diff --git a/target/i386/kvm.c b/target/i386/kvm.c index 445e0e0b11..2d174f3a91 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -372,6 +372,13 @@ uint32_t kvm_arch_get_supported_cpuid(KVMState *s, uint32_t function, if (host_tsx_blacklisted()) { ret &= ~(CPUID_7_0_EBX_RTM | CPUID_7_0_EBX_HLE); } + } else if (function == 0x80000001 && reg == R_ECX) { + /* + * It's safe to enable TOPOEXT even if it's not returned by + * GET_SUPPORTED_CPUID. Unconditionally enabling TOPOEXT here allows + * us to keep CPU models including TOPOEXT runnable on older kernels. + */ + ret |= CPUID_EXT3_TOPOEXT; } else if (function == 0x80000001 && reg == R_EDX) { /* On Intel, kvm returns cpuid according to the Intel spec, * so add missing bits according to the AMD spec: