File 657365e7-check-amd-secure-guest.patch of Package libvirt.22291

commit 657365e74f489b70bfbf2eb014db63046c5e3888
Author: Paulo de Rezende Pinatti <ppinatti@linux.ibm.com>
Date:   Mon Jun 15 10:28:08 2020 +0200

    qemu: Check if AMD secure guest support is enabled
    
    Implement secure guest check for AMD SEV (Secure Encrypted
    Virtualization) in order to invalidate the qemu capabilities
    cache in case the availability of the feature changed.
    
    For AMD SEV the verification consists of:
     - checking if /sys/module/kvm_amd/parameters/sev contains the
       value '1': meaning SEV is enabled in the host kernel;
     - checking if /dev/sev exists
    
    Signed-off-by: Paulo de Rezende Pinatti <ppinatti@linux.ibm.com>
    Signed-off-by: Boris Fiuczynski <fiuczy@linux.ibm.com>
    Reviewed-by: Bjoern Walk <bwalk@linux.ibm.com>
    Reviewed-by: Erik Skultety <eskultet@redhat.com>

Index: libvirt-6.0.0/src/qemu/qemu_capabilities.c
===================================================================
--- libvirt-6.0.0.orig/src/qemu/qemu_capabilities.c
+++ libvirt-6.0.0/src/qemu/qemu_capabilities.c
@@ -4402,6 +4402,27 @@ virQEMUCapsKVMSupportsSecureGuestS390(vo
 
 
 /*
+ * Check whether AMD Secure Encrypted Virtualization (x86) is enabled
+ */
+static bool
+virQEMUCapsKVMSupportsSecureGuestAMD(void)
+{
+    g_autofree char *modValue = NULL;
+
+    if (virFileReadValueString(&modValue, "/sys/module/kvm_amd/parameters/sev") < 0)
+        return false;
+
+    if (modValue[0] != '1')
+        return false;
+
+    if (virFileExists(QEMU_DEV_SEV))
+        return true;
+
+    return false;
+}
+
+
+/*
  * Check whether the secure guest functionality is enabled.
  * See the specific architecture function for details on the verifications made.
  */
@@ -4412,6 +4433,10 @@ virQEMUCapsKVMSupportsSecureGuest(void)
 
     if (ARCH_IS_S390(arch))
         return virQEMUCapsKVMSupportsSecureGuestS390();
+
+    if (ARCH_IS_X86(arch))
+        return virQEMUCapsKVMSupportsSecureGuestAMD();
+
     return false;
 }