Gentoo Archives: gentoo-user

From: Jack <ostroffjh@×××××××××××××××××.net>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] Re: Does root=PARTUUID=<> work with DOS partition table?
Date: Thu, 25 Jul 2019 15:47:47
Message-Id: ff4c3890-805b-cefd-fa2d-2a7061319518@users.sourceforge.net
In Reply to: [gentoo-user] Re: Does root=PARTUUID=<> work with DOS partition table? by Grant Edwards
1 When you get the grub prompt, hit "e" for edit mode, or maybe better "c"
2 for command line.  By typing "root (" and hitting tab, it should let you
3 know what disks it sees.  If you're not sure which disk is which which,
4 accept one (such as hd0) and then hit tab to see the partitions it sees.
5
6 Possible reasons (mainly pulled out of thin air) does the partition need
7 the boot flag set?  do you need to specify rootfs type?
8
9 On 7/25/19 11:25 AM, Grant Edwards wrote:
10 > On 2019-07-25, Grant Edwards <grant.b.edwards@×××××.com> wrote:
11 >
12 >> All the examples I can find of people using root=PARTUUID=<> show the
13 >> longer PARTUUID values you get with a GPT parition table. Does the
14 >> root=PARTUUID=<> mechanism only work with GPT and not with DOS
15 >> parition tables?
16 > The comments in the kernel source certinaly indicate that DOS PARTUUID
17 > values should work. From init/do_mounts.c:
18 >
19 > /*
20 > * Convert a name into device number. We accept the following variants:
21 > [...]
22 > * 6) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the
23 > * unique id of a partition if the partition table provides it.
24 > * The UUID may be either an EFI/GPT UUID, or refer to an MSDOS
25 > * partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero-
26 > * filled hex representation of the 32-bit "NT disk signature", and PP
27 > * is a zero-filled hex representation of the 1-based partition number.
28 > [...]
29 >
30 > I've also tried just passing root=/dev/sdb1 (which in the current
31 > setup is consistently the device the root partition shows up on).
32 > That doesn't work either and I'm begining to suspect that the kernel
33 > simply isn't recognizing the USB storage device at all.
34 >
35 > I wish I could figure out how to get scrollback to work so I could see
36 > all of the kernel messages before the panic...
37 >