target/i386: add MDS-NO feature

Microarchitectural Data Sampling is a hardware vulnerability which allows
unprivileged speculative access to data which is available in various CPU
internal buffers.

Some Intel processors use the ARCH_CAP_MDS_NO bit in the
IA32_ARCH_CAPABILITIES
MSR to report that they are not vulnerable, make it available to guests.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20190516185320.28340-1-pbonzini@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
(cherry picked from commit 20140a82c67467f53814ca197403d5e1b561a5e5)
Signed-off-by: Oguz Bektas <o.bektas@proxmox.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index d6bb57d2108e26166cba6d9a55c0dff9fc559098..ee4b8b47e292abc615ef57bfeffd0988fca0b27d 100644 (file)
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -1183,7 +1183,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
         .type = MSR_FEATURE_WORD,
         .feat_names = {
             "rdctl-no", "ibrs-all", "rsba", "skip-l1dfl-vmentry",
-            "ssb-no", NULL, NULL, NULL,
+            "ssb-no", "mds-no", NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,