Gentoo Forums
Gentoo Forums
Gentoo Forums
Quick Search: in
udev doesn't create device nodes![Solved]
View unanswered posts
View posts from last 24 hours

 
Reply to topic    Gentoo Forums Forum Index Kernel & Hardware
View previous topic :: View next topic  
Author Message
nolim
n00b
n00b


Joined: 17 Dec 2005
Posts: 22
Location: Israel

PostPosted: Fri Apr 28, 2006 1:39 pm    Post subject: udev doesn't create device nodes![Solved] Reply with quote

Hello everybody!
I have discovered that my udev doesn't work.
/dev isn't being updated when I plug new hardware even if it had been identified by the kernel(I checked it by dmesg).
I thing /dev isn't being update at all, I have a lot of junk there.
I emerge udev and hotplug.

something that might help:
I plug in a stroge mass usb device to my computer, And it had being identified by lsusb and dmesg, but no device node had been created.
I looked for /sys and didn't find any block/sda device, seems to be that sysfs doesn't work.
Is that a kenel problem?
When I try to compile my kernel with genkernel in the menuconfig part, I can't select:
Code:
General setup --->
  [*] Support for hot-pluggable devices

I only got this:
Code:
General setup --->
--Support for hot-pluggable devices

Maybe the kernel doesn't interrupt udev to create the devices nodes?
what to do?
_________________
Linux, if it's broken fix it!
Gentoo, The Power To Be Free
FF is not FastForward...FireFox get ready!!
[img]http://nolim.er1.be/trust.gif[/img]


Last edited by nolim on Sat Apr 29, 2006 9:26 am; edited 1 time in total
Back to top
View user's profile Send private message
NeddySeagoon
Administrator
Administrator


Joined: 05 Jul 2003
Posts: 54813
Location: 56N 3W

PostPosted: Fri Apr 28, 2006 3:09 pm    Post subject: Reply with quote

nolim,

First, emerge --sync then do emerge -s udev.
If you don't have the latest version for your install, update it.

Did your problem systesm ever have devfsd installed?
See that udev is being used by watching the very early boot messages. Look for a message saying
Mounting /dev for udev
Its one of the first 3 or 4 messages.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
Back to top
View user's profile Send private message
nolim
n00b
n00b


Joined: 17 Dec 2005
Posts: 22
Location: Israel

PostPosted: Fri Apr 28, 2006 3:48 pm    Post subject: Reply with quote

udev is the one who mounts /dev.
devfs hadn't been install.
emerge -pv devfsd indicates that it is not installed right now, and I am sure I hadn't install it before.
_________________
Linux, if it's broken fix it!
Gentoo, The Power To Be Free
FF is not FastForward...FireFox get ready!!
[img]http://nolim.er1.be/trust.gif[/img]


Last edited by nolim on Fri Apr 28, 2006 3:55 pm; edited 1 time in total
Back to top
View user's profile Send private message
NeddySeagoon
Administrator
Administrator


Joined: 05 Jul 2003
Posts: 54813
Location: 56N 3W

PostPosted: Fri Apr 28, 2006 3:54 pm    Post subject: Reply with quote

nolim,

You have the latest udev ?

Do you have all the correct USB and SCSI kernel modules for your kernel?
They may be either compiled in or made as modules. Modules must be loaded of course.

Try udevstart after you have connected your USB storage device to your PC.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
Back to top
View user's profile Send private message
nolim
n00b
n00b


Joined: 17 Dec 2005
Posts: 22
Location: Israel

PostPosted: Fri Apr 28, 2006 4:11 pm    Post subject: Reply with quote

I have a usb printer that works O.K (hp officejet 5510).
I had printed a blank page with the OO.
dmesg when I turn the printer on:
Code:
usb 1-1: new full speed USB device using uhci_hcd and address 7
drivers/usb/class/usblp.c: usblp0: USB Bidirectional printer dev 7 if 1 alt 0 proto 2 vid 0x03F0 pid 0x3A11
usbcore: registered new driver usblp
drivers/usb/class/usblp.c: v0.13: USB Printer Device Class driver

You can see that the right modules are loaded,and I am sure that my kernel had the right modules for the stroge device.
The same thing happened for the usb stroge, and nothing is written about devices nodes that had been created.
/dev/usb/lp0 had been there before I turn on the printer, I don't think It's O.K, is it?

I tried the udevstart but /dev/sda0 hadn't been created, how can I check if udev creates someting in the /dev, by dmesg?
so nothing had been created.

I will try now to update my system, thanks for your help so far.
_________________
Linux, if it's broken fix it!
Gentoo, The Power To Be Free
FF is not FastForward...FireFox get ready!!
[img]http://nolim.er1.be/trust.gif[/img]
Back to top
View user's profile Send private message
Corona688
Veteran
Veteran


Joined: 10 Jan 2004
Posts: 1204

PostPosted: Fri Apr 28, 2006 4:22 pm    Post subject: Reply with quote

Having some cruft in /dev/ before udev creates it seems a fairly normal state of affairs. I'm not sure how much it helps or hurts things, but it doesn't seem to be the end of the world. I leave it because last time I started deleting things that looked unimportant I pooched my /boot partition :D
nolim wrote:
how can I check if udev creates someting in the /dev, by dmesg?
udev is very different from devfsd... The "u" in udev means "userspace" because that's where it works -- it's not in the kernel, the kernel just passes messages to it. This means that udev will not and cannot log things to dmesg.

You can probably get it to log to /var/log/messages though. Looking in /etc/udev/udev.conf shows this interesting line:
Code:
# udev_log - set to "yes" if you want logging
udev_log="no"


Also search for udevtest. It's finicky but useful in seeing what udev thinks it's doing. Be warned, some older versions want sys paths beginning with /sys/ while newer ones want you to leave the /sys off!

p.s. did you mean /dev/sda1? I've never seen a /dev/sda0, it counts from 1.
_________________
Petition for Better 64-bit ATI Drivers - Sign Here
http://www.petitiononline.com/atipet/petition.html
Back to top
View user's profile Send private message
NeddySeagoon
Administrator
Administrator


Joined: 05 Jul 2003
Posts: 54813
Location: 56N 3W

PostPosted: Fri Apr 28, 2006 4:53 pm    Post subject: Reply with quote

nolim,

A working printer is encoraging but not suffcient to indicate that USB storage will work.
USB storage devices appear as SCSI devices, so you need the usb-storage module, the top level SCSI modules and the SCSI disk module for your kernel.
usb-storage then appears as /dev/sd? Does the output of
Code:
ls /dev/sd?
change when the device is added/removed. (The ? matches exactly one character)
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
Back to top
View user's profile Send private message
nolim
n00b
n00b


Joined: 17 Dec 2005
Posts: 22
Location: Israel

PostPosted: Fri Apr 28, 2006 8:41 pm    Post subject: Reply with quote

ls /dev/sd?? doesn't change, it give me 4 devices a-d and each one of them has numbers from 1-9.
here is the output of lsmod(relevent modules only):
Code:
Module                  Size  Used by
usblp                  12160  0
ohci_hcd               18436  0
uhci_hcd               28944  0
usb_storage            66112  0
usbcore               112388  5 usblp,ohci_hcd,uhci_hcd,usb_storage

You can see that usb_stroge had been loaded.
Note: I use usb version 1.0 only
I thing the kernel doesn't communicate with udev.

Corona688
mu udev.conf
udev_log="err"
there are no options "yes" "no", there are "err" "info" "debug"...I didn't change the value.
I didn't understand how to use udevtest. man doesn't represnt any helpful information, very short and unhelpful.
_________________
Linux, if it's broken fix it!
Gentoo, The Power To Be Free
FF is not FastForward...FireFox get ready!!
[img]http://nolim.er1.be/trust.gif[/img]
Back to top
View user's profile Send private message
NeddySeagoon
Administrator
Administrator


Joined: 05 Jul 2003
Posts: 54813
Location: 56N 3W

PostPosted: Fri Apr 28, 2006 10:10 pm    Post subject: Reply with quote

nolim,

And the high level SCSI driver ?
It sounds very much as if you have a static /dev
What does uname -a show ?
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
Back to top
View user's profile Send private message
nolim
n00b
n00b


Joined: 17 Dec 2005
Posts: 22
Location: Israel

PostPosted: Sat Apr 29, 2006 9:22 am    Post subject: Reply with quote

NeddySeagoon wrote:
And the high level SCSI driver ?

I'm so damn!!
I was sure that menuconfig selects this module automatically for me...guess not.
It didn't select all the module that were require.
thanks!!

Corona688:
here is my dmesg:
Code:
usb 1-2: new full speed USB device using uhci_hcd and address 2
scsi0 : SCSI emulation for USB Mass Storage devices
usb-storage: device found at 2
usb-storage: waiting for device to settle before scanning
  Vendor: NIKON     Model: NIKON DSC E2100   Rev: 1.00
  Type:   Direct-Access                      ANSI SCSI revision: 02
usb-storage: device scan complete
SCSI device sda: 31232 512-byte hdwr sectors (16 MB)
sda: Write Protect is off
sda: Mode Sense: 18 00 00 08
sda: assuming drive cache: write through
SCSI device sda: 31232 512-byte hdwr sectors (16 MB)
sda: Write Protect is off
sda: Mode Sense: 18 00 00 08
sda: assuming drive cache: write through
 sda: sda1
sd 0:0:0:0: Attached scsi removable disk sda

there is an addition from the line with SCSI, it wasn't there before.
I guess that this log is refer to the kernel(sysfs) and not to udev, I got confused.
It really seems to be like a udev log, thank you too for the correction.
_________________
Linux, if it's broken fix it!
Gentoo, The Power To Be Free
FF is not FastForward...FireFox get ready!!
[img]http://nolim.er1.be/trust.gif[/img]
Back to top
View user's profile Send private message
Display posts from previous:   
Reply to topic    Gentoo Forums Forum Index Kernel & Hardware All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum