet.
I assume you mean NETRXF_more_data here? Are you saying that ring slot n has only NETRXF_extra_info and *not* NETRXF_more_data?
In the IP header though, the total length is 1544 (which in itself is a
little strange), but obviously I'm not getting a full packet, just the
ETH+IP+TCP header.
According to Andrew Lyon it works fine in previous versions, so this
problem only arises on 2.6.30. I don't know if netfront on Linux suffers
from a similar problem.
I can't identify any changes that could cause this, but if the problem
is in netback either the frags count isn't being set correctly, or
skb->cb (which appears to be used temporarily to hold nr_frags) is
becoming corrupt (set to 0) somehow, but the window where this could
occur is very small and I can't see where it could happen.
Any suggestions as to where to start looking?
(one nice thing is that I have identified a crash that would occur when
the IP header lied about its length!)
Thanks
James
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
--
===============================
Paul Durrant, Software Engineer
Citrix Systems (R&D) Ltd.
First Floor, Building 101
Cambridge Science Park
Milton Road
Cambridge CB4 0FY
United Kingdom
TEL: x35957 (+44 1223 225957)
===============================
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
<Prev in Thread] Current Thread [Next in Thread>
Previous by Date: Re: [Xen-devel] New release candidates for 3.3.2 and 3.4.1 , Simon Horman
Next by Date: Re: [Xen-devel] [PATCH] stubdom: use TARGET_PAGE_SIZE , Stefano Stabellini
Previous by Thread: [Xen-devel] Re: network misbehaviour with gplpv and 2.6.30 , Andrew Lyon
Next by Thread: RE: [Xen-devel] network misbehaviour with gplpv and 2.6.30 , James Harper
Indexes: [Date] [Thread] [Top] [All Lists]

Copyright ©, Citrix Systems Inc. All rights reserved. Legal and Privacy
Citrix This site is hosted by Citrix

AltStyle によって変換されたページ (->オリジナル) /