From 9ab2237f1979f31de228b2a73b56925dbde938d1 Mon Sep 17 00:00:00 2001
From: Eduardo Habkost <ehabkost@redhat.com>
Date: Wed, 20 Nov 2019 13:49:11 -0300
Subject: [PATCH] i386: Add new versions of Skylake/Cascadelake/Icelake without
 TSX

One of the mitigation methods for TAA[1] is to disable TSX
support on the host system.  Linux added a mechanism to disable
TSX globally through the kernel command line, and many Linux
distributions now default to tsx=off.  This makes existing CPU
models that have HLE and RTM enabled not usable anymore.

Add new versions of all CPU models that have the HLE and RTM
features enabled, that can be used when TSX is disabled in the
host system.

References:

[1] TAA, TSX asynchronous Abort:
    https://software.intel.com/security-software-guidance/insights/deep-dive-intel-transactional-synchronization-extensions-intel-tsx-asynchronous-abort
    https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/tsx_async_abort.html

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 target/i386/cpu.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 9cd9adf788..37c023f2a9 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -2902,6 +2902,14 @@ static X86CPUDefinition builtin_x86_defs[] = {
                     { /* end of list */ }
                 }
             },
+            {
+                .version = 3,
+                .props = (PropValue[]) {
+                    { "hle", "off" },
+                    { "rtm", "off" },
+                    { /* end of list */ }
+                }
+            },
             { /* end of list */ }
         }
     },
@@ -3015,6 +3023,14 @@ static X86CPUDefinition builtin_x86_defs[] = {
                     { /* end of list */ }
                 }
             },
+            {
+                .version = 3,
+                .props = (PropValue[]) {
+                    { "hle", "off" },
+                    { "rtm", "off" },
+                    { /* end of list */ }
+                }
+            },
             { /* end of list */ }
         }
     },
@@ -3128,6 +3144,13 @@ static X86CPUDefinition builtin_x86_defs[] = {
                   { /* end of list */ }
               },
             },
+            { .version = 3,
+              .props = (PropValue[]) {
+                  { "hle", "off" },
+                  { "rtm", "off" },
+                  { /* end of list */ }
+              },
+            },
             { /* end of list */ }
         }
     },
@@ -3230,6 +3253,18 @@ static X86CPUDefinition builtin_x86_defs[] = {
         .features[FEAT_VMX_VMFUNC] = MSR_VMX_VMFUNC_EPT_SWITCHING,
         .xlevel = 0x80000008,
         .model_id = "Intel Core Processor (Icelake)",
+        .versions = (X86CPUVersionDefinition[]) {
+            { .version = 1 },
+            {
+                .version = 2,
+                .props = (PropValue[]) {
+                    { "hle", "off" },
+                    { "rtm", "off" },
+                    { /* end of list */ }
+                },
+            },
+            { /* end of list */ }
+        }
     },
     {
         .name = "Icelake-Server",
@@ -3334,6 +3369,18 @@ static X86CPUDefinition builtin_x86_defs[] = {
              VMX_SECONDARY_EXEC_ENABLE_VMFUNC | VMX_SECONDARY_EXEC_SHADOW_VMCS,
         .xlevel = 0x80000008,
         .model_id = "Intel Xeon Processor (Icelake)",
+        .versions = (X86CPUVersionDefinition[]) {
+            { .version = 1 },
+            {
+                .version = 2,
+                .props = (PropValue[]) {
+                    { "hle", "off" },
+                    { "rtm", "off" },
+                    { /* end of list */ }
+                },
+            },
+            { /* end of list */ }
+        }
     },
     {
         .name = "Denverton",