Re: [PATCH 17/17] x86/boot: Drop CRC-32 checksum and the build tool that generates it

From: H. Peter Anvin
Date: Sat Aug 19 2023 - 22:40:13 EST




On 8/18/23 06:44, Ard Biesheuvel wrote:
The only remaining task carried out by the boot/tools/build.c build tool
is generating the CRC-32 checksum of the bzImage. This feature was added
in commit

7d6e737c8d2698b6 ("x86: add a crc32 checksum to the kernel image.")

without any motivation (or any commit log text, for that matter). This
checksum is not verified by any known bootloader, and given that

a) the checksum of the entire bzImage is reported by most tools (zlib,
rhash) as 0xffffffff and not 0x0 as documented,
b) the checksum is corrupted when the image is signed for secure boot,
which means that no distro ships x86 images with valid CRCs,

it seems quite unlikely that this checksum is being used, so let's just
drop it, along with the tool that generates it.


This one I have concerns with.

-hpa