diff options
Diffstat (limited to 'arch/x86/kernel/cpu/hygon.c')
| -rw-r--r-- | arch/x86/kernel/cpu/hygon.c | 21 |
1 files changed, 3 insertions, 18 deletions
diff --git a/arch/x86/kernel/cpu/hygon.c b/arch/x86/kernel/cpu/hygon.c index 415621ddb8a2..4e28c1fc8749 100644 --- a/arch/x86/kernel/cpu/hygon.c +++ b/arch/x86/kernel/cpu/hygon.c @@ -330,12 +330,8 @@ static void init_hygon(struct cpuinfo_x86 *c) init_hygon_cacheinfo(c); if (cpu_has(c, X86_FEATURE_XMM2)) { - unsigned long long val; - int ret; - /* - * A serializing LFENCE has less overhead than MFENCE, so - * use it for execution serialization. On families which + * Use LFENCE for execution serialization. On families which * don't have that MSR, LFENCE is already serializing. * msr_set_bit() uses the safe accessors, too, even if the MSR * is not present. @@ -343,19 +339,8 @@ static void init_hygon(struct cpuinfo_x86 *c) msr_set_bit(MSR_F10H_DECFG, MSR_F10H_DECFG_LFENCE_SERIALIZE_BIT); - /* - * Verify that the MSR write was successful (could be running - * under a hypervisor) and only then assume that LFENCE is - * serializing. - */ - ret = rdmsrl_safe(MSR_F10H_DECFG, &val); - if (!ret && (val & MSR_F10H_DECFG_LFENCE_SERIALIZE)) { - /* A serializing LFENCE stops RDTSC speculation */ - set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC); - } else { - /* MFENCE stops RDTSC speculation */ - set_cpu_cap(c, X86_FEATURE_MFENCE_RDTSC); - } + /* A serializing LFENCE stops RDTSC speculation */ + set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC); } /* |