Boot error since 6.9: Initramfs unpacking failed: invalid magic at start of compressed archive

[Will Deacon]

On Mon, Jul 15, 2024 at 08:24:04AM +0200, Thorsten Leemhuis wrote:
> Hi, Thorsten here, the Linux kernel's regression tracker.
> 
> I noticed a report about a regression in bugzilla.kernel.org that a user
> bisected to the main ARM64 merge commit from the 6.9 cycle. So the real
> issue might be somewhere else, but some help would be appreciated. To
> quote from https://bugzilla.kernel.org/show_bug.cgi?id=219014 :
> 
> > Hi.
> > 
> > I'm marking as arm64 since git bisect identifies the first problematic commit as:
> >   6d75c6f40a03c97e1ecd683ae54e249abb9d922b
> > 
> > git bisect log is attached.
> > 
> > Any kernel tagged v6.9x and later fails to boot with the following error:
> > 
> > [    0.420154] Initramfs unpacking failed: invalid magic at start of compressed archive

^^^

My guess (based on times I've seen this sort of thing in the past) is
that the kernel binary grew in size and the broken bootloader is loading
the kernel over the initramfs instead of parsing the 'image_size' field
in the boot header.

Will