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

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commit a006483b2f97af685f0e60f3a547c9ad4c9b9e94 upstream.

If the SME and SEV features are present via CPUID, but memory encryption
support is not enabled (MSR 0xC001_0010[23]), the feature flags are cleared
using clear_cpu_cap(). However, if get_cpu_cap() is later called, these
feature flags 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 flags is maintained.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org> # 4.16.x-
Link: https://lkml.kernel.org/r/226de90a703c3c0be5a49565047905ac4e94e8f3.1579125915.git.thomas.lendacky@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Tom Lendacky 2020-01-15 16:05:16 -06:00 committed by Greg Kroah-Hartman
parent f163ffa9df
commit 4e80eb337c
1 changed files with 2 additions and 2 deletions
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4
arch/x86/kernel/cpu/amd.c
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@ -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);
}
}