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Date: Wed, 31 Mar 2021 13:47:12 +1100
From: Paul Mackerras <paulus@ozlabs.org>
To: Nicholas Piggin <npiggin@gmail.com>
Subject: Re: [PATCH v4 01/46] KVM: PPC: Book3S HV: Nested move LPCR
 sanitising to sanitise_hv_regs
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 <20210323010305.1045293-2-npiggin@gmail.com>
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On Tue, Mar 23, 2021 at 11:02:20AM +1000, Nicholas Piggin wrote:
> This will get a bit more complicated in future patches. Move it
> into the helper function.

This does change L1-visible behaviour, because now the L1 hypervisor
can see the LPCR bits that L0 is using, whereas previously it couldn't
(and that was deliberate).  I can't point to a specific scenario where
that is a real problem, but nevertheless it worries me.  And the
behaviour change should have been mentioned in the commit message at
least.

Paul.