set `ptgen -o "$OUTPUT" -h $head -s $sect -p ${KERNELSIZE}m -p ${ROOTFSSIZE}m`
KERNELOFFSET="$(($1 / 512))"
-ROOTFSOFFSET="$(($2 / 512))"
-ROOTFSSIZE="$(( ($3 - $2) / 512))"
+KERNELSIZE="$(($2 / 512))"
+ROOTFSOFFSET="$(($3 / 512))"
+ROOTFSSIZE="$(($4 / 512))"
-BLOCKS="$((($ROOTFSOFFSET - $KERNELOFFSET) / 2 - 1))"
+BLOCKS="$((($KERNELSIZE / 2) - 1))"
genext2fs -d "$KERNELDIR" -b "$BLOCKS" "$OUTPUT.kernel"
dd if="$OUTPUT.kernel" of="$OUTPUT" bs=512 seek="$KERNELOFFSET" conv=notrunc