File xsa435-0-40.patch of Package xen.31135

From 8f6bc7f9b72eb7cf0c8c5ae5d80498a58ba0b7c3 Mon Sep 17 00:00:00 2001
From: Andrew Cooper <andrew.cooper3@citrix.com>
Date: Mon, 15 May 2023 16:59:25 +0100
Subject: x86/vtx: Remove opencoded MSR_ARCH_CAPS check

MSR_ARCH_CAPS data is now included in featureset information.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>

--- a/xen/arch/x86/hvm/vmx/vmx.c
+++ b/xen/arch/x86/hvm/vmx/vmx.c
@@ -2383,8 +2383,6 @@ static void __init ler_to_fixup_check(vo
  */
 static bool __init has_if_pschange_mc(void)
 {
-    uint64_t caps = 0;
-
     /*
      * If we are virtualised, there is nothing we can do.  Our EPT tables are
      * shadowed by our hypervisor, and not walked by hardware.
@@ -2392,10 +2390,8 @@ static bool __init has_if_pschange_mc(vo
     if ( cpu_has_hypervisor )
         return false;
 
-    if ( boot_cpu_has(X86_FEATURE_ARCH_CAPS) )
-        rdmsrl(MSR_ARCH_CAPABILITIES, caps);
-
-    if ( caps & ARCH_CAPS_IF_PSCHANGE_MC_NO )
+    /* Hardware reports itself as fixed. */
+    if ( cpu_has_if_pschange_mc_no )
         return false;
 
     /*
--- a/xen/include/asm-x86/cpufeature.h
+++ b/xen/include/asm-x86/cpufeature.h
@@ -136,6 +136,9 @@
 #define cpu_has_tsx_force_abort boot_cpu_has(X86_FEATURE_TSX_FORCE_ABORT)
 #define cpu_has_arch_caps       boot_cpu_has(X86_FEATURE_ARCH_CAPS)
 
+/* MSR_ARCH_CAPS */
+#define cpu_has_if_pschange_mc_no boot_cpu_has(X86_FEATURE_IF_PSCHANGE_MC_NO)
+
 /* Synthesized. */
 #define cpu_has_arch_perfmon    boot_cpu_has(X86_FEATURE_ARCH_PERFMON)
 #define cpu_has_cpuid_faulting  boot_cpu_has(X86_FEATURE_CPUID_FAULTING)