From: Ralf Baechle <ralf@linux-mips.org>
To: Daniel Jacobowitz <dan@debian.org>
Cc: linux-mips@linux-mips.org
Subject: Re: [PATCH] Fix TCP/UDP checksums on the Broadcom SB-1
Date: Tue, 20 Sep 2005 12:01:02 +0100 [thread overview]
Message-ID: <20050920110101.GA3159@linux-mips.org> (raw)
In-Reply-To: <20050920032818.GA7199@nevyn.them.org>
On Mon, Sep 19, 2005 at 11:28:18PM -0400, Daniel Jacobowitz wrote:
> The type of sum in csum_tcpudp_nofold is "unsigned int", so when we assign
> to it in an asm() block, and we're running on a system with 64-bit
> registers, it is vitally important that we sign extend it correctly before
> returning to C. Otherwise the stray high bits will be preserved into
> csum_fold, and on the SB-1 processor, 32-bit arithmetic on a non
> sign-extended register will yield surprising results.
>
> This caused incorrect checksums in some UDP packets for NFS root. The
> problem was mild when using a 10.0.1.x IP address, but severe when
> using 192.168.1.x.
Good catch. And just to increase the func factor this bug did also apply
to 2.4. Applied,
Ralf
prev parent reply other threads:[~2005-09-20 11:01 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-09-20 3:28 [PATCH] Fix TCP/UDP checksums on the Broadcom SB-1 Daniel Jacobowitz
2005-09-20 10:43 ` Maciej W. Rozycki
2005-09-20 11:00 ` Matej Kupljen
2005-09-20 11:06 ` Ralf Baechle
2005-09-20 14:26 ` Michael Uhler
2005-09-20 14:26 ` Michael Uhler
2005-09-20 14:59 ` Ralf Baechle
2005-09-20 11:01 ` Ralf Baechle [this message]
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=20050920110101.GA3159@linux-mips.org \
--to=ralf@linux-mips.org \
--cc=dan@debian.org \
--cc=linux-mips@linux-mips.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.