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

H. Peter Anvin
2023-08-20T02:40:13Z

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