From 44f5e2649ee37f15607c516c8f9efc58aad708bb Mon Sep 17 00:00:00 2001
From: Eduardo Habkost <ehabkost@redhat.com>
Date: Wed, 9 Oct 2019 17:51:45 +0200
Subject: [PATCH 07/10] x86: define a new MSR based feature word --
 FEATURE_WORDS_ARCH_CAPABILITIES

RH-Author: Eduardo Habkost <ehabkost@redhat.com>
Message-id: <20191009175148.1361-8-ehabkost@redhat.com>
Patchwork-id: 91362
O-Subject: [RHEL-7.7.z qemu-kvm PATCH 07/10] x86: define a new MSR based feature word -- FEATURE_WORDS_ARCH_CAPABILITIES
Bugzilla: 1730606
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Acked-by: Bandan Das <bsd@redhat.com>
RH-Acked-by: Igor Mammedov <imammedo@redhat.com>

From: Robert Hoo <robert.hu@linux.intel.com>

Note RSBA is specially treated -- no matter host support it or not, qemu
pretends it is supported.

7.8 backport conflicts (plai):
	target/i386/cpu.c
	target/i386/cpu.h
	target/i386/kvm.c

7.7.z backport notes (ehabkost):
* Cherry picked from 7.8 tree with no conflicts

Signed-off-by: Robert Hoo <robert.hu@linux.intel.com>
Message-Id: <1539578845-37944-4-git-send-email-robert.hu@linux.intel.com>
[ehabkost: removed automatic enabling of RSBA]
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
(cherry picked from commit d86f963694df27f11b3681ffd225c9362de1b634)
Signed-off-by: Paul Lai <plai@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 target-i386/cpu.c | 23 +++++++++++++++++++++++
 target-i386/cpu.h |  8 ++++++++
 target-i386/kvm.c | 10 ++++++++++
 3 files changed, 41 insertions(+)

diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index 7fecd21..35381f0 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -199,6 +199,17 @@ static const char *cpuid_xsave_feature_name[] = {
     NULL, NULL, NULL, NULL,
 };
 
+static const char *cpuid_arch_capabilities_feature_name[] = {
+    "rdctl-no", "ibrs-all", "rsba", "skip-l1dfl-vmentry",
+    "ssb-no", NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL,
+};
+
 #define I486_FEATURES (CPUID_FP87 | CPUID_VME | CPUID_PSE)
 #define PENTIUM_FEATURES (I486_FEATURES | CPUID_DE | CPUID_TSC | \
           CPUID_MSR | CPUID_MCE | CPUID_CX8 | CPUID_MMX | CPUID_APIC)
@@ -375,6 +386,18 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
             .reg = R_EAX,
         },
     },
+    /*Below are MSR exposed features*/
+    [FEAT_ARCH_CAPABILITIES] = {
+        .type = MSR_FEATURE_WORD,
+        .feat_names = cpuid_arch_capabilities_feature_name,
+        .msr = {
+            .index = MSR_IA32_ARCH_CAPABILITIES,
+            .cpuid_dep = {
+                FEAT_7_0_EDX,
+                CPUID_7_0_EDX_ARCH_CAPABILITIES
+            }
+        },
+    },
 };
 
 typedef struct X86RegisterInfo32 {
diff --git a/target-i386/cpu.h b/target-i386/cpu.h
index ea5df77..1c62e63 100644
--- a/target-i386/cpu.h
+++ b/target-i386/cpu.h
@@ -415,6 +415,7 @@ typedef enum FeatureWord {
     FEAT_KVM,           /* CPUID[4000_0001].EAX (KVM_CPUID_FEATURES) */
     FEAT_SVM,           /* CPUID[8000_000A].EDX */
     FEAT_XSAVE,         /* CPUID[EAX=0xd,ECX=1].EAX */
+    FEAT_ARCH_CAPABILITIES,
     FEATURE_WORDS,
 } FeatureWord;
 
@@ -632,6 +633,13 @@ typedef uint32_t FeatureWordArray[FEATURE_WORDS];
 #define CPUID_MWAIT_IBE     (1U << 1) /* Interrupts can exit capability */
 #define CPUID_MWAIT_EMX     (1U << 0) /* enumeration supported */
 
+/* MSR Feature Bits */
+#define MSR_ARCH_CAP_RDCL_NO    (1U << 0)
+#define MSR_ARCH_CAP_IBRS_ALL   (1U << 1)
+#define MSR_ARCH_CAP_RSBA       (1U << 2)
+#define MSR_ARCH_CAP_SKIP_L1DFL_VMENTRY (1U << 3)
+#define MSR_ARCH_CAP_SSB_NO     (1U << 4)
+
 #ifndef HYPERV_SPINLOCK_NEVER_RETRY
 #define HYPERV_SPINLOCK_NEVER_RETRY             0xFFFFFFFF
 #endif
diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index 2b1d7da..180ae56 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -1325,6 +1325,16 @@ static int kvm_put_msrs(X86CPU *cpu, int level)
             kvm_msr_entry_set(&msrs[n++], MSR_IA32_TSC, env->tsc);
         }
     }
+    /* If host supports feature MSR, write down. */
+    if (kvm_feature_msrs) {
+        int i;
+        for (i = 0; i < kvm_feature_msrs->nmsrs; i++)
+            if (kvm_feature_msrs->indices[i] == MSR_IA32_ARCH_CAPABILITIES) {
+                kvm_msr_entry_set(&msrs[n++], MSR_IA32_ARCH_CAPABILITIES,
+                              env->features[FEAT_ARCH_CAPABILITIES]);
+                break;
+            }
+    }
     /*
      * The following MSRs have side effects on the guest or are too heavy
      * for normal writeback. Limit them to reset or full state updates.
-- 
1.8.3.1