[PATCH] x86/CPU/AMD: Ensure clearing of SME/SEV features is maintained

Tom Lendacky
2020-01-15T22:05:36Z

If the SME and SEV features are present via CPUID, but memory encryption
support is not enabled (MSR 0xC001_0010[23]), the features are cleared
using clear_cpu_cap(). However, if get_cpu_cap() is later called, these
features will be reset back to present, which is not desired.

Change from using clear_cpu_cap() to setup_clear_cpu_cap() so that the
clearing of the features is maintained.

Cc: <stable@vger.kernel.org> # 4.16.x-
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
arch/x86/kernel/cpu/amd.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 90f75e515876..62c30279be77 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -615,9 +615,9 @@ static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
return;

clear_all:
- clear_cpu_cap(c, X86_FEATURE_SME);
+ setup_clear_cpu_cap(X86_FEATURE_SME);
clear_sev:
- clear_cpu_cap(c, X86_FEATURE_SEV);
+ setup_clear_cpu_cap(X86_FEATURE_SEV);
}
}

--
2.17.1