Re: [PATCH v7 11/36] x86/mm: Add SME support for read_cr3_pa()

From: Andy Lutomirski
Date: Tue Jun 20 2017 - 12:18:22 EST


On Fri, Jun 16, 2017 at 11:51 AM, Tom Lendacky <thomas.lendacky@xxxxxxx> wrote:
> The cr3 register entry can contain the SME encryption mask that indicates
> the PGD is encrypted. The encryption mask should not be used when
> creating a virtual address from the cr3 register, so remove the SME
> encryption mask in the read_cr3_pa() function.
>
> During early boot SME will need to use a native version of read_cr3_pa(),
> so create native_read_cr3_pa().
>
> Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
> ---
> arch/x86/include/asm/processor-flags.h | 3 ++-
> arch/x86/include/asm/processor.h | 5 +++++
> 2 files changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/include/asm/processor-flags.h b/arch/x86/include/asm/processor-flags.h
> index 79aa2f9..cb6999c 100644
> --- a/arch/x86/include/asm/processor-flags.h
> +++ b/arch/x86/include/asm/processor-flags.h
> @@ -2,6 +2,7 @@
> #define _ASM_X86_PROCESSOR_FLAGS_H
>
> #include <uapi/asm/processor-flags.h>
> +#include <linux/mem_encrypt.h>
>
> #ifdef CONFIG_VM86
> #define X86_VM_MASK X86_EFLAGS_VM
> @@ -33,7 +34,7 @@
> */
> #ifdef CONFIG_X86_64
> /* Mask off the address space ID bits. */
> -#define CR3_ADDR_MASK 0x7FFFFFFFFFFFF000ull
> +#define CR3_ADDR_MASK __sme_clr(0x7FFFFFFFFFFFF000ull)

Can you update the comment one line above, too?