os-prober is intended to help the user locate other OS's and grub-mkconfig calls it when it runs (the level 30 script). However, it WILL FAIL to find a Windows EFI partition because it looks for output from udevadm that will never be produced. Specifically: 05efi in /usr/lib/os-probes/mounted excepts udevadm info -q property -n <part> to return ID_PART_ENTRY_TYPE and ID_PART_ENTRY_SCHEME Actual output of udevadm info -q property -n /dev/sda1 (my EFI partition): DEVPATH=/devices/pci0000:00/0000:00:1f.2/ata1/host0/target0:0:0/0:0:0:0/block/sda/sda1 DEVNAME=/dev/sda1 DEVTYPE=partition PARTN=1 PARTNAME=EFI system partition MAJOR=8 MINOR=1 SUBSYSTEM=block Result: ID_PART_ENTRY_TYPE and ID_PART_TYPE_SCHEME are both not present, thus 05efi does not recognize partition as EFI partition From log (with some debugging output added by me to help trace the error): Dec 23 15:21:11 livecd 05efi[20142]: debug: calling udevadm info -q property -n "/dev/sda1" Dec 23 15:21:11 livecd 05efi[20147]: debug: /dev/sda1 partition scheme is Dec 23 15:21:11 livecd 05efi[20148]: debug: /dev/sda1 partition type is
Does this mean this package is totally unusable right now?
I'd personally go so far as to mask it in the portage tree. At least until someone can fix it. I'd almost be willing to do it myself except I'm not quite in a position to do so. Still, I'll do some browsing and if I can come up with some kind of fix, I'll post it here.
To the best of my knowledge this has never worked in a livecd or chroot environment. Which is what it looks like due to the "livecd" prompt. I can verify that it does work once you boot the actual system though. I've always had to run grub-mkconfig once booted into my install to get my windows partition to show up in grub. Maybe its due to udev not actually running inside the chroot...I don't know. When using lvm it'll toss a warning about lvmetad because lvm isn't running in the chroot so maybe...its a similar reason with udev.
The problem appears to be related to the lack of a --bind mounted /run/udev in the chrooted environment. See https://wiki.gentoo.org/wiki/GRUB2#os-prober_and_UEFI_in_chroot.
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=cafa4c43d97fd9b6b12fa5a25fa82ef2a14304d8 commit cafa4c43d97fd9b6b12fa5a25fa82ef2a14304d8 Author: Peter Levine <plevine457@gmail.com> AuthorDate: 2021-03-25 01:35:28 +0000 Commit: Ben Kohler <bkohler@gentoo.org> CommitDate: 2021-03-26 17:44:38 +0000 sys-boot/os-prober: Add new elog info Add a message about the necessity of bind mounting /run/udev. Also, warn about the defaulting of GRUB_DISABLE_OS_PROBER=true with grub-mkconfig. Closes: https://bugs.gentoo.org/761475 Package-Manager: Portage-3.0.17, Repoman-3.0.2 Signed-off-by: Peter Levine <plevine457@gmail.com> Signed-off-by: Ben Kohler <bkohler@gentoo.org> sys-boot/os-prober/os-prober-1.78.ebuild | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
The bug has been referenced in the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=84564ed5e8df1bf6240aa2b5401562ff81e27081 commit 84564ed5e8df1bf6240aa2b5401562ff81e27081 Author: Peter Levine <plevine457@gmail.com> AuthorDate: 2021-10-08 01:46:36 +0000 Commit: Ben Kohler <bkohler@gentoo.org> CommitDate: 2021-10-08 11:12:21 +0000 sys-boot/os-prober: fix os-prober in chroot and no mounted /run/udev When /run/udev isn't mounted or udev isn't available, fallback to blkid. Bug: https://bugs.gentoo.org/761475 Package-Manager: Portage-3.0.26, Repoman-3.0.3 Signed-off-by: Peter Levine <plevine457@gmail.com> Signed-off-by: Ben Kohler <bkohler@gentoo.org> .../os-prober-1.79-efi-chroot-blkid-fallback.patch | 24 ++++++++++++++++++++++ sys-boot/os-prober/os-prober-9999.ebuild | 3 +-- 2 files changed, 25 insertions(+), 2 deletions(-)
