x86: when building image.iso, use isohybrid if it exists

When building image.iso (make isoimage), use the isohybrid tool if it
exists.  isohybrid is a script included with Syslinux 3.72 and higher,
which creates an image that can be booted either as a hard disk
(including removable, e.g. USB disk) or as a CD-ROM.

If isohybrid doesn't exist, then this has no effect.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile
index 7ee102f9c4f8c86b098c71168478e1a79443c97a..cceba1f46365aa30615314144fe9356decb596af 100644 (file)
--- a/arch/x86/boot/Makefile
+++ b/arch/x86/boot/Makefile
@@ -181,6 +181,7 @@ isoimage: $(BOOTIMAGE)
        mkisofs -J -r -o $(obj)/image.iso -b isolinux.bin -c boot.cat \
                -no-emul-boot -boot-load-size 4 -boot-info-table \
                $(obj)/isoimage
+       isohybrid $(obj)/image.iso 2>/dev/null || true
        rm -rf $(obj)/isoimage
 
 zlilo: $(BOOTIMAGE)