[tip: x86/build] x86/build: Fix broken copy command in genimage.sh when making isoimage

[tip-bot2 for Nir Lichtman]

The following commit has been merged into the x86/build branch of tip:

Commit-ID:     e451630226bd09dc730eedb4e32cab1cc7155ae8
Gitweb:        https://git.kernel.org/tip/e451630226bd09dc730eedb4e32cab1cc7155ae8
Author:        Nir Lichtman <nir@xxxxxxxxxxxx>
AuthorDate:    Fri, 10 Jan 2025 12:05:00 
Committer:     Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Tue, 25 Feb 2025 21:13:33 +01:00

x86/build: Fix broken copy command in genimage.sh when making isoimage

Problem: Currently when running the "make isoimage" command there is an
error related to wrong parameters passed to the cp command:

  "cp: missing destination file operand after 'arch/x86/boot/isoimage/'"

This is caused because FDINITRDS is an empty array.

Solution: Check if FDINITRDS is empty before executing the "cp" command,
similar to how it is done in the case of hdimage.

Signed-off-by: Nir Lichtman <nir@xxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Ard Biesheuvel <ardb@xxxxxxxxxx>
Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Cc: Michal Marek <michal.lkml@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20250110120500.GA923218@xxxxxxxxxxxx
---
 arch/x86/boot/genimage.sh | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/x86/boot/genimage.sh b/arch/x86/boot/genimage.sh
index c9299ae..3882ead 100644
--- a/arch/x86/boot/genimage.sh
+++ b/arch/x86/boot/genimage.sh
@@ -22,6 +22,7 @@
 # This script requires:
 #   bash
 #   syslinux
+#   genisoimage
 #   mtools (for fdimage* and hdimage)
 #   edk2/OVMF (for hdimage)
 #
@@ -251,7 +252,9 @@ geniso() {
 	cp "$isolinux" "$ldlinux" "$tmp_dir"
 	cp "$FBZIMAGE" "$tmp_dir"/linux
 	echo default linux "$KCMDLINE" > "$tmp_dir"/isolinux.cfg
-	cp "${FDINITRDS[@]}" "$tmp_dir"/
+	if [ ${#FDINITRDS[@]} -gt 0 ]; then
+		cp "${FDINITRDS[@]}" "$tmp_dir"/
+	fi
 	genisoimage -J -r -appid 'LINUX_BOOT' -input-charset=utf-8 \
 		    -quiet -o "$FIMAGE" -b isolinux.bin \
 		    -c boot.cat -no-emul-boot -boot-load-size 4 \