Bug 767861

Can you give me a strace in order to find out what lxdm is doing?

2 cycles:

poll([{fd=6, events=POLLIN}, {fd=7, events=POLLIN}, {fd=4, events=POLLIN}], 3, -1) = 1 ([{fd=6, revents=POLLIN}])
read(6, "\2\0\0\0\0\0\0\0", 16)         = 8
write(6, "\1\0\0\0\0\0\0\0", 8)         = 8
recvmsg(4, 0x7fff81171130, 0)           = -1 EAGAIN (Resource temporarily unavailable)
write(6, "\1\0\0\0\0\0\0\0", 8)         = 8
poll([{fd=6, events=POLLIN}, {fd=7, events=POLLIN}, {fd=4, events=POLLIN}], 3, -1) = 1 ([{fd=6, revents=POLLIN}])
read(6, "\2\0\0\0\0\0\0\0", 16)         = 8
write(6, "\1\0\0\0\0\0\0\0", 8)         = 8
recvmsg(4, 0x7fff81171130, 0)           = -1 EAGAIN (Resource temporarily unavailable)
write(6, "\1\0\0\0\0\0\0\0", 8)         = 8

I'm still seeing this with lxdm-0.3.0-6.fc17 (i686).

100% cpu likely a bug in lxdm, appeared in f17 because of new version of glib,
have been fixed in upstream.

I found a patch in ubuntu package that fixes this issue for me. I got a patch from following package that called 90_fix_event_check.patch.
https://launchpad.net/ubuntu/+source/lxdm/0.4.1-0ubuntu5

This patch changes lxcom_check()'s return value.
 static gboolean lxcom_check(GSource *source)
 {
-       return TRUE;
+       return (((LXComSource*)source)->poll.revents&G_IO_IN)?TRUE:FALSE;
 }

That patch is from http://lxde.git.sourceforge.net/git/gitweb.cgi?p=lxde/lxdm;a=commit;h=d4e41ecb and I have it in my package, too. However I now have two problems with LXDM 0.4.1:
1. It's not switching VTs, this means the computer boots up and LXDM is starting on VT7, but display keeps showing vt1 with a blinking cursor.
2. Sometimes LXDM is not starting.

If this both works for you, can you show me your lxdm.conf?

I made lxdm 0.4.1 package for myself ant tested it.

>1. It's not switching VTs, this means the computer boots up and LXDM is
starting on VT7, but display keeps showing vt1 with a blinking cursor.
I have same issue too.

>2. Sometimes LXDM is not starting.
I checked(reboot and login) 12-15 times but I didn't reproduce it.

Anyway, this is my lxdm.conf. 
[base]
## uncomment and set autologin username to enable autologin
# autologin=dgod

## uncomment and set timeout to enable timeout autologin,
## the value should >=5
# timeout=10

## default session or desktop used when no systemwide config
# session=/usr/bin/startlxde

## uncomment and set to set numlock on your keyboard
# numlock=0

## set this if you don't want to put xauth file at ~/.Xauthority
# xauth_path=/tmp

## greeter used to welcome the user
greeter=/usr/libexec/lxdm-greeter-gtk

[server]
## arg used to start xserver, not fully function
# arg=/usr/bin/X -background vt1

[display]
## gtk theme used by greeter
gtk_theme=Clearlooks

## background of the greeter
bg=/usr/share/backgrounds/default.png

## if show bottom pane
bottom_pane=1

## if show language select control
lang=1

## if show keyboard layout select control
keyboard=0

## the theme of greeter
theme=Industrial

[input]

[userlist]
## if disable the user list control at greeter
disable=0

## whitelist user
white=

## blacklist user
black=

If I uncomment "# arg=/usr/bin/X -background vt1" line, lxdm works as f16 does.
Fedora 16's lxde.conf is uncommented this line.

[server]
## arg used to start xserver, not fully function
# arg=/usr/bin/X -background vt1

fedara 16 and 17 use these VTs.  
vt1:lxde
vt2:console
vt3:console 
vt4:console
vt5:console
vt6:console
vt7:cursor is blinking

I checked lxdm latest source[1], and 0.4.1 that is release version.

[1]http://lxde.git.sourceforge.net/git/gitweb.cgi?p=lxde/lxdm;a=tree;h=43a30962ac7a68ddef8eed8900153049ceba3340;hb=8c71ffc87305a5742d3ed9f98134cee31117ddd3)

lxdm-0.4.1-1.fc17 has been submitted as an update for Fedora 17.
https://admin.fedoraproject.org/updates/lxdm-0.4.1-1.fc17

lxdm-0.4.1-1.fc16 has been submitted as an update for Fedora 16.
https://admin.fedoraproject.org/updates/lxdm-0.4.1-1.fc16

lxdm-0.4.1-1.fc15 has been submitted as an update for Fedora 15.
https://admin.fedoraproject.org/updates/lxdm-0.4.1-1.fc15

Package lxdm-0.4.1-1.fc16:
* should fix your issue,
* was pushed to the Fedora 16 testing repository,
* should be available at your local mirror within two days.
Update it with:
# su -c 'yum update --enablerepo=updates-testing lxdm-0.4.1-1.fc16'
as soon as you are able to.
Please go to the following url:
https://admin.fedoraproject.org/updates/FEDORA-2012-4399/lxdm-0.4.1-1.fc16
then log in and leave karma (feedback).

lxdm-0.4.1-1.fc17 has been pushed to the Fedora 17 stable repository.  If problems still persist, please make note of it in this bug report.

lxdm-0.4.1-1.fc15 has been pushed to the Fedora 15 stable repository.  If problems still persist, please make note of it in this bug report.

lxdm-0.4.1-1.fc16 has been pushed to the Fedora 16 stable repository.  If problems still persist, please make note of it in this bug report.