EDAC/mce_amd: Do not load edac_mce_amd module on guests

Hypervisors likely do not expose the SMCA feature to the guest and
loading this module leads to false warnings. This module should not be
loaded in guests to begin with, but people tend to do so, especially
when testing kernels in VMs. And then they complain about those false
warnings.

Do the practical thing and do not load this module when running as a
guest to avoid all that complaining.

 [ bp: Rewrite commit message. ]

Suggested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Yazen Ghannam <yazen.ghannam@amd.com>
Tested-by: Kim Phillips <kim.phillips@amd.com>
Link: https://lkml.kernel.org/r/20210628172740.245689-1-Smita.KoralahalliChannabasappa@amd.com

drivers/edac/mce_amd.c

@@ -1246,6 +1246,9 @@ static int __init mce_amd_init(void)
 	    c->x86_vendor != X86_VENDOR_HYGON)
 		return -ENODEV;
 
+	if (cpu_feature_enabled(X86_FEATURE_HYPERVISOR))
+		return -ENODEV;
+
 	if (boot_cpu_has(X86_FEATURE_SMCA)) {
 		xec_mask = 0x3f;
 		goto out;