diff --git a/target/i386/cpu.c b/target/i386/cpu.c index 536d7d1520..c1ab86d63e 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -4730,6 +4730,9 @@ static void x86_cpu_reset(CPUState *s) env->pat = 0x0007040600070406ULL; env->msr_ia32_misc_enable = MSR_IA32_MISC_ENABLE_DEFAULT; + if (env->features[FEAT_1_ECX] & CPUID_EXT_MONITOR) { + env->msr_ia32_misc_enable |= MSR_IA32_MISC_ENABLE_MWAIT; + } memset(env->dr, 0, sizeof(env->dr)); env->dr[6] = DR6_FIXED_1; diff --git a/target/i386/cpu.h b/target/i386/cpu.h index fce6660bac..bd06523a53 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -387,6 +387,7 @@ typedef enum X86Seg { #define MSR_IA32_MISC_ENABLE 0x1a0 /* Indicates good rep/movs microcode on some processors: */ #define MSR_IA32_MISC_ENABLE_DEFAULT 1 +#define MSR_IA32_MISC_ENABLE_MWAIT (1ULL << 18) #define MSR_MTRRphysBase(reg) (0x200 + 2 * (reg)) #define MSR_MTRRphysMask(reg) (0x200 + 2 * (reg) + 1)