I have the exact same issue with a custom built kernel (didn't try any rawhide stuff). In my case, it was a plain 4.3 kernel.

I'll try tonight with kernels coming from rawhide just to confirm.

Ok so I tried with 4.4.0-0.rc0.git8.1.fc24 and it works.

I'm compiling a custom kernel as we speak to test.

Doesn't work with 4.3.0-12036-g63f4f7e....

Maybe it's a kernel bug more than a grub thing.

Works with 4.4.0-0.rc1.git1.1.fc24.x86_64

Still doesn't with my own 4.4.0-rc1-00144-gb4ba1f0

It's definitely a grub bug but I haven't found anything related upstream.

I'm encountering this on a ~year old laptop with a 4.2.6-based kernel build as well.

The mystery remains then.

I'm typing this from a year old Thinkpad laptop on a homebuilt 4.3.0 kernel and grub2 works...

The whole boot + EFI + signed binaries thing makes it hard to debug.

I'll be looking at how to do that.

I'm having the same problem with a custom 4.2.6 kernel on a Lenovo Yoga 900 with a core i7 Skylake chip.  Same custom kernel on this ~4 year old Dell I'm typing from works just fine.  Does it by chance have anything to do with the kernel being compiled on the Dell and then installed on the Lenovo?  One of the issues I was patching was the wifi being disabled on the Lenovo, so downloading and building the custom kernel on that machine wasn't the best option (no ethernet port for backup).  That being said, if I need to, I can try to transfer everything I need from the Dell to the Lenovo via USB stick and build it there.  Does it sound like that might fix the problem?

Can anybody seeing this problem attach the grub2.cfg and grubenv files in use while they see it?

Hi Peter, here are mines...

Created attachment 1100992 [details]
mathieu's grubenv

Created attachment 1100993 [details]
mathieu's grub2.cfg

So in my case, official Fedora kernel builds boot fine, it's only a local build that fails, even with 100% identical config. And the failure goes away when I disable secure boot in efi. My system's /etc/grub2.cfg points to a non-existent file, but /etc/grub2-efi.cfg is valid. Attaching shortly.

Created attachment 1101092 [details]
grub2-efi.cfg from MSI GS60 laptop

Created attachment 1101094 [details]
grubenv from MSI GS60 laptop

My problem is identical to Jarod. Only locally built kernels fail. Haven't tried the secure boot thing but I shall and will report.

FYI I attached grub2-efi.cfg.

Turns out I'm an idiot, and hadn't enrolled my local signing key, so the kernel isn't expected to boot with secure boot enabled anyway, but it seems this isn't the expected error message...

Most likely I'm idiot too. Jarod, I've been looking for instructions how to do that? Are there any online?

(In reply to Mathieu Chouquet-Stringer from comment #17)
> Most likely I'm idiot too. Jarod, I've been looking for instructions how to
> do that? Are there any online?

You probably don't want to do that.  Enrolling the test certificate means that any kernel signed with that test cert will boot.  Since we ship the test cert, anyone in the world can create such a kernel.  That pretty much negates the benefit of Secure Boot.  (If you're creating your own signing cert and using that for local builds and only you have access to it, then it might be worthwhile.  Most people aren't doing that though.)

Instead, you might want to use mokutil to temporarily disable the validation steps.  mokutil --disable-validation as root.

I ended up creating my own cert and signed my own kernel. It boots fine.

So yes, in the end it's clearly just a secure boot issue and as you mentioned, grub shouldn't fail with a "double free" when the kernel isn't (properly) signed.

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