4.19-stable review patch. If anyone has any objections, please let me know.
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From: Sean Christopherson seanjc@google.com
[ Upstream commit 5df8ecfe3632d5879d1f154f7aa8de441b5d1c89 ]
Drop the explicit check on the extended CPUID level in cpu_has_svm(), the kernel's cached CPUID info will leave the entire SVM leaf unset if said leaf is not supported by hardware. Prior to using cached information, the check was needed to avoid false positives due to Intel's rather crazy CPUID behavior of returning the values of the maximum supported leaf if the specified leaf is unsupported.
Fixes: 682a8108872f ("x86/kvm/svm: Simplify cpu_has_svm()") Link: https://lore.kernel.org/r/20230721201859.2307736-13-seanjc@google.com Signed-off-by: Sean Christopherson seanjc@google.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/include/asm/virtext.h | 6 ------ 1 file changed, 6 deletions(-)
diff --git a/arch/x86/include/asm/virtext.h b/arch/x86/include/asm/virtext.h index 4699acd602af4..62810550024d3 100644 --- a/arch/x86/include/asm/virtext.h +++ b/arch/x86/include/asm/virtext.h @@ -89,12 +89,6 @@ static inline int cpu_has_svm(const char **msg) return 0; }
- if (boot_cpu_data.extended_cpuid_level < SVM_CPUID_FUNC) { - if (msg) - *msg = "can't execute cpuid_8000000a"; - return 0; - } - if (!boot_cpu_has(X86_FEATURE_SVM)) { if (msg) *msg = "svm not available";