[PATCH v3] arm64: mm: increase VA range of identity map

[catalin.marinas@arm.com (Catalin Marinas)]

On Thu, Feb 26, 2015 at 09:16:55AM +0000, Ard Biesheuvel wrote:
> The page size and the number of translation levels, and hence the supported
> virtual address range, are build-time configurables on arm64 whose optimal
> values are use case dependent. However, in the current implementation, if
> the system's RAM is located at a very high offset, the virtual address range
> needs to reflect that merely because the identity mapping, which is only used
> to enable or disable the MMU, requires the extended virtual range to map the
> physical memory at an equal virtual offset.
> 
> This patch relaxes that requirement, by increasing the number of translation
> levels for the identity mapping only, and only when actually needed, i.e.,
> when system RAM's offset is found to be out of reach at runtime.
> 
> Tested-by: Laura Abbott <lauraa@codeaurora.org>
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

The patch looks fine to me, though most likely for 4.1; in the meantime:

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>

Do you plan to look at the KVM aspect as well or we leave it with the
KVM maintainers?

-- 
Catalin