The vmlinuz file contains other things besides the gzipped content, so you need to find out where the gzipped content starts. To do that, use: od -A d -t x1 vmlinuz | grep '1f 8b 08 00' What this does is to show you where in that file you can find the gzip header. The output looks like: 0024576 24 26 27 00 ae 21 16 00 1f 8b 08 00 7f 2f 6b 45 This means that at 0024576 (at leas..