From: Ian Campbell <ijc@hellion.org.uk>
To: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Brian Gerst <brgerst@gmail.com>, Christian Kujau <lists@nerdbynature.de>,
       "H. Peter Anvin" <hpa@zytor.com>, Jeremy Fitzhardinge <jeremy@goop.org>,
       LKML <linux-kernel@vger.kernel.org>
In-Reply-To: <20100110134951.GD5189@lenovo>
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	 <alpine.DEB.2.01.1001060434330.3483@bogon.housecafe.de>
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	 <alpine.DEB.2.01.1001071123220.3483@bogon.housecafe.de>
	 <20100108215039.GD4967@lenovo>
	 <73c1f2161001091750y67a852dfk7539021dcc82fa1f@mail.gmail.com>
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Date: Sun, 10 Jan 2010 14:05:35 +0000
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On Sun, 2010-01-10 at 16:49 +0300, Cyrill Gorcunov wrote:
> On Sun, Jan 10, 2010 at 04:36:28PM +0300, Cyrill Gorcunov wrote:
> ...
> > > 
> > > With just the CS RPL fix below I see a GPF at kernel_thread_helper with
> > > SS=3 (hence my hypothesis about NULL selectors and non-zero RPL above).
> > > With both the SS and CS fixes things work fine.
> > 
> > any of CS,SS loaded with NULL descriptor should lead to #GP
> > 
> 
> though SS with RPL=0 is allowed to be NULL descriptor in 64bit mode

yes, that's what I meant.

Ian.

-- 
Ian Campbell

Tussman's Law:
	Nothing is as inevitable as a mistake whose time has come.

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