diff options
| author | Nikunj A Dadhania <nikunj@amd.com> | 2024-10-09 14:58:33 +0530 |
|---|---|---|
| committer | Borislav Petkov (AMD) <bp@alien8.de> | 2024-10-16 18:17:36 +0200 |
| commit | f75ff17fb48b1991d7a2822de5acc12bba240dc1 (patch) | |
| tree | 8958f7ed714b304c8ce26bee0d698e8167ae8481 | |
| parent | f3476bc77057db0adf90c0a141a3599dd11c56a0 (diff) | |
x86/sev: Handle failures from snp_init()
Address the ignored failures from snp_init() in sme_enable(). Add error
handling for scenarios where snp_init() fails to retrieve the SEV-SNP CC
blob or encounters issues while parsing the CC blob. Ensure that SNP guests
will error out early, preventing delayed error reporting or undefined
behavior.
Signed-off-by: Nikunj A Dadhania <nikunj@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20241009092850.197575-3-nikunj@amd.com
| -rw-r--r-- | arch/x86/mm/mem_encrypt_identity.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/arch/x86/mm/mem_encrypt_identity.c b/arch/x86/mm/mem_encrypt_identity.c index ac33b2263a43..e6c7686f443a 100644 --- a/arch/x86/mm/mem_encrypt_identity.c +++ b/arch/x86/mm/mem_encrypt_identity.c @@ -495,10 +495,10 @@ void __head sme_enable(struct boot_params *bp) unsigned int eax, ebx, ecx, edx; unsigned long feature_mask; unsigned long me_mask; - bool snp; + bool snp_en; u64 msr; - snp = snp_init(bp); + snp_en = snp_init(bp); /* Check for the SME/SEV support leaf */ eax = 0x80000000; @@ -531,8 +531,11 @@ void __head sme_enable(struct boot_params *bp) RIP_REL_REF(sev_status) = msr = __rdmsr(MSR_AMD64_SEV); feature_mask = (msr & MSR_AMD64_SEV_ENABLED) ? AMD_SEV_BIT : AMD_SME_BIT; - /* The SEV-SNP CC blob should never be present unless SEV-SNP is enabled. */ - if (snp && !(msr & MSR_AMD64_SEV_SNP_ENABLED)) + /* + * Any discrepancies between the presence of a CC blob and SNP + * enablement abort the guest. + */ + if (snp_en ^ !!(msr & MSR_AMD64_SEV_SNP_ENABLED)) snp_abort(); /* Check if memory encryption is enabled */ |