[PATCH 1/7] hyperv: Detect Nested virtualization support for SVM

[Vineeth Pillai <viremana@linux.microsoft.com>]

Detect nested features exposed by Hyper-V if SVM is enabled.

Signed-off-by: Vineeth Pillai <viremana@linux.microsoft.com>
---
 arch/x86/kernel/cpu/mshyperv.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 3546d3e21787..4d364acfe95d 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -325,9 +325,17 @@ static void __init ms_hyperv_init_platform(void)
 			ms_hyperv.isolation_config_a, ms_hyperv.isolation_config_b);
 	}
 
-	if (ms_hyperv.hints & HV_X64_ENLIGHTENED_VMCS_RECOMMENDED) {
+	/*
+	 * AMD does not need enlightened VMCS as VMCB is already a
+	 * datastructure in memory. We need to get the nested
+	 * features if SVM is enabled.
+	 */
+	if (boot_cpu_has(X86_FEATURE_SVM) ||
+	    ms_hyperv.hints & HV_X64_ENLIGHTENED_VMCS_RECOMMENDED) {
 		ms_hyperv.nested_features =
 			cpuid_eax(HYPERV_CPUID_NESTED_FEATURES);
+		pr_info("Hyper-V nested_features: 0x%x\n",
+			ms_hyperv.nested_features);
 	}
 
 	/*
-- 
2.25.1