Re: [PATCH 01/11] Initialize the mapping of KASan shadow memory

[Liuwenliang (Abbott Liu)]

On 16/11/17  22:41 Marc Zyngier [mailto:marc.zyngier@xxxxxxx] wrote:
>No, it doesn't. It cannot work, because Cortex-A9 predates the invention
>of the 64bit accessor. I suspect that you are testing stuff in QEMU,
>which is giving you a SW model that always supports LPAE. I suggest you
>test this code on *real* HW, and not only on QEMU.

I am sorry. My test is fault. I only defined TTBR0 as __ACCESS_CP15_64,
but I don't use the definition TTBR0 as __ACCESS_CP15_64. 

Now I use the definition TTBR0 as __ACCESS_CP15_64 on CPU supporting
LPAE(vexpress_a9), I find it doesn't work and report undefined instruction error
when execute "mrrc" instruction.

So, you are right that 64bit accessor of TTBR0 cannot work on LPAE.