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

[Ard Biesheuvel]

On 26 February 2015 at 11:27, Catalin Marinas <catalin.marinas at arm.com> wrote:
> 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 at codeaurora.org>
>> Signed-off-by: Ard Biesheuvel <ard.biesheuvel at linaro.org>
>
> The patch looks fine to me, though most likely for 4.1; in the meantime:
>
> Reviewed-by: Catalin Marinas <catalin.marinas at arm.com>
>

Thanks. Either 4.0 or 4.1 is fine by me.

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

I am looking into that atm.

-- 
Ard.