From 4d22c17c17d228b7f43e51293c7bb7dac87dea40 Mon Sep 17 00:00:00 2001 From: Xiaoyao Li Date: Fri, 19 Apr 2019 10:16:24 +0800 Subject: kvm: x86: refine kvm_get_arch_capabilities() 1. Using X86_FEATURE_ARCH_CAPABILITIES to enumerate the existence of MSR_IA32_ARCH_CAPABILITIES to avoid using rdmsrl_safe(). 2. Since kvm_get_arch_capabilities() is only used in this file, making it static. Signed-off-by: Xiaoyao Li Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 1 - arch/x86/kvm/x86.c | 8 ++++---- 2 files changed, 4 insertions(+), 5 deletions(-) (limited to 'arch') diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index d5457c7bb243..15e973d9b840 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1532,7 +1532,6 @@ int kvm_pv_send_ipi(struct kvm *kvm, unsigned long ipi_bitmap_low, unsigned long ipi_bitmap_high, u32 min, unsigned long icr, int op_64_bit); -u64 kvm_get_arch_capabilities(void); void kvm_define_shared_msr(unsigned index, u32 msr); int kvm_set_shared_msr(unsigned index, u64 val, u64 mask); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 5cb9ac9b61ab..8aa6b5a75e7a 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1212,11 +1212,12 @@ static u32 msr_based_features[] = { static unsigned int num_msr_based_features; -u64 kvm_get_arch_capabilities(void) +static u64 kvm_get_arch_capabilities(void) { - u64 data; + u64 data = 0; - rdmsrl_safe(MSR_IA32_ARCH_CAPABILITIES, &data); + if (boot_cpu_has(X86_FEATURE_ARCH_CAPABILITIES)) + rdmsrl(MSR_IA32_ARCH_CAPABILITIES, data); /* * If we're doing cache flushes (either "always" or "cond") @@ -1232,7 +1233,6 @@ u64 kvm_get_arch_capabilities(void) return data; } -EXPORT_SYMBOL_GPL(kvm_get_arch_capabilities); static int kvm_get_msr_feature(struct kvm_msr_entry *msr) { -- cgit v1.2.3