linux-kernel - Re: amdgpu: Corrupted video on 32 bit systems (possible fix)

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] [day] [month] [year] [list]

Message-ID: <20170120120704.GA11366@teela.fritz.box>
Date:   Fri, 20 Jan 2017 13:07:05 +0100
From:   Nils Holland <nholland@...ys.org>
To:     Michel Dänzer <michel@...nzer.net>
Cc:     amd-gfx@...ts.freedesktop.org, linux-kernel@...r.kernel.org,
        dri-devel@...ts.freedesktop.org
Subject: Re: amdgpu: Corrupted video on 32 bit systems (possible fix)

On Fri, Jan 20, 2017 at 06:11:50PM +0900, Michel Dänzer wrote:
> On 20/01/17 04:44 PM, Nils Holland wrote:
> > 
> > Sounds like a good idea! I was a bit heasitant because, to be honest,
> > I'm not at all an expert about the code in question and basically only
> > saw how you fixed the issue in radeon and thought: "Well, let's see if
> > I can do the same thing in amdgpu and if so, if it helps there, too".
> > ;-)
> > 
> > However, since you've said that a 32 bit fix in amdgpu generally seems
> > like a good idea,
> 
> Actually, unless your CPU can't run 64-bit code, I'd say running a
> 64-bit kernel would be an overall even better idea for you, even with
> 32-bit userspace. :) Anyway, this problem clearly needs to be fixed.

Yep, that's certainly true! However, I have to admit that I'm
intentionally regularly testing all kinds of stuff on pure 32 bit,
because I think that most of the other "first like of testing", i.e.
the developers themselves, are primarily working with 64 bit these
days. So I thought it might make sense if someone keeps a little of an
eye on 32 bit - after all, in general and if there are no technical
reasons that speak agsinst it, things should work there, too. And
indeed, during the past year I've spotted a few little things that
were only causing problems on 32 bit - both in the kernel and other
components like systemd - and which could subsequently be fixed in a
relatively easy manner.

> > I would indeed use a little time on the weekend to get a proper patch
> > ready and submit it for review. Even if the "no wc for x86_32" part is
> > probably the only thing it'll contain
> 
> I wouldn't bother with that. There is no real reason against bringing it
> all over in one go.

Right, I'll see what I can do over the weekend. So stay tuned for my
first ever proper (at least as far as the guidelines for submitting
patches are concerned) patch and expect the worst. ;-)

Greetings
Nils