[PATCH v2 for-4.14] x86/msr: Disallow access to Processor Trace MSRs

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

We do not expose the feature to guests, so should disallow access to the
respective MSRs.  For simplicity, drop the entire block of MSRs, not just the
subset which have been specified thus far.

Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
CC: Jan Beulich <JBeulich@xxxxxxxx>
CC: Wei Liu <wl@xxxxxxx>
CC: Roger Pau Monné <roger.pau@xxxxxxxxxx>
CC: Paul Durrant <paul@xxxxxxx>
CC: Michał Leszczyński <michal.leszczynski@xxxxxxx>

Paul: For 4.14.  This needs backporting to older trees as well.

v2:
 * Drop the whole 0x560 => 0x58f block.
---
 xen/arch/x86/msr.c              | 2 ++
 xen/include/asm-x86/msr-index.h | 8 ++++++++
 2 files changed, 10 insertions(+)

diff --git a/xen/arch/x86/msr.c b/xen/arch/x86/msr.c
index 0bfb5839b2..22f921cc71 100644
--- a/xen/arch/x86/msr.c
+++ b/xen/arch/x86/msr.c
@@ -168,6 +168,7 @@ int guest_rdmsr(struct vcpu *v, uint32_t msr, uint64_t *val)
     case MSR_TSX_FORCE_ABORT:
     case MSR_TSX_CTRL:
     case MSR_MCU_OPT_CTRL:
+    case MSR_RTIT_OUTPUT_BASE ... MSR_RTIT_ADDR_B(7):
     case MSR_U_CET:
     case MSR_S_CET:
     case MSR_PL0_SSP ... MSR_INTERRUPT_SSP_TABLE:
@@ -329,6 +330,7 @@ int guest_wrmsr(struct vcpu *v, uint32_t msr, uint64_t val)
     case MSR_TSX_FORCE_ABORT:
     case MSR_TSX_CTRL:
     case MSR_MCU_OPT_CTRL:
+    case MSR_RTIT_OUTPUT_BASE ... MSR_RTIT_ADDR_B(7):
     case MSR_U_CET:
     case MSR_S_CET:
     case MSR_PL0_SSP ... MSR_INTERRUPT_SSP_TABLE:
diff --git a/xen/include/asm-x86/msr-index.h b/xen/include/asm-x86/msr-index.h
index b328a47ed8..0fe98af923 100644
--- a/xen/include/asm-x86/msr-index.h
+++ b/xen/include/asm-x86/msr-index.h
@@ -69,6 +69,14 @@
 #define MSR_MCU_OPT_CTRL                    0x00000123
 #define  MCU_OPT_CTRL_RNGDS_MITG_DIS        (_AC(1, ULL) <<  0)
 
+#define MSR_RTIT_OUTPUT_BASE                0x00000560
+#define MSR_RTIT_OUTPUT_MASK                0x00000561
+#define MSR_RTIT_CTL                        0x00000570
+#define MSR_RTIT_STATUS                     0x00000571
+#define MSR_RTIT_CR3_MATCH                  0x00000572
+#define MSR_RTIT_ADDR_A(n)                 (0x00000580 + (n) * 2)
+#define MSR_RTIT_ADDR_B(n)                 (0x00000581 + (n) * 2)
+
 #define MSR_U_CET                           0x000006a0
 #define MSR_S_CET                           0x000006a2
 #define  CET_SHSTK_EN                       (_AC(1, ULL) <<  0)
-- 
2.11.0