x86/mm: Include SEV for encryption memory attribute changes

The current code checks only for sme_active() when determining whether
to perform the encryption attribute change.  Include sev_active() in this
check so that memory attribute changes can occur under SME and SEV.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Tested-by: Borislav Petkov <bp@suse.de>
Cc: Laura Abbott <labbott@redhat.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: kvm@vger.kernel.org
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Link: https://lkml.kernel.org/r/20171020143059.3291-7-brijesh.singh@amd.com

arch/x86/mm/pageattr.c

@@ -1781,8 +1781,8 @@ static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc)
 	unsigned long start;
 	int ret;
 
-	/* Nothing to do if the SME is not active */
-	if (!sme_active())
+	/* Nothing to do if memory encryption is not active */
+	if (!mem_encrypt_active())
 		return 0;
 
 	/* Should not be working on unaligned addresses */