On Mon, Aug 24, 2020 at 10:54:26AM +0200, Joerg Roedel wrote:
> diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
> index 2b2e91627221..800053219054 100644
> --- a/arch/x86/kernel/head_64.S
> +++ b/arch/x86/kernel/head_64.S
> @@ -78,6 +78,14 @@ SYM_CODE_START_NOALIGN(startup_64)
> call startup_64_setup_env
> popq %rsi
>
> + /*
> + * Setup %gs here already to make stack-protector work - it needs to be
> + * setup again after the switch to kernel addresses. The address read
> + * from initial_gs is a kernel address, so it needs to be adjusted first
> + * for the identity mapping.
> + */
> + movl $MSR_GS_BASE,%ecx
I'm confused: is this missing those three lines:
movl initial_gs(%rip),%eax
movl initial_gs+4(%rip),%edx
wrmsr
as it is done in secondary_startup_64 ?
Or why would you otherwise put 0xc0000101 in %ecx and not do anything
with it...
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
