Re: [PATCH 3/3] arm, arm64: KVM: handle potential incoherency of readonly memslots

Peter Maydell
2014-11-20T18:40:58Z

On 20 November 2014 18:35, Mario Smarduch <m.smarduch@samsung.com> wrote:
> I think beyond consistency, there should be no double mappings with
> conflicting attributes at any time or CPU state is undefined.

The situation is not so bleak as this. See section B2.9 "Mismatched
memory attributes" in the ARMv8 ARM ARM (DDI0487A.d), which lays
out in some detail what the results of mismatched attributes are
(generally, you lose ordering or coherency guarantees you might
have hoped to have). They're not pretty, but it's not as bad
as completely UNPREDICTABLE behaviour.

thanks
-- PMM