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Diffstat (limited to 'target-i386/kvm.c')
-rw-r--r--target-i386/kvm.c40
1 files changed, 33 insertions, 7 deletions
diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index 1212b507e7..23d6b869a3 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -532,6 +532,36 @@ static bool hyperv_enabled(X86CPU *cpu)
cpu->hyperv_stimer);
}
+static int kvm_arch_set_tsc_khz(CPUState *cs)
+{
+ X86CPU *cpu = X86_CPU(cs);
+ CPUX86State *env = &cpu->env;
+ int r;
+
+ if (!env->tsc_khz) {
+ return 0;
+ }
+
+ r = kvm_check_extension(cs->kvm_state, KVM_CAP_TSC_CONTROL) ?
+ kvm_vcpu_ioctl(cs, KVM_SET_TSC_KHZ, env->tsc_khz) :
+ -ENOTSUP;
+ if (r < 0) {
+ /* When KVM_SET_TSC_KHZ fails, it's an error only if the current
+ * TSC frequency doesn't match the one we want.
+ */
+ int cur_freq = kvm_check_extension(cs->kvm_state, KVM_CAP_GET_TSC_KHZ) ?
+ kvm_vcpu_ioctl(cs, KVM_GET_TSC_KHZ) :
+ -ENOTSUP;
+ if (cur_freq <= 0 || cur_freq != env->tsc_khz) {
+ error_report("warning: TSC frequency mismatch between "
+ "VM and host, and TSC scaling unavailable");
+ return r;
+ }
+ }
+
+ return 0;
+}
+
static Error *invtsc_mig_blocker;
#define KVM_MAX_CPUID_ENTRIES 100
@@ -859,13 +889,9 @@ int kvm_arch_init_vcpu(CPUState *cs)
return r;
}
- r = kvm_check_extension(cs->kvm_state, KVM_CAP_TSC_CONTROL);
- if (r && env->tsc_khz) {
- r = kvm_vcpu_ioctl(cs, KVM_SET_TSC_KHZ, env->tsc_khz);
- if (r < 0) {
- fprintf(stderr, "KVM_SET_TSC_KHZ failed\n");
- return r;
- }
+ r = kvm_arch_set_tsc_khz(cs);
+ if (r < 0) {
+ return r;
}
/* vcpu's TSC frequency is either specified by user, or following