Bug#425397: tasksel/pkgsel causing Etch netboot install to hang indefinitely

[abridgett@smop.co.uk (Adrian Bridgett)]

I've hit this exact issue (nice workaround with the "echo" trick) and
been doing some more debug.   With _loads_ of debug the bug
dissappeared :-(   But I have now managed to see where the race is.

When the hang occurs, the last few things that debconf does (booted
with "install DEBCONF_DEBUG=5" with additional "warn" stuck in:
(I can see dpkg-preconfigure calling "make_frontend()")
read "PROGRESS SET 18"
send "0 OK"
read "CAPB"
send "0 multiselect escape multiselect backup progresscancel"
recv "SUBST debconf-apt-progress/info DESCRIPTION Retrieving file 84 of 84"
send "0"   (no OK FWIW)
recv "PROGRESS INFO deconf-apt-progress/info"
send "0 OK"
(hang occurs)


With more debug, it didn't hang, but have a look at the message
received this time:
read "PROGRESS SET 18"
send "0 OK"

recv "SUBST debconf-apt-progress/info DESCRIPTION Retrieving file 84 of 84"
send "0"   (no OK FWIW)
recv "PROGRESS INFO deconf-apt-progress/info"
send "0 OK"
(
  I can see dpkg-preconfigure calling "make_frontend()"
  ...
  calls Debconf::FrontEnd::Passthrough->new()
)
read "CAPB"
send "0 multiselect escape multiselect backup progresscancel"
read "TITLE"
...


So the hang occurs when dpkg-preconfigure calls make_frontend _before_
the last PROGRESS_INFO has occured).

I think I'd better leave this to the Debconf guru's now :-)

I have more logs available if they are any help (I suspect not).   I
was doing a CD based install with desktop package deselected (just base
system package selected).

Adrian