[RFC PATCH] arm64: Expose physical/virtual address bits through cpuinfo

[Catalin Marinas]

On Thu, Mar 17, 2016 at 06:08:03PM +0800, Kefeng Wang wrote:
> AArch64 support six types Physical Address range, permitted values
> in ID_AA64MMFR0_EL1 are:
> 0000  32 bits, 4GB.
> 0001  36 bits, 64GB.
> 0010  40 bits, 1TB.
> 0011  42 bits, 4TB.
> 0100  44 bits, 16TB.
> 0101  48 bits, 256TB.
> All other values are reserved.
> 
> Meanwhile, AArch64 allows 36-bit, 39-bit, 42-bit, 47-bit and 48-bit
> virtual addresses.
> 
> Exposing the physical and virtual address bits to userspace through
> procfs like x86, then it is easy to check them from cpuinfo.

So, what does user space need such information for?

-- 
Catalin