diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig
index c2cc9958087109f9e8e8aa749c0e0b8d693612cd..20b49729bed5e4788d5d7c107d09ef43dd455787 100644
--- a/arch/x86/xen/Kconfig
+++ b/arch/x86/xen/Kconfig
@@ -6,8 +6,8 @@ config XEN
 	bool "Xen guest support"
 	select PARAVIRT
 	select PARAVIRT_CLOCK
-	depends on X86_32
-	depends on X86_CMPXCHG && X86_TSC && X86_PAE && !(X86_VISWS || X86_VOYAGER)
+	depends on X86_64 || (X86_32 && X86_PAE && !(X86_VISWS || X86_VOYAGER))
+	depends on X86_CMPXCHG && X86_TSC
 	help
 	  This is the Linux Xen port.  Enabling this will allow the
 	  kernel to boot in a paravirtualized environment under the
@@ -15,10 +15,11 @@ config XEN
 
 config XEN_MAX_DOMAIN_MEMORY
        int "Maximum allowed size of a domain in gigabytes"
-       default 8
+       default 8 if X86_32
+       default 32 if X86_64
        depends on XEN
        help
          The pseudo-physical to machine address array is sized
          according to the maximum possible memory size of a Xen
          domain.  This array uses 1 page per gigabyte, so there's no
-         need to be too stingy here.
\ No newline at end of file
+         need to be too stingy here.