From: Doug Ledford <dledford@redhat.com>
To: Bart Van Assche <bvanassche@acm.org>,
Steve Wise <larrystevenwise@gmail.com>,
linux-rdma@vger.kernel.org, 3100102071@zju.edu.cn,
leon@kernel.org
Subject: Re: [PATCH 2/2] rxe: correctly calculate iCRC for unaligned payloads
Date: Tue, 03 Dec 2019 19:46:47 -0500 [thread overview]
Message-ID: <0f8d9087c48e986d08cf85ef8b59bdca25425eaa.camel@redhat.com> (raw)
In-Reply-To: <a0003c88-10f5-c14a-220d-c100fa160163@acm.org>
[-- Attachment #1: Type: text/plain, Size: 1478 bytes --]
On Tue, 2019-12-03 at 08:25 -0800, Bart Van Assche wrote:
> On 12/2/19 6:03 PM, Steve Wise wrote:
> > If RoCE PDUs being sent or received contain pad bytes, then the iCRC
> > is miscalculated resulting PDUs being emitted by RXE with an
> > incorrect
> > iCRC, as well as ingress PDUs being dropped due to erroneously
> > detecting
> > a bad iCRC in the PDU. The fix is to include the pad bytes, if any,
> > in iCRC computations.
>
> Should this description mention that this patch breaks compatibility
> with SoftRoCE drivers that do not include this fix? Do we need a
> kernel
> module parameter that allows to select either the old or the new
> behavior?
No. The original soft-RoCE driver was supposed to be compatible with
hardware devices. Because of this bug, it obviously wasn't. This is a
bug fix, and we do not need to do anything to be compatible with the
broken behavior. Instead, it just needs noting that the soft-RoCE
implementation in prior kernels has a known wire format bug that impacts
communications with both fixed versions of the driver and real hardware
devices.
> > CC: bvanassche@acm.org,3100102071@zju.edu.cn,leon@kernel.org
>
> Should this Cc-line perhaps be converted into three Cc-lines?
>
> Otherwise this patch looks fine to me.
>
> Thanks,
>
> Bart.
>
--
Doug Ledford <dledford@redhat.com>
GPG KeyID: B826A3330E572FDD
Fingerprint = AE6B 1BDA 122B 23B4 265B 1274 B826 A333 0E57 2FDD
[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
next prev parent reply other threads:[~2019-12-04 0:47 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-03 2:03 [PATCH 1/2] Update mailmap info for Steve Wise Steve Wise
2019-12-03 2:03 ` [PATCH 2/2] rxe: correctly calculate iCRC for unaligned payloads Steve Wise
2019-12-03 16:25 ` Bart Van Assche
2019-12-03 18:32 ` Steve Wise
2019-12-04 0:46 ` Doug Ledford [this message]
2019-12-09 19:07 ` Doug Ledford
2019-12-10 6:54 ` Leon Romanovsky
2019-12-11 4:24 ` Doug Ledford
2019-12-11 5:59 ` Leon Romanovsky
2019-12-11 14:42 ` Tom Talpey
2019-12-12 22:06 ` Doug Ledford
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=0f8d9087c48e986d08cf85ef8b59bdca25425eaa.camel@redhat.com \
--to=dledford@redhat.com \
--cc=3100102071@zju.edu.cn \
--cc=bvanassche@acm.org \
--cc=larrystevenwise@gmail.com \
--cc=leon@kernel.org \
--cc=linux-rdma@vger.kernel.org \
/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).