From mboxrd@z Thu Jan  1 00:00:00 1970
From: Matthew Wilcox <willy-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
Subject: What is the meaning of PASID_MIN?
Date: Mon, 11 Feb 2019 11:28:04 -0800
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I'm looking at commit 562831747f6299abd481b5b00bd4fa19d5c8a259
which fails to adequately explain why we can't use PASID 0.  Commit
af39507305fb83a5d3c475c2851f4d59545d8a18 also doesn't explain why PASID
0 is no longer usable for the intel-svm driver.

There are a load of simplifications that could be made to this, but I
don't know which ones to suggest without a clear understanding of the
problem you're actually trying to solve.