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 for Android: free password hash cracker in your pocket
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Sun, 31 Aug 2008 12:27:51 -0700
From:	Arjan van de Ven <arjan@...radead.org>
To:	Linus Torvalds <torvalds@...ux-foundation.org>
Cc:	David Sanders <linux@...dersweb.net>, linux-kernel@...r.kernel.org,
	Jan Beulich <jbeulich@...ell.com>, Andi Kleen <ak@...e.de>,
	Ingo Molnar <mingo@...e.hu>,
	Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [BUG] x86 kenel won't boot under Virtual PC

On Sun, 31 Aug 2008 11:47:04 -0700 (PDT)
Linus Torvalds <torvalds@...ux-foundation.org> wrote:

> 
> 
> On Sun, 31 Aug 2008, David Sanders wrote:
> >
> > I recently discovered that x86 kernels won't boot under Virtual PC.
> 
> What CPU does Virtual PC emulate? As far as Wikipedia is concerned
> (not that I'd take it on complete faith) it emulates a 32-bit Intel
> Pentium II.
> 
> And that commit makes the kernel use the "P6 nops" for such hardware. 
> Maybe Virtual PC doesn't support the newer intel nop things?
> 
> Intel docs say that it should be available on any intel CPU that has 
> CPUID.01H.EAX[11:8] = 0110B or 1111B. That's the "family ID", and
> Pentium II should have a family ID of 6 (ie that 0110B case).
> 
> So it sounds like a Virtual PC bug, but I dunno. And maybe we should
> just use the legcay nops for anything that isn't modern (ie P4+ or
> Core)?

it's probably even a security bug in that I don't see what would be
stopping a ring 3 user process from executing these instructions...

--
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/

Powered by blists - more mailing lists