[PATCH 2/4] x86/vtx: Remove opencoded MSR_ARCH_CAPS check

From: Andrew Cooper <andrew.cooper3@citrix.com>
To: Xen-devel <xen-devel@lists.xenproject.org>
Cc: "Andrew Cooper" <andrew.cooper3@citrix.com>,
	"Jan Beulich" <JBeulich@suse.com>,
	"Roger Pau Monné" <roger.pau@citrix.com>, "Wei Liu" <wl@xen.org>,
	"Jun Nakajima" <jun.nakajima@intel.com>,
	"Kevin Tian" <kevin.tian@intel.com>
Subject: [PATCH 2/4] x86/vtx: Remove opencoded MSR_ARCH_CAPS check
Date: Tue, 16 May 2023 15:53:32 +0100	[thread overview]
Message-ID: <20230516145334.1271347-3-andrew.cooper3@citrix.com> (raw)
In-Reply-To: <20230516145334.1271347-1-andrew.cooper3@citrix.com>

MSR_ARCH_CAPS data is now included in featureset information.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
CC: Jan Beulich <JBeulich@suse.com>
CC: Roger Pau Monné <roger.pau@citrix.com>
CC: Wei Liu <wl@xen.org>
CC: Jun Nakajima <jun.nakajima@intel.com>
CC: Kevin Tian <kevin.tian@intel.com>
---
 xen/arch/x86/hvm/vmx/vmx.c            | 8 ++------
 xen/arch/x86/include/asm/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 096c69251d58..9dc16d0cc6b9 100644
--- a/xen/arch/x86/hvm/vmx/vmx.c
+++ b/xen/arch/x86/hvm/vmx/vmx.c
@@ -2849,8 +2849,6 @@ 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.
@@ -2858,10 +2856,8 @@ 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/arch/x86/include/asm/cpufeature.h b/xen/arch/x86/include/asm/cpufeature.h
index 4f827cc6ff91..8446f98625f7 100644
--- a/xen/arch/x86/include/asm/cpufeature.h
+++ b/xen/arch/x86/include/asm/cpufeature.h
@@ -183,6 +183,9 @@ static inline bool boot_cpu_has(unsigned int feat)
 #define cpu_has_avx_vnni_int8   boot_cpu_has(X86_FEATURE_AVX_VNNI_INT8)
 #define cpu_has_avx_ne_convert  boot_cpu_has(X86_FEATURE_AVX_NE_CONVERT)
 
+/* MSR_ARCH_CAPS 10A */
+#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)
-- 
2.30.2


