static inline bool kvm_mwait_in_guest(void)
{
- unsigned int eax, ebx, ecx, edx;
-
if (!cpu_has(&boot_cpu_data, X86_FEATURE_MWAIT))
return false;
/* All AMD CPUs have a working MWAIT implementation */
return true;
case X86_VENDOR_INTEL:
- /* Handle Intel below */
- break;
+ return !boot_cpu_has_bug(X86_BUG_MONITOR);
default:
return false;
}
-
- if (boot_cpu_has_bug(X86_BUG_MONITOR))
- return false;
-
- /*
- * Intel CPUs without CPUID5_ECX_INTERRUPT_BREAK are problematic as
- * they would allow guest to stop the CPU completely by disabling
- * interrupts then invoking MWAIT.
- */
- if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
- return false;
-
- cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &edx);
-
- if (!(ecx & CPUID5_ECX_INTERRUPT_BREAK))
- return false;
-
- return true;
}
#endif