From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH 6/10] lguest code: the little linux hypervisor.
Date: Fri, 09 Feb 2007 14:29:12 -0800 (PST)
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From: Andi Kleen <ak@muc.de>
Date: Fri, 9 Feb 2007 12:50:06 +0100

> 
> > Yes, it is a bit, umm, innovative.  If it is going to be kept, even if 
> > just for devel logging, you should disable interrupts around it.  
> > Changing segments is not a normal thing to do.
> 
> Actually that wouldn't be needed because interrupts are not allowed to do any 
> user accesses. And contrary to the name it doesn't actually change
> the segment registers, only state used by *_user.

That's right and we use this construct all throughout the
syscall compatibility layer for 64-bit platforms.