linux-kernel - Re: [PATCH v6 3/5] kvm: arm64: New memslot flag to indicate cacheable mapping

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Date: Tue, 27 May 2025 04:33:41 +0000
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Subject: Re: [PATCH v6 3/5] kvm: arm64: New memslot flag to indicate cacheable
 mapping

> I thought we agreed not to do this? Sean was strongly against it
> right?

> There is no easy way for VFIO to know to set it, and the kernel will
> not allow switching a cachable VMA to non-cachable anyhow.

> So all it does is make it harder to create a memslot.

Oliver had mentioned earlier that he would still prefer a memslot flag as
VMM should convey its intent through that flag:
https://lore.kernel.org/all/aAdKCGCuwlUeUXKY@linux.dev/

Oliver, could you please confirm if you are convinced with not having this
flag? Can we rely on MT_NORMAL in vma mapping to convey this?