x86-kvm-require-const-tsc-for-rt.patch

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 8838057da9c3542253fe543594e8b01c35a0806e..e961c1083db546d1920c3f91a2a3070dcb6ad5fc 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5766,6 +5766,13 @@ int kvm_arch_init(void *opaque)
                goto out;
        }
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+       if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
+               printk(KERN_ERR "RT requires X86_FEATURE_CONSTANT_TSC\n");
+               return -EOPNOTSUPP;
+       }
+#endif
+
        r = kvm_mmu_module_init();
        if (r)
                goto out_free_percpu;