From bcce829083339bf862d66df602cbb111943da8fb Mon Sep 17 00:00:00 2001 From: Michael Roth Date: Wed, 9 Feb 2022 12:10:02 -0600 Subject: [PATCH] x86/sev: Detect/setup SEV/SME features earlier in boot sme_enable() handles feature detection for both SEV and SME. Future patches will also use it for SEV-SNP feature detection/setup, which will need to be done immediately after the first #VC handler is set up. Move it now in preparation. Signed-off-by: Michael Roth Signed-off-by: Brijesh Singh Signed-off-by: Borislav Petkov Reviewed-by: Venu Busireddy Link: https://lore.kernel.org/r/20220307213356.2797205-9-brijesh.singh@amd.com --- arch/x86/kernel/head64.c | 3 --- arch/x86/kernel/head_64.S | 13 +++++++++++++ 2 files changed, 13 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 4f5ecbbaae77..cbc285ddc4ac 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -192,9 +192,6 @@ unsigned long __head __startup_64(unsigned long physaddr, if (load_delta & ~PMD_PAGE_MASK) for (;;); - /* Activate Secure Memory Encryption (SME) if supported and enabled */ - sme_enable(bp); - /* Include the SME encryption mask in the fixup value */ load_delta += sme_get_me_mask(); diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index b8e3019547a5..6bf340c91165 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -69,6 +69,19 @@ SYM_CODE_START_NOALIGN(startup_64) call startup_64_setup_env popq %rsi +#ifdef CONFIG_AMD_MEM_ENCRYPT + /* + * Activate SEV/SME memory encryption if supported/enabled. This needs to + * be done now, since this also includes setup of the SEV-SNP CPUID table, + * which needs to be done before any CPUID instructions are executed in + * subsequent code. + */ + movq %rsi, %rdi + pushq %rsi + call sme_enable + popq %rsi +#endif + /* Now switch to __KERNEL_CS so IRET works reliably */ pushq $__KERNEL_CS leaq .Lon_kernel_cs(%rip), %rax