Gentoo Archives: gentoo-user

From: Adam Carter <adamcarter3@×××××.com>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] Verify uefi installation
Date: Mon, 23 Sep 2019 23:31:28
Message-Id: CAC=wYCG7fBzVvTmUxBBAp9BEzJXxSiVgb4bBmdYCdFi1QG_+1Q@mail.gmail.com
In Reply to: Re: [gentoo-user] Verify uefi installation by Mick
1 >
2 > > Looks like the setting gets cleared with every BIOS update. I assume this
3 > > is due to shitty coding by the MB manufacturer and not a limitation of
4 > UEFI.
5 >
6 > An update of the firmware flashes the UEFI EEPROM and as far as I have
7 > experienced no settings are retained.
8
9
10 A backward step from older MBR / BIOS functionality then. I guess that
11 indicates that code and configuration are not separated.
12
13
14 > A fresh probe of MoBo devices at first boot re-lists anything bootable.
15 >
16
17 Do you find that the re-generated list only finds devices, not the .efi
18 files on those devices? (and therefore efibootmgr is still required?)
19
20
21 > Desktop/workstation UEFI firmware have more features, which allow tweaking
22 > boot lists. Some also offer a back up/restore facility for settings from
23 > a
24 > file.
25 >
26 > Laptop UEFI boot menus are more sparce, in which case efibootmgr, or with
27 > systemd-boot the bootctl command allow managing UEFI boot entries. I
28 > believe
29 > MSWindows have their own applications to do the same.
30 >
31
32 Ok thanks for the info.
33
34
35 > Regarding the message "GUID partition table header signature is wrong",
36 > this
37 > is probably indicative of an MBR partition table - but I'm not sure. Have
38 > you
39 > installed some OS on an MBR partition schema?
40 >
41
42 # gdisk -l /dev/nvme0n1
43 GPT fdisk (gdisk) version 1.0.4
44
45 Partition table scan:
46 MBR: protective
47 BSD: not present
48 APM: not present
49 GPT: present
50 <snip>
51 Number Start (sector) End (sector) Size Code Name
52 1 2048 1955839 954.0 MiB EF00 boot
53 2 1955840 976771071 464.8 GiB 8300 root
54
55 Not sure where the 'MBR: protective' came from as the system has been linux
56 only from the start. I guess its either the default or I made an error
57 during the build. AFAIK this is still a valid configuration, so I assume
58 the signature message is not related to that.
59
60 I guess i could just try re-writing the partition table to see if that
61 clears it.

Replies

Subject Author
Re: [gentoo-user] Verify uefi installation Neil Bothwick <neil@××××××××××.uk>