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Date: Tue, 22 Apr 2014 10:24:59 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Andrew Lutomirski <amluto@gmail.com>
CC: Linus Torvalds <torvalds@linux-foundation.org>,
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        Alexandre Julliard <julliard@winehq.com>,
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Subject: Re: [PATCH] x86-64: espfix for 64-bit mode *PROTOTYPE*
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On 04/22/2014 10:20 AM, Andrew Lutomirski wrote:
> 
> It won't, given the above.  I misunderstood what you were checking.
> 
> It still seems to me that only #GP needs this special handling.  The
> IST entries should never run on the espfix stack, and #MC, #DB, #NM,
> and #SS (I missed that one earlier) use IST.
> 
> Would it ever make sense to make #GP use IST as well?  That might
> allow espfix_adjust_stack to be removed entirely.  I don't know how
> much other fiddling would be needed to make that work.
> 

Interesting thought.  It might even be able to share an IST entry with #SS.

	-hpa