From: Stephen Hemminger <shemminger@linux-foundation.org>
To: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Roopa Prabhu <roprabhu@cisco.com>,
Dumazet <eric.dumazet@gmail.com>, Jiri Pirko <jpirko@redhat.com>,
e1000-devel@lists.sourceforge.net, netdev@vger.kernel.org,
Vasanthy, Jie Yang <Jie.Yang@atheros.com>,
Eric, Kolluri <vkolluri@cisco.com>,
"VMware, Inc." <pv-drivers@vmware.com>,
Brice Goglin <brice@myri.com>,
H, Andrew Gallatin <gallatin@myri.com>,
Joe Perches <joe@perches.com>, David Wang <dwang2@cisco.com>,
Shreyas Bhatewara <sbhatewara@vmware.com>,
"David S. Miller" <davem@davemloft.net>,
Sweeten <hsweeten@visionengravers.com>
Subject: Re: [PATCH 3/3] net: Fix drivers advertising HW_CSUM feature to use csum_start
Date: Wed, 15 Dec 2010 10:25:36 -0800 [thread overview]
Message-ID: <20101215102536.6430274b@nehalam> (raw)
In-Reply-To: <20101215181655.GA29962@rere.qmqm.pl>
On Wed, 15 Dec 2010 19:16:55 +0100
Michał Mirosław <mirq-linux@rere.qmqm.pl> wrote:
> On Tue, Dec 14, 2010 at 07:07:27PM -0800, Stephen Hemminger wrote:
> > On Wed, 15 Dec 2010 02:24:08 +0100 (CET)
> > Michał Mirosław <mirq-linux@rere.qmqm.pl> wrote:
> > > Some drivers are using skb_transport_offset(skb) instead of skb->csum_start
> > > for NETIF_F_HW_CSUM offload. This does not matter now, but if someone
> > > implements checksumming of encapsulated packets then this will break silently.
> > >
> > > TSO output paths are left as they are, since they are for IP+TCP only
> > > (might be worth converting though).
> > >
> > > Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
> > Which if any of these drivers did you test on real hardware?
>
> I'm running it on skge, with additional patch that changes it to use
> NETIF_F_HW_CSUM instead of NETIF_F_IP_CSUM. BTW, why it is not advertising
> full HW checksum in vanilla kernel? Are there any known hardware bugs in there?
>
> Best Regards,
> Michał Mirosław
The driver was written from vendor sk98lin driver and that driver
only did IP checksum, therefore I did not trust the hardware.
The chipset is old, and not used in new designs, no documentation
is up to date (and I didn't have any).
Please don't enable non-IPv4 checksum offload on this hardware, there
is too big a risk of it not working on all hardware.
--
------------------------------------------------------------------------------
Lotusphere 2011
Register now for Lotusphere 2011 and learn how
to connect the dots, take your collaborative environment
to the next level, and enter the era of Social Business.
http://p.sf.net/sfu/lotusphere-d2d
_______________________________________________
E1000-devel mailing list
E1000-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/e1000-devel
To learn more about Intel® Ethernet, visit http://communities.intel.com/community/wired
next prev parent reply other threads:[~2010-12-15 18:25 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-12-15 1:24 [PATCH 0/3] Fix NETIF_F_HW_CSUM implementations [v2] Michał Mirosław
2010-12-15 1:24 ` [PATCH 2/3] net: Use skb_checksum_start_offset() Michał Mirosław
2010-12-15 1:24 ` [PATCH 3/3] net: Fix drivers advertising HW_CSUM feature to use csum_start Michał Mirosław
2010-12-15 3:07 ` Stephen Hemminger
2010-12-15 18:16 ` Michał Mirosław
2010-12-15 18:25 ` Stephen Hemminger [this message]
2010-12-15 18:58 ` Michał Mirosław
2010-12-15 1:24 ` [PATCH 1/3] net: Introduce skb_checksum_start_offset() Michał Mirosław
2010-12-15 1:29 ` [PATCH 0/3] Fix NETIF_F_HW_CSUM implementations [v2] David Miller
2010-12-16 22:43 ` David Miller
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20101215102536.6430274b@nehalam \
--to=shemminger@linux-foundation.org \
--cc=Jie.Yang@atheros.com \
--cc=brice@myri.com \
--cc=davem@davemloft.net \
--cc=dwang2@cisco.com \
--cc=e1000-devel@lists.sourceforge.net \
--cc=eric.dumazet@gmail.com \
--cc=gallatin@myri.com \
--cc=hsweeten@visionengravers.com \
--cc=joe@perches.com \
--cc=jpirko@redhat.com \
--cc=mirq-linux@rere.qmqm.pl \
--cc=netdev@vger.kernel.org \
--cc=pv-drivers@vmware.com \
--cc=roprabhu@cisco.com \
--cc=sbhatewara@vmware.com \
--cc=vkolluri@cisco.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).