From: Andi Kleen <ak@suse.de>
To: Zachary Amsden <zach@vmware.com>
Subject: Re: [patch] i386: remove IOPL check on task switch
Date: Fri, 3 Nov 2006 19:41:28 +0100
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Cc: Chuck Ebbert <76306.1226@compuserve.com>,
       linux-kernel <linux-kernel@vger.kernel.org>,
       Linus Torvalds <torvalds@osdl.org>, Andrew Morton <akpm@osdl.org>
References: <200611030130_MC3-1-D02A-DEB@compuserve.com> <454B850C.3050402@vmware.com>
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> Nack.  This is used for paravirt-ops kernels that use IOPL'd userspace.  
> Fixing it would require a fairly heavy penalty on the iret path, since 
> every single instruction there contributes to a critical region which 
> must have custom fixup code, or some other technique to provide 
> protection against interrupt re-entrancy.
> 
> At least, let's discuss other potential solutions first - for now it is 
> harmless.

Ok I will drop the patch again

-Andi
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