error out if asked to extract a kver from image on non-x86v20

Version extraction only works on x86 (i686 and x86_64) kernels.

ref: https://bugs.archlinux.org/task/43256

2 files changed, 10 insertions, 3 deletions

diff --git a/man/mkinitcpio.8.txt b/man/mkinitcpio.8.txt
index 05d71c4..2f1bb84 100644
--- a/man/mkinitcpio.8.txt
+++ b/man/mkinitcpio.8.txt
@@ -49,8 +49,9 @@ Options
 
 *-k, \--kernel* 'kernelversion'::
 	Use 'kernelversion', instead of the current running kernel. This may be a
-	path to a kernel image, a specific kernel version or the special keyword
-	'none'. In the latter case, no kernel modules are added to the image.
+	path to a kernel image (only supported for x86-based architectures), a specific
+	kernel version or the special keyword 'none'. In the latter case, no kernel
+	modules are added to the image.
 
 *-L, \--listhooks*::
 	List all available hooks.
diff --git a/mkinitcpio b/mkinitcpio
index 713c4b4..3e550d3 100755
--- a/mkinitcpio
+++ b/mkinitcpio
@@ -85,7 +85,7 @@ cleanup() {
 }
 
 resolve_kernver() {
-    local kernel=$1 offset kver
+    local kernel=$1 arch= offset kver
 
     if [[ -z $kernel ]]; then
         uname -r
@@ -97,6 +97,12 @@ resolve_kernver() {
         return 0
     fi
 
+    arch=$(uname -m)
+    if [[ $arch != @(i686|x86_64) ]]; then
+        error "kernel version extraction from image not supported for \`%s' architecture" "$arch"
+        return 1
+    fi
+
     if [[ ! -e $kernel ]]; then
         error "specified kernel image does not exist: \`%s'" "$kernel"
         return 1