I want to generate System.map from vmlinuz,cause most of machines don't have the file System.map.In fact,vmlinuz are compressed to vmlinuz or bzImage.
It's any tool or script can do this?
I tried:
dd if=/boot/vmlinuz skip=`grep -a -b -o -m 1 -e $'\x1f\x8b\x08\x00' /boot/vmlinuz | cut -d: -f 1` bs=1 | zcat > /tmp/vmlinux It was failed:
zcat: stdin: not in gzip format 32769+0 records in 32768+0 records out To extract the uncompressed kernel from the kernel image, you can use the extract-vmlinux script from the scripts directory in the kernel tree (available at least in kernel version 3.5) (if you get an error like
mktemp: Cannot create temp file /tmp/vmlinux-XXX: Invalid argument
you need to replace $(mktemp /tmp/vmlinux-XXX) by $(mktemp /tmp/vmlinux-XXXXXX) in the script). The command is /path/to/kernel/tree/scripts/extract-vmlinux .
System.map file using the mksysmap script from the same subdirectory. The command here is NM=nm /path/to/kernel/tree/scripts/mksysmap vmlinux System.map.
As Abrixas2 wrote, you will need a kernel image with symbol information in order to create System.map files and a packed vmlinuz image is not likely to have symbols in it. I can, however, verify that the script in your original post works with '-e' replaced with '-P' and '$' dropped, i.e.,
$ dd if=vmlinuz-3.8.0-19-generic skip=`grep -a -b -o -m 1 -P '\x1f\x8b\x08\x00' vmlinuz-3.8.0-19-generic | cut -d: -f 1` bs=1 | zcat > /tmp/vmlinux gzip: stdin: decompression OK, trailing garbage ignored