Commit graph

5 commits

Author SHA1 Message Date
Jeremy Linton
b9f75396ec scripts: add zboot support to extract-vmlinux
Zboot compressed kernel images are used for arm64 kernels on various
distros.

extract-vmlinux fails with those kernels because the wrapped image is
another PE. While this could be a bit confusing, the tools primary
purpose of unwrapping and decompressing the contained kernel image
makes it the obvious place for this functionality.

Add a 'file' check in check_vmlinux() that detects a contained PE
image before trying readelf. Recent (FILES_39, Jun/2020) file
implementations output something like:

"Linux kernel ARM64 boot executable Image, little-endian, 4K pages"

Which is also a stronger statement than readelf provides so drop that
part of the comment. At the same time this means that kernel images
which don't appear to contain a compressed image will be returned
rather than reporting an error. Which matches the behavior for
existing ELF files.

The extracted PE image can then be inspected, or used as would any
other kernel PE.

Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2025-07-26 15:31:30 +09:00
Thomas Gleixner
4317cf95ca treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 378
Based on 1 normalized pattern(s):

  licensed under the gnu general public license version 2 gplv2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 5 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531081036.993848054@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:37:10 +02:00
Helge Deller
db139d71c4 extract-vmlinux: Check for uncompressed image as fallback
As on x86-64 and other architectures, the boot kernel on parisc (vmlinuz
and bzImage) contains a full compressed copy of the final kernel
executable (vmlinux.bin.gz), which one should be able to extract with
the extract-vmlinux script.

But on parisc extracting the kernel with extract-vmlinux fails.
Currently the script first checks if the given file is an ELF file
(which is true on parisc) and if so returns it.  Thus on parisc we
unexpectedly get back the vmlinuz boot file instead of the uncompressed
vmlinux image.

This patch fixes this issue by reverting the logic. It now first tries
to find a compression signature in the given file and if that fails it
checks the file itself as fallback.

Signed-off-by: Helge Deller <deller@gmx.de>
2018-10-17 08:18:01 +02:00
Adam Borowski
47a18a2dab scripts: teach extract-vmlinux about LZ4 and ZSTD
Note that the LZ4 signature is different than that of modern LZ4 as we
use the "legacy" format which suffers from some downsides like inability
to disable compression.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-07-08 09:32:32 +09:00
Corentin Chary
09d481270d scripts: add extract-vmlinux
This script can be used to extract vmlinux from a compressed
kernel image (bzImage, etc..). It's inspired from (a subset of)
extract-ikconfig.

It's something a lot of people have been looking for (mainly
people with xen < 4 that doesn't support bzImages at all).

Signed-off-by: Corentin Chary <corentincj@iksaif.net>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-08-31 16:12:17 +02:00