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From:   Oliver Upton <oliver.upton@linux.dev>
To:     Marc Zyngier <maz@kernel.org>
Cc:     Akihiko Odaki <akihiko.odaki@daynix.com>,
        linux-kernel@vger.kernel.org, kvmarm@lists.linux.dev,
        kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org,
        Mathieu Poirier <mathieu.poirier@linaro.org>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Alexandru Elisei <alexandru.elisei@arm.com>,
        James Morse <james.morse@arm.com>,
        Will Deacon <will@kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        asahi@lists.linux.dev, Alyssa Rosenzweig <alyssa@rosenzweig.io>,
        Sven Peter <sven@svenpeter.dev>,
        Hector Martin <marcan@marcan.st>
Subject: Re: [PATCH 0/3] KVM: arm64: Handle CCSIDR associativity mismatches
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References: <20221201104914.28944-1-akihiko.odaki@daynix.com>
 <867czbmlh1.wl-maz@kernel.org>
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On Thu, Dec 01, 2022 at 11:14:43PM +0000, Marc Zyngier wrote:
> On Thu, 01 Dec 2022 18:29:51 +0000,
> Oliver Upton <oliver.upton@linux.dev> wrote:
> > Could we extend your suggestion about accepting different topologies to
> > effectively tolerate _any_ topology provided by userspace? KVM can
> > default to the virtual topology, but a well-informed userspace could
> > still provide different values to its guest. No point in trying to
> > babyproofing the UAPI further, IMO.
> 
> I think this is *exactly* what I suggested. Any valid topology should
> be able to be restored, as we currently present the VM with any
> topology the host HW may have. This must be preserved.

Ah, I was narrowly reading into the conversation as it relates to the M2
implementation, my bad. SGTM :)

--
Thanks,
Oliver