start_udev

start_udev

[rich turner]

i am trying to understand exactly what start_udev does.

running fc3 with / on lvm. the initrd created by fc3 works fine and
i realize using fc3's mkinitrd would solve the problem but i want to
understand what is happending.

i have created my own initrd that basically creates the root filesystem
device and exits to allow the kernel to mount the / filesystem. i do not
mount /dev in the initrd or start_udev in the initrd. this all works
fine.

when the initrd exits it executes init (rc.sysinit). everything is fine
until it comes to a line in rc.sysinit to start_udev. then i lose the
devices /dev/vg0/rootlv and checking the root filesystem fails because
there is no device by that name. i still have /dev/dm-255 but my
_real_device_names_ are gone. i could change /etc/fstab to use
/dev/dm-255 but i prefer to use _real_names_

i see that one of the things that start_udev does is mount a tmpfs on
/dev.

does start_udev mount /dev if it already is not mounted?

what is strange is that with the initrd created by fc3 (which does mount
and start udev in the initrd), after running start_udev the
_real_device_names_ for my logical volumes are still there.

does start_udev populate the new /dev with old entries found in the /dev
populated by the initrd?

thanks in advance for any help



-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now. 
http://productguide.itmanagersjournal.com/
_______________________________________________
Linux-hotplug-devel mailing list  http://linux-hotplug.sourceforge.net
Linux-hotplug-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel

Re: start_udev

[Greg KH]

On Tue, Dec 14, 2004 at 05:19:07PM -0800, rich turner wrote:
> i am trying to understand exactly what start_udev does.

It scans sysfs and creates "fake" udev events based on the dev files
found in sysfs.  I recommend using udevstart instead as it's much faster
and handles the "which order to create things in" issues which it sounds
like you need.

As for your other questions, I think a fedora mailing list would be
better, as those issues are specific to your distro.

thanks,

greg k-h


-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now. 
http://productguide.itmanagersjournal.com/
_______________________________________________
Linux-hotplug-devel mailing list  http://linux-hotplug.sourceforge.net
Linux-hotplug-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel

start_udev

[Russell Coker]

In Fedora there is a shell script named /sbin/start_udev.  This script is run 
from rc.sysinit to setup sym-links etc on a tmpfs /dev.  In the most strict 
configuration of the strict policy initrc_t does not have the required access 
to device_t.  I currently have start_udev labelled as udev_exec_t which makes 
this work.

Which is worse, allowing initrc_t to transition to udev_t by a shell script or 
just giving initrc_t extra privs?

-- 
http://www.coker.com.au/selinux/   My NSA Security Enhanced Linux packages
http://www.coker.com.au/bonnie++/  Bonnie++ hard drive benchmark
http://www.coker.com.au/postal/    Postal SMTP/POP benchmark
http://www.coker.com.au/~russell/  My home page

--
This message was distributed to subscribers of the selinux mailing list.
If you no longer wish to subscribe, send mail to majordomo@tycho.nsa.gov with
the words "unsubscribe selinux" without quotes as the message.

Re: start_udev

[Luke Kenneth Casson Leighton]

any chance that script could be pushed upstream so that debian can use
it and stop creating those same symlinks from /etc/init.d/udev?

On Fri, Sep 24, 2004 at 03:39:57AM +1000, Russell Coker wrote:
> In Fedora there is a shell script named /sbin/start_udev.  This script is run 
> from rc.sysinit to setup sym-links etc on a tmpfs /dev.  In the most strict 

--
This message was distributed to subscribers of the selinux mailing list.
If you no longer wish to subscribe, send mail to majordomo@tycho.nsa.gov with
the words "unsubscribe selinux" without quotes as the message.

Re: start_udev

[Russell Coker]

On Fri, 24 Sep 2004 07:07, Luke Kenneth Casson Leighton <lkcl@lkcl.net> wrote:
> any chance that script could be pushed upstream so that debian can use
> it and stop creating those same symlinks from /etc/init.d/udev?

It would probably be best for someone who uses udev on Debian (such as you) to 
go to 
http://download.fedora.redhat.com/pub/fedora/linux/core/development/SRPMS/ , 
download the rpm package and use rpm2cpio to extract the file and make a 
Debian bug report with the file attached.

-- 
http://www.coker.com.au/selinux/   My NSA Security Enhanced Linux packages
http://www.coker.com.au/bonnie++/  Bonnie++ hard drive benchmark
http://www.coker.com.au/postal/    Postal SMTP/POP benchmark
http://www.coker.com.au/~russell/  My home page

--
This message was distributed to subscribers of the selinux mailing list.
If you no longer wish to subscribe, send mail to majordomo@tycho.nsa.gov with
the words "unsubscribe selinux" without quotes as the message.