[xen staging-4.12] VT-x: extend LBR Broadwell errata coverage

[patchbot@xxxxxxx]

commit ad20170c7135b591f262719725f457c029fe34ad
Author:     Jan Beulich <jbeulich@xxxxxxxx>
AuthorDate: Wed Jun 24 17:11:44 2020 +0200
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Wed Jun 24 17:11:44 2020 +0200

    VT-x: extend LBR Broadwell errata coverage
    
    For lbr_tsx_fixup_check() simply name a few more specific erratum
    numbers.
    
    For bdf93_fixup_check(), however, more models are affected. Oddly enough
    despite being the same model and stepping, the erratum is listed for
    Xeon E3 but not its Core counterpart. Apply the workaround uniformly,
    and also for Xeon D, which only has the LBR-from one listed in its spec
    update.
    
    Seeing this broader applicability, rename anything BDF93-related to more
    generic names.
    
    Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
    Reviewed-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
    master commit: 724913de8ac8426d313a4645741d86c1169ae406
    master date: 2020-05-28 12:03:25 +0200
---
 xen/arch/x86/hvm/vmx/vmx.c | 52 ++++++++++++++++++++++++++++++----------------
 1 file changed, 34 insertions(+), 18 deletions(-)

diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c
index 69a9b502f6..7d29065d0b 100644
--- a/xen/arch/x86/hvm/vmx/vmx.c
+++ b/xen/arch/x86/hvm/vmx/vmx.c
@@ -2449,7 +2449,7 @@ static void pi_notification_interrupt(struct 
cpu_user_regs *regs)
 }
 
 static void __init lbr_tsx_fixup_check(void);
-static void __init bdf93_fixup_check(void);
+static void __init ler_to_fixup_check(void);
 
 /*
  * Calculate whether the CPU is vulnerable to Instruction Fetch page
@@ -2628,7 +2628,7 @@ const struct hvm_function_table * __init start_vmx(void)
     setup_vmcs_dump();
 
     lbr_tsx_fixup_check();
-    bdf93_fixup_check();
+    ler_to_fixup_check();
 
     return &vmx_function_table;
 }
@@ -2927,11 +2927,11 @@ enum
 
 #define LBR_MSRS_INSERTED      (1u << 0)
 #define LBR_FIXUP_TSX          (1u << 1)
-#define LBR_FIXUP_BDF93        (1u << 2)
-#define LBR_FIXUP_MASK         (LBR_FIXUP_TSX | LBR_FIXUP_BDF93)
+#define LBR_FIXUP_LER_TO       (1u << 2)
+#define LBR_FIXUP_MASK         (LBR_FIXUP_TSX | LBR_FIXUP_LER_TO)
 
 static bool __read_mostly lbr_tsx_fixup_needed;
-static bool __read_mostly bdf93_fixup_needed;
+static bool __read_mostly ler_to_fixup_needed;
 
 static void __init lbr_tsx_fixup_check(void)
 {
@@ -2939,7 +2939,7 @@ static void __init lbr_tsx_fixup_check(void)
     uint32_t lbr_format;
 
     /*
-     * HSM182, HSD172, HSE117, BDM127, BDD117, BDF85, BDE105:
+     * Haswell erratum HSM182 et al, Broadwell erratum BDM127 et al:
      *
      * On processors that do not support Intel Transactional Synchronization
      * Extensions (Intel TSX) (CPUID.07H.EBX bits 4 and 11 are both zero),
@@ -2963,8 +2963,11 @@ static void __init lbr_tsx_fixup_check(void)
     case 0x45: /* HSM182 - 4th gen Core */
     case 0x46: /* HSM182, HSD172 - 4th gen Core (GT3) */
     case 0x3d: /* BDM127 - 5th gen Core */
-    case 0x47: /* BDD117 - 5th gen Core (GT3) */
-    case 0x4f: /* BDF85  - Xeon E5-2600 v4 */
+    case 0x47: /* BDD117 - 5th gen Core (GT3)
+                  BDW117 - Xeon E3-1200 v4 */
+    case 0x4f: /* BDF85  - Xeon E5-2600 v4
+                  BDH75  - Core-i7 for LGA2011-v3 Socket
+                  BDX88  - Xeon E7-x800 v4 */
     case 0x56: /* BDE105 - Xeon D-1500 */
         break;
     default:
@@ -2985,18 +2988,31 @@ static void __init lbr_tsx_fixup_check(void)
         lbr_tsx_fixup_needed = true;
 }
 
-static void __init bdf93_fixup_check(void)
+static void __init ler_to_fixup_check(void)
 {
     /*
-     * Broadwell erratum BDF93:
+     * Broadwell erratum BDF93 et al:
      *
      * Reads from MSR_LER_TO_LIP (MSR 1DEH) may return values for bits[63:61]
      * that are not equal to bit[47].  Attempting to context switch this value
      * may cause a #GP.  Software should sign extend the MSR.
      */
-    if ( boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
-         boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model == 0x4f )
-        bdf93_fixup_needed = true;
+    if ( boot_cpu_data.x86_vendor != X86_VENDOR_INTEL ||
+         boot_cpu_data.x86 != 6 )
+        return;
+
+    switch ( boot_cpu_data.x86_model )
+    {
+    case 0x3d: /* BDM131 - 5th gen Core */
+    case 0x47: /* BDD??? - 5th gen Core (H-Processor line)
+                  BDW120 - Xeon E3-1200 v4 */
+    case 0x4f: /* BDF93  - Xeon E5-2600 v4
+                  BDH80  - Core-i7 for LGA2011-v3 Socket
+                  BDX93  - Xeon E7-x800 v4 */
+    case 0x56: /* BDE??? - Xeon D-1500 */
+        ler_to_fixup_needed = true;
+        break;
+    }
 }
 
 static int is_last_branch_msr(u32 ecx)
@@ -3357,8 +3373,8 @@ static int vmx_msr_write_intercept(unsigned int msr, 
uint64_t msr_content)
             v->arch.hvm.vmx.lbr_flags |= LBR_MSRS_INSERTED;
             if ( lbr_tsx_fixup_needed )
                 v->arch.hvm.vmx.lbr_flags |= LBR_FIXUP_TSX;
-            if ( bdf93_fixup_needed )
-                v->arch.hvm.vmx.lbr_flags |= LBR_FIXUP_BDF93;
+            if ( ler_to_fixup_needed )
+                v->arch.hvm.vmx.lbr_flags |= LBR_FIXUP_LER_TO;
         }
 
         __vmwrite(GUEST_IA32_DEBUGCTL, msr_content);
@@ -4418,7 +4434,7 @@ static void sign_extend_msr(struct vcpu *v, u32 msr, int 
type)
         entry->data = canonicalise_addr(entry->data);
 }
 
-static void bdf93_fixup(void)
+static void ler_to_fixup(void)
 {
     struct vcpu *curr = current;
 
@@ -4431,8 +4447,8 @@ static void lbr_fixup(void)
 
     if ( curr->arch.hvm.vmx.lbr_flags & LBR_FIXUP_TSX )
         lbr_tsx_fixup();
-    if ( curr->arch.hvm.vmx.lbr_flags & LBR_FIXUP_BDF93 )
-        bdf93_fixup();
+    if ( curr->arch.hvm.vmx.lbr_flags & LBR_FIXUP_LER_TO )
+        ler_to_fixup();
 }
 
 /* Returns false if the vmentry has to be restarted */
--
generated by git-patchbot for /home/xen/git/xen.git#staging-4.12