Index: head/share/mk/src.opts.mk
===================================================================
--- head/share/mk/src.opts.mk
+++ head/share/mk/src.opts.mk
@@ -111,7 +111,6 @@
     GPIO \
     HAST \
     HTML \
-    HYPERV \
     ICONV \
     INET \
     INET6 \
@@ -371,6 +370,13 @@
 .else
 __DEFAULT_NO_OPTIONS+=CXGBETOOL
 __DEFAULT_NO_OPTIONS+=MLX5TOOL
+.endif
+
+# HyperV is currently x86-only
+.if ${__T} == "amd64" || ${__T} == "i386"
+__DEFAULT_YES_OPTIONS+=HYPERV
+.else
+__DEFAULT_NO_OPTIONS+=HYPERV
 .endif
 
 # NVME is only x86 and powerpc64
Index: head/tools/build/options/WITH_HYPERV
===================================================================
--- head/tools/build/options/WITH_HYPERV
+++ head/tools/build/options/WITH_HYPERV
@@ -0,0 +1,2 @@
+.\" $FreeBSD$
+Set to build or install HyperV utilities.