linux-kernel - Re: [PATCH 5/9] x86/dumpstack: Improve opcodes dumping in the Code: section

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:   Wed, 7 Mar 2018 15:16:47 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     Josh Poimboeuf <jpoimboe@...hat.com>
Cc:     Linus Torvalds <torvalds@...ux-foundation.org>,
        X86 ML <x86@...nel.org>, Andy Lutomirski <luto@...capital.net>,
        Peter Zijlstra <peterz@...radead.org>,
        LKML <linux-kernel@...r.kernel.org>,
        Chuck Ebbert <cebbert.lkml@...il.com>
Subject: Re: [PATCH 5/9] x86/dumpstack: Improve opcodes dumping in the Code:
 section

On Wed, Mar 07, 2018 at 07:25:35AM -0600, Josh Poimboeuf wrote:
> How about we just remove the 'code_bytes=' option?

Haha, removing stuff is my usual solution :-)

I'd love to.

> (Or at the very
> least, reduce its possible range to a reasonable max?)
> 
> I doubt anybody actually uses it.  I'd never heard of it before, nor
> have I ever seen an oops with a long code dump.  I can't fathom why
> somebody would even need it.  64 bytes is plenty, and an 8k code dump
> just sounds insane.

Yeah, I see a Chuck Ebbert in git log output with a gmail account, maybe
that's the same person. (I've assumed he's not at RH anymore, otherwise
you would've CCed him :-)).

Let's ask him. CCed.

> It comes from the following commit:
> 
> commit 86c418374223be3f328b5522545196db02c8ceda
> Author: Chuck Ebbert <cebbert@...hat.com>
> Date:   Tue Feb 13 13:26:25 2007 +0100
> 
>     [PATCH] i386: add option to show more code in oops reports
> 
>     Sometimes developers need to see more object code in an oops report,
>     e.g. when kernel may be corrupted at runtime.
> 
>     Add the "code_bytes" option for this.
> 
>     Signed-off-by: Chuck Ebbert <cebbert@...hat.com>
>     Signed-off-by: Andi Kleen <ak@...e.de>
>     Cc: Andi Kleen <ak@...e.de>
>     Signed-off-by: Andrew Morton <akpm@...ux-foundation.org>
> 
> But I've never seen a case where somebody needed to use it.
> 
> -- 
> Josh

-- 
Regards/Gruss,
    Boris.

Good mailing practices for 400: avoid top-posting and trim the reply.