Re: [Qemu-arm] [Qemu-devel] [PATCHv2 1/3] target/arm: fix AArch64 virtual address space size

[Richard Henderson]

On 1/25/19 10:52 PM, Rémi Denis-Courmont wrote:
> From: Remi Denis-Courmont <address@hidden>
> 
> Since QEMU does not support the ARMv8.2-LVA, Large Virtual Address,
> extension (yet), the VA address space is 48-bits plus a sign bit. User
> mode can only handle the positive half of the address space, so that
> makes a limit of 48 bits.
> 
> (With LVA, it would be 53 and 52 bits respectively.)
> 
> The incorrectly large address space conflicts with PAuth instructions,
> which bits 48-54 and 56-63 for the pointer authentication code. This
> also conflicts with (as yet unsupported by QEMU) data tagging and with
> the ARMv8.5-MTE extension.
> 
> Signed-off-by: Remi Denis-Courmont <address@hidden>
> ---
>  target/arm/cpu.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Reviewed-by: Richard Henderson <address@hidden>


r~