[PATCH v8 02/40] x86/sev: detect/setup SEV/SME features earlier in boot
From: Brijesh Singh <hidden>
Date: 2021-12-10 15:44:03
Also in:
kvm, linux-coco, linux-efi, lkml, platform-driver-x86
Subsystem:
the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
From: Michael Roth <redacted> 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 <redacted> Signed-off-by: Brijesh Singh <redacted> --- 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 3be9dd213dad..b01f64e8389b 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 d8b3ebd2bb85..99de8fd461e8 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
--
2.25.1