From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: [PATCH] [RFC] More fp instructions for realmode
	emulation (Enables booting OS/2 as a HVM guest on Intel/VT hardware)
Date: Mon, 3 Mar 2008 17:59:29 +0100
Message-ID: <20080303165929.GC9853@one.firstfloor.org>
References: <p73bq5v7tc3.fsf@bingen.suse.de>
	<C3F1C324.1D5A0%keir.fraser@eu.citrix.com>
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To: Keir Fraser <keir.fraser@eu.citrix.com>
Cc: Andi Kleen <andi@firstfloor.org>, Trolle Selander <trolle.selander@gmail.com>, xen-devel <xen-devel@lists.xensource.com>
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On Mon, Mar 03, 2008 at 03:00:52PM +0000, Keir Fraser wrote:
> On 3/3/08 14:52, "Andi Kleen" <andi@firstfloor.org> wrote:
> 
> >> Intel SDM Volume 1 Section 8.6 (?X87 FPU Exception Synchronization?) is very
> >> helpful in this regard. It confirms my suspicions, that we will need to wrap
> >> the FPU inline asms in some fixup glue. The only exceptions to this rule are
> > 
> > Yes you definitely need to. That was a kernel crash bug on native Linux
> > some time ago...
> > 
> > Also you need to do the same for any FXSAVEs/FXRSTORs if you haven't already.
> 
> FXSAVE/FXRSTOR do not flush pending FPU exceptions, right?

Yes they do not, but there are other ways to make them #GP

-Andi