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User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.0.1) Gecko/20021003

Description of problem:
Strange behavior running kernel-uml including 

  1). Hangs (or exceedingly slow startup) at random points in the
      startup process when services are started
  2). UML do not come down cleanly. Processes on the host are left
      running.
  3). Problems when mounting images


Version-Release number of selected component (if applicable):


How reproducible:
Always

Steps to Reproduce:
I have tried three difference procedures

A1. Download root_fs.rh-7.2-full.pristine.20020312.bz2 from 
    http://user-mode-linux.sourceforge.net/dl-sf.html
A2. Uncompress image
A3. Loop-mount the image
A4. Edit /etc/inittab to default to run-level 3 and alter all 'ttys/#'
    to 'tty#'.
A5. Save and umount
A6. Execute '/boot/vmlinuz-2.4.18-14uml \
      ubd0=root_fs.rh-7.2-full.pristine.20020312 con=xterm'

B1. Download root_fs_toms1.7.205.bz2 from the same site as above
B2. Uncompress image
B3. Loop-mount the image
B4. Edit /etc/inittab to default to run-level 3 and alter all 'ttys/#'
    to 'tty#'.
B5. Save and umount
B6. Execute '/boot/vmlinuz-2.4.18-14uml \
      ubd0=root_fs_toms1.7.205 con=xterm
	
C1. Follow the procedure described at http://linuxhacker.ru/uml/

I did try various settings for RAM, but to no avail.

(The RH 7.2 image are slightly altered from the version RH distributes. The
ttys/# -> tty# undoes one of these changes. If this is not done no terminals
will start and you'll be unable to log in)


Actual Results:  
A: Hangs:

The hangs are coming at rather random points in the service startup process (the
earliest one is if the disk is to be fsck'd). CTRL+C in the X console seems to
break the halt sometimes, but it can hang again later on. I have tried to leave
the process hanging to see if it would resume processing and sometimes it did
(after waiting several minutes). I havn't seen any hangs in the kernel startup
proper.

The tomsrtbt image do not hang at all. OTOH: It hardly starts any
services...

A+B: UML do not come down cleanly.

When one shuts the UML kernel down the processes on the host are left
running. The problem is the same whatever method you use: uml_mcontrol,
'shutdown -h' from inside the UML kernel or a hard CTRL+C in the host console.
Killing the tracing thread sometimes takes all other process down with it, but
sometimes not.

C: Problems when mounting images (not that important - I tried it out   
   of frustration with the other images)

The boot process stops when the installer tries to mount the /base/stage2.img
image as root. The problem lies in a script called 'rootmnt' or 'mntroot' or
something like that. The actual NFS mount of the installation disks works fine.


Expected Results:  No hanging processes in the startup and no hanging processes
when the UML quits.

Additional info:


Hardware:
    Intel Pentium III
    VIA chipset (VT82C693A/694x, VT82C598/694x, VT82C686)

Software:
    
    Linux version 2.4.18-17.8.0 (bhcompile@daffy.perf.redhat.com) 
    (gcc version 3.2 20020903 (Red Hat Linux 8.0 3.2-7)) #1 Tue Oct 
    8 13:51:08 EDT 2002

    kernel-2.4.18-17.8.0
    kernel-uml-2.4.18-14

Note: In addition to this report I am filing an enhancement request for an UML
image to be included in the distribution for testing purposes. I don't like
filing a bug-report involving modified third party root images, but without an
included image there is no other option.