diff options
| author | Tom Lendacky <thomas.lendacky@amd.com> | 2024-12-02 14:50:48 -0600 |
|---|---|---|
| committer | Borislav Petkov (AMD) <bp@alien8.de> | 2024-12-14 10:55:28 +0100 |
| commit | 4972808d6f4a2b4c10eb3035d769f2e1a003da2f (patch) | |
| tree | 48c1022ea3cf87744e967a1519c0f7b8ed594c31 /arch/x86/kernel/cpu | |
| parent | 0cbc0258415814c86eb6db50237ae3d90fbf3b3d (diff) | |
x86/sev: Require the RMPREAD instruction after Zen4
Limit usage of the non-architectural RMP format to Zen3/Zen4 processors.
The RMPREAD instruction, with architectural defined output, is available
and should be used for RMP access beyond Zen4.
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Nikunj A Dadhania <nikunj@amd.com>
Reviewed-by: Neeraj Upadhyay <Neeraj.Upadhyay@amd.com>
Reviewed-by: Ashish Kalra <ashish.kalra@amd.com>
Link: https://lore.kernel.org/r/5be0093e091778a151266ea853352f62f838eb99.1733172653.git.thomas.lendacky@amd.com
Diffstat (limited to 'arch/x86/kernel/cpu')
| -rw-r--r-- | arch/x86/kernel/cpu/amd.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index 79d2e17f6582..b9592c60166e 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -355,10 +355,15 @@ static void bsp_determine_snp(struct cpuinfo_x86 *c) /* * RMP table entry format is not architectural and is defined by the * per-processor PPR. Restrict SNP support on the known CPU models - * for which the RMP table entry format is currently defined for. + * for which the RMP table entry format is currently defined or for + * processors which support the architecturally defined RMPREAD + * instruction. */ if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && - c->x86 >= 0x19 && snp_probe_rmptable_info()) { + (cpu_feature_enabled(X86_FEATURE_ZEN3) || + cpu_feature_enabled(X86_FEATURE_ZEN4) || + cpu_feature_enabled(X86_FEATURE_RMPREAD)) && + snp_probe_rmptable_info()) { cc_platform_set(CC_ATTR_HOST_SEV_SNP); } else { setup_clear_cpu_cap(X86_FEATURE_SEV_SNP); |