linux-kernel - Re: [RFC PATCH 3/3] boot bzImages under paravirt

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:	Fri, 04 May 2007 11:25:48 -0700
From:	Jeremy Fitzhardinge <jeremy@...p.org>
To:	"Eric W. Biederman" <ebiederm@...ssion.com>
CC:	Rusty Russell <rusty@...tcorp.com.au>, Andi Kleen <ak@...e.de>,
	Chris Wright <chrisw@...s-sol.org>,
	Zachary Amsden <zach@...are.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	"H. Peter Anvin" <hpa@...or.com>,
	lkml - Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [RFC PATCH 3/3] boot bzImages under paravirt

Eric W. Biederman wrote:
>>> load the segments as well.
>>>
>>> Gujin looks like it loads just %es and %ds.
>>>   
>>>       
>> We should be able to make do with that until we've got our own gdt.
>>     
>
> Right after the segments loads we have:
> 	leal 0x40(%esi), %esp
> 	call 1f
> 1:	popl %ebp
> 	subl $1b, %ebp
>
> That uses %ss and %ds.  Can we use a segment override on a call
> instruction?
>   

I overlooked Gujin missing %ss.  That's harsh.  Easy for them to fix,
presumably.

> Yes.  Exactly like we do for real mode code, and with exactly the same
> values.  Just in a little different format.

Well, fits in well with Xen's requirements, since it wants ELF notes
there for exactly the same reason.

    J
-
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/