On 09/05/2016 10:22 AM, Borislav Petkov wrote: > On Mon, Aug 22, 2016 at 05:36:46PM -0500, Tom Lendacky wrote: >> Adding general kernel support for memory encryption includes: >> - Modify and create some page table macros to include the Secure Memory >> Encryption (SME) memory encryption mask >> - Update kernel boot support to call an SME routine that checks for and >> sets the SME capability (the SME routine will grow later and for now >> is just a stub routine) >> - Update kernel boot support to call an SME routine that encrypts the >> kernel (the SME routine will grow later and for now is just a stub >> routine) >> - Provide an SME initialization routine to update the protection map with >> the memory encryption mask so that it is used by default >> >> Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx> > > ... > >> diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S >> index c98a559..30f7715 100644 >> --- a/arch/x86/kernel/head_64.S >> +++ b/arch/x86/kernel/head_64.S >> @@ -95,6 +95,13 @@ startup_64: >> jnz bad_address >> >> /* >> + * Enable memory encryption (if available). Add the memory encryption >> + * mask to %rbp to include it in the the page table fixup. >> + */ >> + call sme_enable >> + addq sme_me_mask(%rip), %rbp >> + >> + /* >> * Fixup the physical addresses in the page table >> */ >> addq %rbp, early_level4_pgt + (L4_START_KERNEL*8)(%rip) >> @@ -116,7 +123,8 @@ startup_64: >> movq %rdi, %rax >> shrq $PGDIR_SHIFT, %rax >> >> - leaq (4096 + _KERNPG_TABLE)(%rbx), %rdx >> + leaq (4096 + __KERNPG_TABLE)(%rbx), %rdx >> + addq sme_me_mask(%rip), %rdx /* Apply mem encryption mask */ > > Please add comments over the line and not at the side... Ok, will do. Thanks, Tom > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>