Re: F10 - pulseaudio not running



Rex Dieter wrote:
ConsoleKit uses acl's to set premissions for console devices (like audio).
At least, it's *supposed* to.


and Kevin Kofler wrote:
... except your local console user, which gets the permissions using the
POSIX ACL feature.
... The '+' here means some ACLs are set. Try:
getfacl /dev/snd/*

PulseAudio is only SUID root to allow it to use real-time priority for users
in the pulsert group or with real-time priority allowed through PolicyKit.
It does not use the root privileges to access sound devices, it accesses
them as your regular user.


I can see that on my functioning desktops that before login, gdm has
been granted read-write access, via ACLs, to the sound device files in
/dev/snd/. After GDM login my user is granted read-write instead.

On my broken desktop there are no ACLs granting extra permissions. I
have now restored the original permissions on the /dev/snd/* files and
added my user read-write access via ACLs. Still pulseaudio does not
start.

I also noticed that on my broken desktop, console-kit-daemon is not
running. So far I have only found that console-kit-daemon may have
been started with /etc/rc.d/init.d/ConsoleKit circa Fedora 8. That
consoleKit service script been removed in Fedora 10 and I don't yet
know how console-kit-daemon is meant to be started.

Is console-kit-daemon running even relevant to GDM adding ACLs for the
console user to access devices? Probably. Is this relevant to why
pulseaudio fails to start? Don't know as even when standard file
permissions, rather than ACLs, allowed access to /dev/snd/* pulseaudio
died on startup.

From my functional home desktop ...
[mike@rockover ~]$ getfacl -p /dev/snd/controlC0
# file: /dev/snd/controlC0
# owner: root
# group: root
user::rw-
user:mike:rw-
group::rw-
mask::rw-
other::---
(Same results of additional user mike ACL for all devices in /dev/snd/).
[mike@rockover ~]$ ck-list-sessions
Session4:
unix-user = '500'
realname = 'Mike Fleetwood,,,,'
seat = 'Seat1'
session-type = ''
active = TRUE
x11-display = ':0'
x11-display-device = '/dev/tty1'
display-device = ''
remote-host-name = ''
is-local = TRUE
on-since = '2009-04-08T19:06:01.429138Z'
login-session-id = '702'
[mike@rockover ~]$ ps -ef | fgrep console-kit-daemon
root 2477 1 0 Apr08 ? 00:00:00 /usr/sbin/console-kit-daemon
mike 23954 19225 0 12:05 pts/0 00:00:00 fgrep console-kit-daemon

From my broken work desktop ...
[mfleetwo@mfleetwo3 ~]$ su -
Password:
[root@mfleetwo3 ~]# chmod o= /dev/snd/*
[root@mfleetwo3 ~]# setfacl -m u:mfleetwo:rw /dev/snd/*
[root@mfleetwo3 ~]# ls -l /dev/snd/*
crw-rw----+ 1 root root 116, 7 2009-04-22 13:13 /dev/snd/controlC0
crw-rw----+ 1 root root 116, 6 2009-04-22 13:13 /dev/snd/hwC0D0
crw-rw----+ 1 root root 116, 5 2009-05-06 12:15 /dev/snd/pcmC0D0c
crw-rw----+ 1 root root 116, 4 2009-05-06 12:15 /dev/snd/pcmC0D0p
crw-rw----+ 1 root root 116, 3 2009-04-22 13:13 /dev/snd/seq
crw-rw----+ 1 root root 116, 2 2009-04-22 13:13 /dev/snd/timer
[root@mfleetwo3 ~]# getfacl -p /dev/snd/controlC0
# file: /dev/snd/controlC0
# owner: root
# group: root
user::rw-
user:mfleetwo:rw-
group::rw-
mask::rw-
other::---
[root@mfleetwo3 ~]# exit
logout
[mfleetwo@mfleetwo3 ~]$ pulseaudio --start --log-target=syslog
I: caps.c: Limited capabilities successfully to CAP_SYS_NICE.
I: caps.c: Dropping root privileges.
I: caps.c: Limited capabilities successfully to CAP_SYS_NICE.
[WARN 9224] polkit-session.c:144:polkit_session_set_uid(): session != NULL
Not built with -rdynamic so unable to print a backtrace
[mfleetwo@mfleetwo3 ~]$ echo $?
1
[mfleetwo@mfleetwo3 ~]$ ps -ef | fgrep pulseaudio
[mfleetwo@mfleetwo3 ~]$ ck-list-sessions

** (ck-list-sessions:9244): WARNING **: Failed to get list of seats:
Cannot launch daemon, file not found or permissions invalid
[mfleetwo@mfleetwo3 ~]$ ps -ef | fgrep console-kit-daemon


Thanks,
Mike

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