Gentoo Archives: gentoo-dev

From: Joost Roeleveld <joost@××××××××.org>
To: gentoo-dev@l.g.o
Subject: Re: [gentoo-dev] udev and /usr
Date: Thu, 15 Sep 2011 21:57:09
Message-Id: 7246502.pGK5je4cUZ@eve
In Reply to: Re: [gentoo-dev] udev and /usr by Rich Freeman
1 On Thursday, September 15, 2011 04:27:35 PM Rich Freeman wrote:
2 > On Thu, Sep 15, 2011 at 4:03 PM, Joost Roeleveld <joost@××××××××.org> wrote:
3 > > On Thursday, September 15, 2011 09:27:06 AM Zac Medico wrote:
4 > > > It should be similar to how sys-apps/v86d is used for uvesafb
5 > > > support.
6 > > > It installs /usr/share/v86d/initramfs and when you configure your
7 > > > kernel, you set CONFIG_INITRAMFS_SOURCE="/usr/share/v86d/initramfs"
8 > > > in
9 > > > order to have in included in your kernel image.
10 > >
11 > > Will this be set somewhere globally to the initramfs automatically?
12 > > And doesn't this mean that a new kernel will need to be build just to
13 > > satisfy
14 > > this?
15 > >
16 > > I'm trying to think of how best to avoid users who are not aware to get
17 > > caught
18 > > with non-booting systems.
19 > >
20 > > Wouldn't automatic inclusion into grub.conf be a better approach? Not
21 > > sure if
22 > > grub.conf can handle a "global" setting for initramfs.
23 >
24 > Well, the only way to set a kernel config parameter is to rebuild the
25 > kernel. There might be some way to extract the built-in initramfs (every
26 > kernel has one) and replace it with the new one without rebuilding it, but I
27 > doubt most users would prefer that we mount /boot and start modifying their
28 > kernel images.
29
30 I wasn't actually talking about changing kernels, but was wondering if
31 grub.conf has some option for a "global" initramfs. I couldn't find anything
32 in the manpage.
33
34 > Changes to grub.conf will only be properly merged if /boot is mounted, if
35 > grub is installed (don't laugh - I checked and since my system was migrated
36 > so many times I don't actually have the package installed any longer), and
37 > the user actually merges the changes in. Fiddling with grub.conf isn't
38 > exactly risk-free either.
39
40 I know, which is why I was asking for a "default" option for the initrd/module
41 part.
42
43 > I think something like this is best handled via news.
44
45 And perhaps also an announcement on gentoo-user. I think a lot of users are
46 subscribed to there.
47
48 > Note also that depending on your definition of "broken" the separate /usr
49 > situation is already broken. It will probably steadily become more broken
50 > over time, so when it stops booting altogether for any particular user might
51 > happen anytime from a year ago to never.
52
53 In what way is it broken?
54 I've only seen comments about where some udev-rules seem to expect /usr to be
55 present when run and udev not properly handling these cases. (I know this is
56 the very short version)
57
58 If an installation works and none of the udev-rules depend on /usr (or /var,
59 ....) then a seperate /usr should not be considered "broken".
60 My desktop is up-to-date and none of my udev-rules even have a "RUN+=" part.
61
62 Only my server has these for Xen-devices and these aren't run until
63 "xendomains" starts and this is quite late in the boot-sequence.
64
65 All my machines have /usr on LVM.
66
67 --
68 Joost