Re: [PATCH] MdePkg/BaseLib AARCH64: terminate stack frame list on stack switch

[Leif Lindholm <leif.lindholm@linaro.org>]

On Fri, Sep 09, 2016 at 08:21:26AM +0100, Ard Biesheuvel wrote:
> When switching to the DXE phase stack, set the frame pointer to zero so
> that code walking the stack frame will not try to access stack frames\

Trailing '\'.

> belonging to the old stack.

Do you mean that code will check for zero and stop processing, or that
it will be accessing rubbish instead of parsing a valid-looking frame?

Either is an improvement, but if it is the latter I would prefer it
more explicitly stated.

You can fix up on commit:
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>

> Contributed-under: TianoCore Contribution Agreement 1.0
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> ---
>  MdePkg/Library/BaseLib/AArch64/SwitchStack.S | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/MdePkg/Library/BaseLib/AArch64/SwitchStack.S b/MdePkg/Library/BaseLib/AArch64/SwitchStack.S
> index 2bce9c998f4f..c3ac8d7e4dfe 100644
> --- a/MdePkg/Library/BaseLib/AArch64/SwitchStack.S
> +++ b/MdePkg/Library/BaseLib/AArch64/SwitchStack.S
> @@ -40,6 +40,7 @@ InternalSwitchStackAsm (
>    );
>  **/
>  ASM_PFX(InternalSwitchStackAsm):
> +    mov   x29, #0
>      mov   x30, x0
>      mov   sp, x3
>      mov   x0, x1
> -- 
> 2.7.4
>