Bug 520544

Summary:	ERROR: could not insert 'efivars': No such device
Product:	Gentoo Linux	Reporter:	Garry Filakhtov <filakhtov>
Component:	[OLD] Core system	Assignee:	Gentoo Xen Devs <xen>
Status:	UNCONFIRMED ---
Severity:	normal	CC:	filakhtov, floppym
Priority:	Normal
Version:	autobuilds
Hardware:	AMD64
OS:	Linux
Whiteboard:
Package list:		Runtime testing required:	---

Description Garry Filakhtov 2014-08-22 13:52:53 UTC

sys-kernel/gentoo-sources-3.14.14 was built with the following:
USE="symlink -build -deblob -experimental" ABI_X86="64"

app-emulation/xen-4.3.2-r5 was built with the following:
USE="efi -custom-cflags -debug -flask -xsm" ABI_X86="64"
CFLAGS=""

Booting the kernel directly works as it should.

If I'm trying to boot kernel from xen.efi I'm keep getting error while modprobing efivars.ko:

ERROR: could not insert 'efivars': No such device

The problem is that mdadm unable to assemble Intel firmware RAID without access to EFI variables and thus can't boot into real root, getting stuck in initramfs.

sys-fs/mdadm-3.2.6-r1 was built with the following:
USE="-static" ABI_X86="64"

Comment 1 Mike Gilbert gentoo-dev

2015-07-19 17:21:07 UTC

This seems like a missing module in your initramfs. What are you using to generate it?

Comment 2 Garry Filakhtov 2015-07-19 17:35:30 UTC

Using dracut to generate initramfs.

All related modules are included into initramfs, since system boots well without XEN hypervisor with (almost) the same initramfs.

On the other hand, under XEN, trying to load efivars I was getting: but on load it says: "could not insert 'efivars': No such device" (since some massive work was done recently on XEN system to support EFI/UEFI).

Btw, as far as I know it's might not be true anymore with latest XEN and kernel versions.

Unfortunately, I'm currently unable to prove or otherwise since my new hardware is incompatible with XEN hypervisor.