linux-kernel - Re: [PATCH] i386: always clear bss

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]

Message-ID: <m1hcqspg7c.fsf@ebiederm.dsl.xmission.com>
Date:	Fri, 04 May 2007 13:00:07 -0600
From:	ebiederm@...ssion.com (Eric W. Biederman)
To:	"H. Peter Anvin" <hpa@...or.com>
Cc:	Jeremy Fitzhardinge <jeremy@...p.org>,
	Rusty Russell <rusty@...tcorp.com.au>, Andi Kleen <ak@...e.de>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] i386: always clear bss

"H. Peter Anvin" <hpa@...or.com> writes:

> Eric W. Biederman wrote:
>>> Oh, right.  And this runs with interrupts off, so you only need one
>>> dword.  That's fine, of course, although the location is a bit awkward.
>> 
>> Yep.  That is what I found when surveyed the available locations.
>
> Look at the structure definition I just posted; I think you'll find that
> using something not in the immediate extension area for the video area
> would have been preferrable, I would suggest 0x5c or 0x1e4.

My notes show 0x5c reserved for additional apm_bios_info, although
of the top of my head I don't know how realistic that is.

0x1e4 does look available.

It has been a long time since I made that choice, and I do see that
looking at struct screen_info I did remember to document that I was
using 0x3c, even in your structure.

It is all internal to our boot process and external code isn't going
to use it so we can change it if we feel like.

Eric
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/