From ca0d1734b44a67ca0077c3f5714d901f7489559d Mon Sep 17 00:00:00 2001 From: bellard Date: Sat, 3 Sep 2005 16:25:14 +0000 Subject: [PATCH] SYSENTER fix for x86_64 CPUs git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1565 c046a42c-6fe2-441c-8c8c-71466251a162 --- kqemu.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/kqemu.c b/kqemu.c index 5b750ed..94792c0 100644 --- a/kqemu.c +++ b/kqemu.c @@ -119,13 +119,19 @@ static void kqemu_update_cpuid(CPUState *env) critical_features_mask = CPUID_CMOV | CPUID_CX8 | CPUID_FXSR | CPUID_MMX | CPUID_SSE | - CPUID_SSE2; + CPUID_SSE2 | CPUID_SEP; if (!is_cpuid_supported()) { features = 0; } else { cpuid(1, eax, ebx, ecx, edx); features = edx; } +#ifdef __x86_64__ + /* NOTE: on x86_64 CPUs, SYSENTER is not supported in + compatibility mode, so in order to have the best performances + it is better not to use it */ + features &= ~CPUID_SEP; +#endif env->cpuid_features = (env->cpuid_features & ~critical_features_mask) | (features & critical_features_mask); /* XXX: we could update more of the target CPUID state so that the -- 1.7.9.5