netdev - Re: [PATCH net] net: mvneta: fix operation for 64K PAGE

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 17 Dec 2018 00:25:58 +0100
From:   Marcin Wojtas <mw@...ihalf.com>
To:     David Miller <davem@...emloft.net>
Cc:     Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        linux-arm-kernel@...ts.infradead.org,
        netdev <netdev@...r.kernel.org>,
        Russell King - ARM Linux <linux@...linux.org.uk>,
        Maxime Chevallier <maxime.chevallier@...tlin.com>,
        Thomas Petazzoni <thomas.petazzoni@...tlin.com>,
        Grégory Clement <gregory.clement@...tlin.com>,
        Antoine Tenart <antoine.tenart@...tlin.com>,
        Stefan Chulski <stefanc@...vell.com>, nadavh@...vell.com,
        Grzegorz Jaszczyk <jaz@...ihalf.com>
Subject: Re: [PATCH net] net: mvneta: fix operation for 64K PAGE_SIZE

Hi David,

niedz., 16 gru 2018 o 21:41 David Miller <davem@...emloft.net> napisał(a):
>
> From: Marcin Wojtas <mw@...ihalf.com>
> Date: Tue, 11 Dec 2018 13:56:49 +0100
>
> > Recent changes in the mvneta driver reworked allocation
> > and handling of the ingress buffers to use entire pages.
> > Apart from that in SW BM scenario the HW must be informed
> > via PRXDQS about the biggest possible incoming buffer
> > that can be propagated by RX descriptors.
> >
> > The BufferSize field was filled according to the MTU-dependent
> > pkt_size value. Later change to PAGE_SIZE broke RX operation
> > when usin 64K pages, as the field is simply too small.
> >
> > This patch conditionally limits the value passed to the BufferSize
> > of the PRXDQS register, depending on the PAGE_SIZE used.
> > On the occasion remove now unused frag_size field of the mvneta_port
> > structure.
> >
> > Fixes: 562e2f467e71 ("net: mvneta: Improve the buffer allocation method for SWBM")
> > Signed-off-by: Marcin Wojtas <mw@...ihalf.com>
>
> The discussion died on this, but the bug should be fixed.
>
> So in the short term I am applying this and queueing it up for v4.19
> -stable.
>
> Thanks.

Thanks. Indeed, the patch is valid as a fix for current version of SW
BM. However, because this concept is broken, I will rework it and
submit patch/patches some time early 2019.

Best regards,
Marcin