Got udev working, now what?!

Message

at_chaos · Post by **at_chaos** » Sun Dec 14, 2003 9:26 pm

Let's move on to get udev working and desclose its secret.

This topic is carried over from http://forums.gentoo.org/viewtopic.php?t=114303

Decibels wrote:Due to some things recently discovered, I wouldn't do away with devfs just yet. Unless you want to run a 'unstable' system. Seems pretty stable to me so far though.

Yes. I use lilo, but removed the mounting option for devfs. That is probably why it is complaining. So just remove it from your grub bootloader.

If you want to use udev instead of devfs, then you will also need baselayout-1.8.6.12-r2 or probably at least anything 1.8.6.12 (haven't checked r1 or so). It won't work without it properly. Cause it needs to have the init.d scripts to mount ramfs at /dev, there is also a tar file /lib/udev-state/devices.tar.bz2 that is will use. So needs the new baselayout. When you reboot you will see this, goes real fast on my system so hard to see:

'mounting sysfs at /sys'
'mounting ramfs at /dev'
'configuring system to use udev'
'using /sbin/hotplug for udev management'

Without this, it is really just like the old way before devfs, that is why I said what I did at the beginning. If your not having any problems, like me, than go for it. Not using it for my main system though till know it is stable (mostly).

I emerged that with --nodeps flag. Everything seems to be working pretty good as far as starting. Konsole for kde says 'Unable to open a suitable terminal device' (my fault, troubleshooting and took myself out of tty group). So fixed.

*Probably ought to start another thread instead of using this one also. It started out about something else and is moving in a different direction. Or just send me a private message.

There is now way out now, I will try to get it working too.

at_chaos · Post by **at_chaos** » Sun Dec 14, 2003 9:39 pm

don't know if it is working on my system because I have already baselayout 1.8.6.10-r1 -> how can I check if udev is working

/sys shows me block,bus,cdev,class,devices,firmware,power

don't have /dev/ramfs -> but it is in the kernel

greets,
andy

Decibels · Post by **Decibels** » Sun Dec 14, 2003 9:49 pm

Recap of how to put UDEV in place from some of previous discussion.
*Note, some of your devices may not be created in /dev now. Examples are: alsa devices, nvidia devices. You will have to manually create them until then. Read further down if don't know how.

1) emerge udev (at least 007)
2) That also gives you sysfsutils-0.3.0
3) Didn't have hotplug-20030805-r2 in runlevels so: rc-update add hotplug boot
4) Some of my /usr/src/linux/.config

Code: Select all

 
# Bus options (PCI, PCMCIA, EISA, MCA, ISA) 
# 
CONFIG_HOTPLUG=y 
# 
# File systems 
# 
# Pseudo filesystems 
# 
CONFIG_PROC_FS=y 
CONFIG_PROC_KCORE=y 
# CONFIG_DEVFS_FS is not set 
CONFIG_DEVPTS_FS=y 
# CONFIG_DEVPTS_FS_XATTR is not set 
CONFIG_TMPFS=y 
# CONFIG_HUGETLBFS is not set 
# CONFIG_HUGETLB_PAGE is not set 
CONFIG_RAMFS=y

5) Then as root: mkdir /sys
To create the folder for sysfs and udev to use. Note: This should be automatically created, but already added manually, so might
be created now by the system.

6) To /etc/fstab add: none /sys sysfs defaults 0 0
If you don't want to reboot, you could type in: mount -t sysfs none /sys
To work with it.

7) Also in /etc/fstab for 2.6 kernel, added: none /dev/pts devpts defaults 0 0

8 ) Then you need to emerge baselayout-1.8.6.12-r2 . Haven't check, but think needs
to be at least 1.8.6.12 version. Above version does have the necessary init.d scripts,..
Make sure you put the new config files in place that need updating by running etc-update.
If you don't, then it won't save your current /dev folder in /lib/udev-state/devices/devices.tar.bz2 .
And then you will have to for example remerge programs that make devices in /dev like nvidia-kernel each time you reboot.

9) Then at reboot you will see:

'mounting sysfs at /sys'
'mounting ramfs at /dev'
'configuring system to use udev'
'populating /dev with device nodes'
'using /sbin/hotplug for udev management'

End of Recap.

****************

There are a few utils that come with it. But you will get these to work even if you don't have the new baselayout.

One is 'lsbus' you can see with:

bash-2.05b# lsbus -d usb
Bus: usb
Devices:
1-2:1.0:
Driver: microtekX6

1-2:
Driver: usb

1-1:1.0:
Driver: hid

1-1:
Driver: usb

2-0:1.0:
Driver: hub

usb2:
Driver: usb

1-0:1.0:
Driver: hub

usb1:
Driver: usb

Another is 'systool' :

bash-2.05b# systool -b pci
Bus: pci
Devices:
0000:01:05.0: 10de:0110
0000:00:0f.0: 1317:0985
Driver: tulip
0000:00:0e.0: 1274:5880
Driver: ENS1371
0000:00:0d.0: 1317:0985
Driver: tulip
0000:00:0c.0: 14f1:1036
0000:00:07.4: 1106:3057
Driver: via686a
0000:00:07.3: 1106:3038
Driver: uhci_hcd
0000:00:07.2: 1106:3038
Driver: uhci_hcd
0000:00:07.1: 1106:0571
Driver: VIA IDE
0000:00:07.0: 1106:0686
Driver: parport_pc
0000:00:01.0: 1022:700f
0000:00:00.0: 1022:700e
Driver: agpgart-amdk7

Unplug the scanner and you will see it disappear. Though if you don't have the newest baselayout, then it isn't really doing anything with the info.

Even then, at this junction, I am not sure how much, if any, it is really doing anything. Have new devices created/modified in /dev but not seeing anything change there when unplug the scanner, just in /sys.

If you have the new baselayout you will see this during boot, right after the mounting /proc:

mounting sysfs at /sys
mounting ramfs at /dev
configuring system to use udev
using /sbin/hotplug for udev management

and you will have compressed file called: /lib/udev-state/devices.tar.bz2
That it gets the new device layout from. And should see a lot or most of your /dev files changed to the date you installed it. Infact looks like mine has all been changed now, didn't seem like that at first. Baselayout won't do this though if you are using devfs.

Will have to play with it some more and see.

The lsbus and systool comes from sysfsutils: http://linux-diag.sourceforge.net/Sysfsutils.html[/quote]

From the 2.6 kernel help on devfs:

Note that devfs no longer manages /dev/pts! If you are using UNIX98
ptys, you will also need to enable (and mount) the /dev/pts
filesystem (CONFIG_DEVPTS_FS).

Note that devfs has been obsoleted by udev,
<http://www.kernel.org/pub/linux/utils/kernel/hotplug/>.
It has been stripped down to a bare minimum and is only provided for
legacy installations that use its naming scheme which is
unfortunately different from the names normal Linux installations
use.

http://lwn.net/Articles/50731/

http://lwn.net/Articles/28526/

http://kerneltrap.org/node/view/1668

http://kernel.org/pub/linux/utils/kerne ... g/udev-FAQ

at_chaos · Post by **at_chaos** » Sun Dec 14, 2003 10:07 pm

hope you had the same problems:

after install of the new baselayout and trying to use pptp error that there is no /dev/ppp device

tryed to start X -> error there is no screen (how can i fix this?)

hm... there was no error msg during boot up ... i saw also that /sys and /dev were mounted

any ideas?

Decibels · Post by **Decibels** » Sun Dec 14, 2003 10:18 pm

Don't have a /dev/ppp either, don't see it on my 2.4 kernel partition either, either a bug, or something. Haven't had a dial-up modem for quite a long while so don't know. You might have to create it until that is fixed, if that is the case that they forgot to include it in the tarball.

For X problem:
Check your /var/log/XFree86.0.log file. I did have to remerge nvidia-kernel after cause the nvidiactrl and think nvidia0 or something was missing. After that X started up fine and Kde was running.

at_chaos · Post by **at_chaos** » Sun Dec 14, 2003 10:34 pm

hi decibels,

after reemerging nvidia-kernel gnome is working fine.. don't know but it seems to start up faster

I need ppp because of my adsl connection and it seems to be a bug because /dev/ppp is just not there but the system told me how to build it

Don't really know what i have done the last 2 hours but I think udev is working.. not fine but working

I hope the 2.6.0 including baselayout and udev come to a stable release soon so that the system is running as smooth as with the 2.4.20-gentoo-sources

so far

Decibels · Post by **Decibels** » Sun Dec 14, 2003 10:39 pm

Great!! Ya, I want more documentation also. Still don't really know what need to do with the config file in /etc/udev/ which they keep changing the name of. Well, hopefully stuff starts coming out since people are starting to mess with it. This post is a good example.

at_chaos · Post by **at_chaos** » Mon Dec 15, 2003 8:33 am

seems that udev has problems to create devices on startup

on every reboot I have to emerge nvidia and add my /dev/ppp device...

udev-008 is in portage now

charlieg · Post by **charlieg** » Mon Dec 15, 2003 10:21 am

at_chaos wrote:on every reboot I have to emerge nvidia and add my /dev/ppp device...

You shouldn't have to emerge nvidia, just drop it into /etc/modules.autoload.d/kernel-2.6?

at_chaos · Post by **at_chaos** » Mon Dec 15, 2003 10:30 am

charlieg wrote: You shouldn't have to emerge nvidia, just drop it into /etc/modules.autoload.d/kernel-2.6?

Hi,
that's not the problem. Nvidia is loaded by modules.autoload.d but it's also another /dev problem (i think) because the error tells me that he didn't find a screen.

I just reemerge because I do not know how to add /dev/nvidiactl manually. And when I emerge nvidia again it is created

Don't know how to fix that.

TheCoop · Post by **TheCoop** » Mon Dec 15, 2003 10:39 am

run /sbin/NVmakedevices.sh or something like that

at_chaos · Post by **at_chaos** » Mon Dec 15, 2003 11:11 am

ok thx I will try it when I'm at home.

Do I have to run it after every reboot? I think so but we will see

TheCoop · Post by **TheCoop** » Mon Dec 15, 2003 11:49 am

i dont have to run it, if devfsd isnt installed then the nodes should just be created...

at_chaos · Post by **at_chaos** » Mon Dec 15, 2003 2:02 pm

So I have to add the nodes I want to load into some startscripts. Hm.. does anyone know if this will be fixed and the devices will be builded automatically on startup. e.g. ppp nvidiactl etc?

Decibels · Post by **Decibels** » Mon Dec 15, 2003 2:49 pm

Hi at_chaos,

No, the nvidiactl is there. I will have to look thru the init scripts in a bit. Here is why. I think it reconstitutes itself in /lib/udev-state/devices.tar.bz2 (hence the name udev-state) when you shut down each time. Looking in my .bz2 I have these. Were they there from creation or did it save the udev-state after I emerged it again and rebooted?

Code: Select all

crw------- root/root     195,0 2003-12-14 06:46:26 nvidia0
crw------- root/root     195,1 2003-12-14 06:46:26 nvidia1
crw------- root/root     195,2 2003-12-14 06:46:26 nvidia2
crw------- root/root     195,3 2003-12-14 06:46:26 nvidia3
crw------- root/root     195,4 2003-12-14 06:46:26 nvidia4
crw------- root/root     195,5 2003-12-14 06:46:26 nvidia5
crw------- root/root     195,6 2003-12-14 06:46:26 nvidia6
crw------- root/root     195,7 2003-12-14 06:46:26 nvidia7
crw------- root/root   195,255 2003-12-14 06:46:26 nvidiactl

You shouldn't have to remerge nvidia-kernel each time. I only had to do it to get the device after emerging the baselayout, so good chance it added to the tarball.

Later: Ya, here it is. In /etc/init.d/halt.sh . It looks to see if you are using devfs or have .udev in /dev. If you have .udev it recreates the tarball, so if you emerged nvidia-kernel after emerging baselayout, it should save the state of the /dev folder in the /lib/udev-state.

Code: Select all

# We need to properly terminate devfsd to save the permissions
if [ -n "`ps --no-heading -C 'devfsd'`" ]
then
	ebegin "Stopping devfsd"
	killall -15 devfsd &>/dev/null
	eend $?
elif [ ! -e /dev/.devfsd -a -e /dev/.udev ]
then
	ebegin "Saving device nodes"
	cd /dev
	try tar -jclpf "/tmp/devices-$$.tar.bz2" *
	try mv -f "/tmp/devices-$$.tar.bz2" /lib/udev-state/devices.tar.bz2
	eend 0
fi

It is part of the baselayout.

Code: Select all

bash-2.05b# qpkg -f -v /etc/init.d/halt.sh
sys-apps/baselayout-1.8.6.12-r2 *

So, if you don't have that in /etc/init.d/halt.sh emerge the baselayout above.

Okay udev-008 in portage now. Emerging it and going to start playing with that config file.

TheCoop · Post by **TheCoop** » Mon Dec 15, 2003 3:46 pm

I couldnt understand the config files, afaics they dont do anything atm...

at_chaos · Post by **at_chaos** » Mon Dec 15, 2003 3:51 pm

Hi Decibels,

I think the devices were created. In my .bz2 there are thousands of files exept the nvida files you listet.

Code: Select all

web temp # ls n*
nst0  nst0a  nst0l  nst0m  nst1  nst1a  nst1l  nst1m  null

Thanks to TheCoop I now don't reemerge nvidia-kernel every time but i have to run /sbin/NVmakedevices.sh (after every startup)

In the .bz2 file there should also be my ppp device but it isn't there -> what did I wrong

-> I now checked my halt.sh and figured out that i do not have the lines you mentioned altough I have the latest baselayout -> I will reemerge and post it

at_chaos · Post by **at_chaos** » Mon Dec 15, 2003 5:02 pm

IT WORKS!

(I didn't work because I was too scared to install the new config files -> just added all new /etc/init.d/ config files and deleted the new fstab file etc.)

there is now just a new problem: on boot i get the error message:

the setfont executable was not found

Maybe i should start a new thread with this issue.

THANKS!

Decibels · Post by **Decibels** » Mon Dec 15, 2003 11:29 pm

Setfont error. I get that too, but haven't looked into it yet. Maybe tomorrow.

It's usually a good idea to backup your /etc files periodically or just before a config update so you can always put them back if have a problem with updates on them. I have a script I run with a cronjob to back my /home and /etc folder up to a backup partition.

Well, didn't take as long as thought. Did a quick search and found.

Code: Select all

bash-2.05b$ qpkg -f /usr/bin/setfont
sys-apps/kbd

So:
      Latest version available: 1.08-r4
      Latest version installed: 1.06-r1
      Size of downloaded files: 800 kB
      Homepage:    http://freshmeat.net/projects/kbd/
      Description: Keyboard and console utilities

Works, rebooted and error gone. Just upgrade kbd, cause it is there, but wants the new one.

at_chaos · Post by **at_chaos** » Tue Dec 16, 2003 10:14 am

hehe, works for me too. thx a lot!

But... hm..
The last 3 days I was just playing around with root and yesterday I started gnome as user and when I wanted to go to Terminal to su to root I saw that I get just a blank terminal. (There is no way to get my terminal running as user)

I do not get a "chaos@mybox:#" or sth like that. With root it works. After reemerging the same problem.

Just another side effect?

Decibels · Post by **Decibels** » Tue Dec 16, 2003 3:02 pm

I don't think it is a side effect of udev installation. Did you by chance bork your ~/.bashrc file? I send mine to you pm.

dreambox · Post by **dreambox** » Tue Dec 16, 2003 9:08 pm

Did anyone get udev working with lvm2? vgchange -ay says it doesn't find /dev/mapper/control

Decibels · Post by **Decibels** » Wed Dec 17, 2003 12:13 am

Little problem has developed! Not sure when it began, guess didn't keep good enough chronological notes. At one point I was able to remerge the nvidia kernel and it created the devices in /dev like nvididactl. Then noticed could not start alsamixer or amixer (sound still works, I guess do to aRts, not sure, no alsa devices now, but sound still works, weird).

After numerous tries, remerging udev-007, putting 008 back,... wrote a bug report. Got reply: http://bugs.gentoo.org/show_bug.cgi?id=35955
So there are some things that will not create devices in there.

The real kicker is that I can manually create them myself in there and it is fine upon next reboot. Run for example alsaconf and it won't even create the devices in there. So manually created /dev/snd/controlC0, controlC1, controlC2, rebooted and still there and alsamixer, amixer works again. Saved state again with alsactl store 0.

What I suggest until this is fixed is to manually create it. Went to my main partition, mounted the root partition with the udev system on it. Made a list of all the items with major node of 116 (for your /dev/mapper/control just ls -l that folder) and used mknod to recreate it. *Yes the alsa stuff is still there as long as udev isn't mounted on ramfs, you can see it and get the info.

For alsa here is a short list to at least get you started.

mknod -m 600 /dev/snd/controlC0 c 116 0
mknod -m 600 /dev/snd/controlC1 c 116 32
mknod -m 600 /dev/snd/controlC2 c 116 64
mknod -m 600 /dev/snd/controlC3 c 116 96

Then: chgrp audio /dev/devicename
The first one got my alsamixer working again.

Nvidia devices:

mknod -m 600 /dev/nvidia0 c 195 0
"".....""........""......" /nvidia1 ""..... 1
thru
mknod -m 600 /dev/nvidia7 c 195 7
mknod -m 600 /dev/nvididactl c 195 255

chown me /dev/nvidida#
chown me /dev/nvididactl

**Later. Worked up a quick and dirty script if anyone wants to try it. Change the owner to YOU or whatever it was for the 'nvidia' devices, mine was set to me. Remove any items you don't want or need. It won't overwrite anything so shouldn't be problem if you leave in. Reboot and should see that everything is still there.

Code: Select all

#!/bin/bash
## Script to create some devices in /dev for udev that are 
## not included yet.
echo "Creating Devices for Alsa for one audio card in /dev/snd"
mkdir /dev/snd
mknod -m 600 /dev/snd/controlC0 c 116 0
mknod -m 600 /dev/snd/hwC0D0 c 116 4
mknod -m 600 /dev/snd/hwC0D1 c 116 5
mknod -m 600 /dev/snd/hwC0D2 c 116 6
mknod -m 600 /dev/snd/hwC0D3 c 116 7
mknod -m 600 /dev/snd/midiC0D0 c 116 8
mknod -m 600 /dev/snd/midiC0D1 c 116 9
mknod -m 600 /dev/snd/midiC0D2 c 116 10
mknod -m 600 /dev/snd/midiC0D3 c 116 11
mknod -m 600 /dev/snd/midiC0D4 c 116 12
mknod -m 600 /dev/snd/midiC0D5 c 116 13
mknod -m 600 /dev/snd/midiC0D6 c 116 14
mknod -m 600 /dev/snd/midiC0D7 c 116 15
mknod -m 600 /dev/snd/pcmC0D0c c 116 24
mknod -m 600 /dev/snd/pcmC0D0p c 116 16
mknod -m 600 /dev/snd/pcmC0D1c c 116 25
mknod -m 600 /dev/snd/pcmC0D1p c 116 17
mknod -m 600 /dev/snd/pcmC0D2c c 116 26
mknod -m 600 /dev/snd/pcmC0D2p c 116 18
mknod -m 600 /dev/snd/pcmC0D3c c 116 27
mknod -m 600 /dev/snd/pcmC0D3p c 116 19
mknod -m 600 /dev/snd/pcmC0D4c c 116 28
mknod -m 600 /dev/snd/pcmC0D4p c 116 20
mknod -m 600 /dev/snd/pcmC0D5c c 116 29
mknod -m 600 /dev/snd/pcmC0D5p c 116 21
mknod -m 600 /dev/snd/pcmC0D6c c 116 30
mknod -m 600 /dev/snd/pcmC0D6p c 116 22
mknod -m 600 /dev/snd/pcmC0D7c c 116 31
mknod -m 600 /dev/snd/pcmC0D7p c 116 23
mknod -m 600 /dev/snd/seq c 116 1
mknod -m 600 /dev/snd/timer c 116 33
chgrp audio /dev/snd/*
echo "Done creating Alsa devices for one audio card in /dev/snd"
echo "Creating Devices for Alsa for one audio card in /dev"
mknod -m 600 /dev/admmidi0 c 14 14
mknod -m 600 /dev/admmidi1 c 14 30
mknod -m 600 /dev/admmidi2 c 14 46
mknod -m 600 /dev/admmidi3 c 14 62
chgrp audio /dev/admmidi*
mknod -m 600 /dev/adsp0 c 14 12
mknod -m 600 /dev/adsp1 c 14 28
mknod -m 600 /dev/adsp2 c 14 44
mknod -m 600 /dev/adsp3 c 14 60
chgrp audio /dev/adsp*
mknod -m 600 /dev/amidi0 c 14 13
mknod -m 600 /dev/amidi1 c 14 29
mknod -m 600 /dev/amidi2 c 14 45
mknod -m 600 /dev/amidi3 c 14 61
chgrp audio /dev/amidi*
mknod -m 600 /dev/amixer0 c 14 11
mknod -m 600 /dev/amixer1 c 14 27
mknod -m 600 /dev/amixer2 c 14 43
mknod -m 600 /dev/amixer3 c 14 59
chgrp audio /dev/amixer*
mknod -m 600 /dev/dmfm0 c 14 10
mknod -m 600 /dev/dmfm1 c 14 26
mknod -m 600 /dev/dmfm2 c 14 42
mknod -m 600 /dev/dmfm3 c 14 58
chgrp audio /dev/dmfm*
mknod -m 600 /dev/dmmidi0 c 14 9
mknod -m 600 /dev/dmmidi1 c 14 25
mknod -m 600 /dev/dmmidi2 c 14 41
mknod -m 600 /dev/dmmidi3 c 14 57
chgrp audio /dev/dmmidi*
mknod -m 600 /dev/mixer0 c 14 0
mknod -m 600 /dev/mixer1 c 14 16
mknod -m 600 /dev/mixer2 c 14 32
mknod -m 600 /dev/mixer3 c 14 48
chgrp audio /dev/mixer*
mknod -m 600 /dev/music c 14 8
chgrp audio /dev/music
echo "Done creating Alsa devices for one audio card in /dev/snd"
echo "Creating symlinks for Alsa."
ln -s /dev/adsp0 /dev/adsp
ln -s /dev/amidi0 /dev/amidi
ln -s /dev/midi0 /dev/midi
ln -s /dev/music /dev/sequencer2
echo "Done creating symlinks for Alsa."
echo "Creating nvidia devices in /dev"
mknod -m 600 /dev/nvidia0 c 195 0
mknod -m 600 /dev/nvidia1 c 195 1
mknod -m 600 /dev/nvidia2 c 195 2
mknod -m 600 /dev/nvidia3 c 195 3
mknod -m 600 /dev/nvidia4 c 195 4
mknod -m 600 /dev/nvidia5 c 195 5
mknod -m 600 /dev/nvidia6 c 195 6
mknod -m 600 /dev/nvidia7 c 195 7
mknod -m 600 /dev/nvidiactl c 195 255
chown decibels /dev/nvidia*    #add whatever yours had here before, mine was my name.
echo "Done creating nvidia devices in /dev"
echo "Creating misc items missing."
# remove this if you don't think need
mknod -m 600 /dev/beep c 10 128
chgrp audio /dev/beep
mknod -m 660 /dev/pcaudio c 13 4
chgrp audio /dev/pcaudio
mknod -m 660 /dev/pcmixer c 13 0
chgrp audio /dev/pcmixer
mknod -m 660 /dev/pcsp c 13 3
chgrp audio /dev/pcsp
mknod -m 660 /dev/hfmodem c 10 145
echo "Done creating misc items missing."
exit 0

Decibels · Post by **Decibels** » Wed Dec 17, 2003 4:12 am

dreambox wrote:Did anyone get udev working with lvm2? vgchange -ay says it doesn't find /dev/mapper/control

Try this:

mkdir /dev/mapper
mknod -m 600 /dev/mapper/control c 10 63

That is the best can do, never used it before. The owner and group is probably: root root
Not sure about permission, more than likely 600.

Lolo- · Post by **Lolo-** » Wed Dec 17, 2003 8:11 am

nota: DO NOT UNMERGE DEVFSD

or there's a trick I didn't catch