#define MSR_IA32_LASTINTFROMIP 0x000001dd
#define MSR_IA32_LASTINTTOIP 0x000001de
+/* DEBUGCTLMSR bits (others vary by model): */
+#define _DEBUGCTLMSR_LBR 0 /* last branch recording */
+#define _DEBUGCTLMSR_BTF 1 /* single-step on branches */
+
+#define DEBUGCTLMSR_LBR (1UL << _DEBUGCTLMSR_LBR)
+#define DEBUGCTLMSR_BTF (1UL << _DEBUGCTLMSR_BTF)
+
#define MSR_IA32_MC0_CTL 0x00000400
#define MSR_IA32_MC0_STATUS 0x00000401
#define MSR_IA32_MC0_ADDR 0x00000402