From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dave Hansen <dave.hansen@intel.com>
Subject: Re: Should SEV-ES #VC use IST? (Re: [PATCH] Allow RDTSC and RDTSCP
 from userspace)
Date: Tue, 23 Jun 2020 09:03:56 -0700
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To: Peter Zijlstra <peterz@infradead.org>, Andrew Cooper <andrew.cooper3@citrix.com>
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On 6/23/20 8:52 AM, Peter Zijlstra wrote:
> Isn't current #MC unconditionally fatal from kernel? But yes, I was
> sorta aware people want that changed.

Not unconditionally.  copy_to_iter_mcsafe() is a good example of one
thing we _can_ handle.