Re: [PATCH v5 33/75] x86/head/64: Switch to initial stack earlier

From: Kees Cook
Date: Fri Jul 24 2020 - 13:43:14 EST


On Fri, Jul 24, 2020 at 06:02:54PM +0200, Joerg Roedel wrote:
> From: Joerg Roedel <jroedel@xxxxxxx>
>
> Make sure there is a stack once the kernel runs from virual addresses.
> At this stage any secondary CPU which boots will have lost its stack
> because the kernel switched to a new page-table which does not map the
> real-mode stack anymore.
>
> This is needed for handling early #VC exceptions caused by instructions
> like CPUID.
>
> Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

--
Kees Cook