KVM is currently completely broken for the !CONFIG_SMP case.

drivers/kvm/kvm_main.c: In function ‘kvm_flush_remote_tlbs’:
drivers/kvm/kvm_main.c:220: error: implicit declaration of function ‘smp_call_function_mask’

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
---
I hope the KVM maintainer can come up with a better solution...

diff --git a/drivers/kvm/Kconfig b/drivers/kvm/Kconfig
index 8749fa4..e35fbc6 100644
--- a/drivers/kvm/Kconfig
+++ b/drivers/kvm/Kconfig
@@ -16,7 +16,7 @@ if VIRTUALIZATION
 
 config KVM
 	tristate "Kernel-based Virtual Machine (KVM) support"
-	depends on X86 && EXPERIMENTAL
+	depends on X86 && EXPERIMENTAL && SMP
 	select PREEMPT_NOTIFIERS
 	select ANON_INODES
 	---help---