[xen stable-4.16] x86/vtx: Remove opencoded MSR_ARCH_CAPS check

[patchbot@xxxxxxx]

commit 6a007c521c2d3dcce56b7454d779c28ce720ac3d
Author:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
AuthorDate: Mon May 15 16:59:25 2023 +0100
Commit:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
CommitDate: Tue Aug 8 16:02:53 2023 +0100

    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@xxxxxxxxxx>
    Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
    (cherry picked from commit 8f6bc7f9b72eb7cf0c8c5ae5d80498a58ba0b7c3)
---
 xen/arch/x86/hvm/vmx/vmx.c       | 8 ++------
 xen/include/asm-x86/cpufeature.h | 3 +++
 2 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c
index a75bdde4ff..6c35812d05 100644
--- a/xen/arch/x86/hvm/vmx/vmx.c
+++ b/xen/arch/x86/hvm/vmx/vmx.c
@@ -2779,8 +2779,6 @@ static void __init ler_to_fixup_check(void);
  */
 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.
@@ -2788,10 +2786,8 @@ static bool __init has_if_pschange_mc(void)
     if ( cpu_has_hypervisor )
         return false;
 
-    if ( cpu_has_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;
 
     /*
diff --git a/xen/include/asm-x86/cpufeature.h b/xen/include/asm-x86/cpufeature.h
index 35fae5d649..ef4eedcaed 100644
--- a/xen/include/asm-x86/cpufeature.h
+++ b/xen/include/asm-x86/cpufeature.h
@@ -143,6 +143,9 @@
 #define cpu_has_avx_vnni        boot_cpu_has(X86_FEATURE_AVX_VNNI)
 #define cpu_has_avx512_bf16     boot_cpu_has(X86_FEATURE_AVX512_BF16)
 
+/* 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)
--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.16