Re: Can't boot kernel 6.17.4+ via rEFInd

[Nathan Chancellor <nathan@kernel.org>]

Hi Eugene,

On Wed, Oct 29, 2025 at 09:07:20PM +0100, Eugene Shalygin wrote:
> On Tue, 28 Oct 2025 at 18:45, Nathan Chancellor <nathan@kernel.org> wrote:
> > > Replacing CONFIG_KERNEL_ZSTD with  CONFIG_KERNEL_GZIP made the kernel
> > > bootable. What does that mean?
> >
> > Hmmmm, I am not sure... That seems rather odd within the context of the
> > flagged change.
> 
> Huh! The fourth of my machines with the similar config (also fully
> updated ~amd64 Gentoo) with rEFind boots kernel 6.17.5 with
> CONFIG_KERNEL_ZSTD enabled.
> 
> > Could you post the output of 'readelf -S vmlinux vmlinux.unstripped'
> > from the broken and good builds?
> 
> Attached.

Unfortunately, nothing appears to be out of the ordinary there... Only
.modinfo gets removed from the vmlinux.unstripped to vmlinux stage.

> > Does rEFInd have any sort of additional
> > debugging to see why/what it is complaining about not being able to
> > find?
> 
> No, unfortunately. However, I was unable to find the first part of the
> error message ("Not Found") in the rEFInd sources.

I am guessing the "Not Found" is EFI_NOT_FOUND, so I think this is
coming from StartEFIImage() in refind/launch_efi.c:

  https://sourceforge.net/p/refind/code/ci/253abe5c4af58d044912517daa567c4440612c46/tree/refind/launch_efi.c#l290

I am not sure where the LoadImage call comes from (the firmware?) so I
don't really know why that call would fail... Has CONFIG_KERNEL_ZSTD
always worked in this configuration? Presumably since you are not seeing
"Invalid loader file", you are going into the

  if ((LoaderType == LOADER_TYPE_EFI) || (LoaderType == LOADER_TYPE_GZIP)) {

branch there. I am at a bit of a loss here. Ard, could you see any
obvious reason from an EFI perspective why

  3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped")

would cause issues with booting via rEFInd? You can see Eugene's
original report at

  https://lore.kernel.org/CAB95QARfqSUNJCCgyPcTPu0-hk10e-sOVVMrnpKd6OdV_PHrGA@mail.gmail.com/

and subsequent replies in case they are relevant.

Cheers,
Nathan