diff --git a/utils/update-kernel-headers.sh b/utils/update-kernel-headers.sh
index 8405be0ac..9a64dfb56 100755
--- a/utils/update-kernel-headers.sh
+++ b/utils/update-kernel-headers.sh
@@ -9,7 +9,7 @@ if [ $# != 1 ] ; then
 fi
 
 header_dir="$(dirname "$(realpath "$0")")/../include/linux"
-kernel_dir="$1"
+kernel_dir="$(realpath "$1")"
 
 # Bail out if the directory doesn't contain kernel sources
 line=$(head -3 "${kernel_dir}/Kbuild" 2>/dev/null | tail -1)