Similar topic I found (but without answers): viewtopic.php?f=225&t=109219

Since yesterday, native KDE applications and a few others will no longer start in KDE. What I've tried: clearing /var/tmp/kdecache-*. This is on KDE 4.11.1, Arch Linux. More details I thought might be relevant are here: http://paste.kde.org/p521d00a5/ (some example outputs when launching programs, .xsession-errors, list of recently changed packages)

Any ideas what might be causing this or how to find out?

Hi,

no immediate ideas, just what I'd do:

Run the application from konsole. Is there any relevant output?

Run the application from konsole in gdb, wait a few seconds and press Ctrl+C, then get the backtrace via "bt". Is there anything useful in there?

Run the application in strace, e.g. run strace -f kwrite in konsole. There will be a lot of output; is there anything repeating in the end when it hangs?

If you need help in interpreting the output, please post it here.

Cheers,
Sven

Thanks for the swift reply! However, I am hopefully unknowledgeable in dealing with these backtraces, since I'm not really familiar with the structure of KDE programs. I would be very thankful if you could give me some pointers.

Here are some of the outputs you mentioned for kwrite (the output when running it straight from the console is empty):

(gdb) bt

Code: Select all

#0  0x00007ffff78f49f0 in __read_nocancel () from /usr/lib/libc.so.6
#1  0x00000035d7a0883f in ?? () from /usr/lib/libICE.so.6
#2  0x00000035d7a0d510 in _IceRead () from /usr/lib/libICE.so.6
#3  0x00000035d7a116e1 in IceProcessMessages () from /usr/lib/libICE.so.6
#4  0x00000035d7a06121 in IceOpenConnection () from /usr/lib/libICE.so.6
#5  0x00007ffff2d91f00 in SmcOpenConnection () from /usr/lib/libSM.so.6
#6  0x00007ffff5bc89f5 in QSessionManager::QSessionManager(QApplication*, QString&, QString&) () from /usr/lib/libQtGui.so.4
#7  0x00007ffff5b64b43 in QApplicationPrivate::initialize() () from /usr/lib/libQtGui.so.4
#8  0x00007ffff5b64cd2 in QApplicationPrivate::construct(_XDisplay*, unsigned long, unsigned long) () from /usr/lib/libQtGui.so.4
#9  0x00007ffff5b65069 in QApplication::QApplication(int&, char**, bool, int) () from /usr/lib/libQtGui.so.4
#10 0x00007ffff68820d8 in KApplication::KApplication(bool) () from /usr/lib/libkdeui.so.5
#11 0x00007ffff7bd7bd8 in ?? () from /usr/lib/libkdeinit4_kwrite.so
#12 0x00007ffff7bd651e in kdemain () from /usr/lib/libkdeinit4_kwrite.so
#13 0x00007ffff783dbc5 in __libc_start_main () from /usr/lib/libc.so.6
#14 0x0000000000400731 in _start ()


last few lines before strace -f kwrite hangs:

Code: Select all

writev(6, [{"\203\2\1\0", 4}, {NULL, 0}, {"", 0}], 3) = 4
poll([{fd=6, events=POLLIN}], 1, 4294967295) = 1 ([{fd=6, revents=POLLIN}])
recvfrom(6, "\1\2m\1\230\0\0\0\f\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 4096, 0, NULL, NULL) = 640
recvfrom(6, 0x6a19c4, 4096, 0, 0, 0)    = -1 EAGAIN (Resource temporarily unavailable)
recvfrom(6, 0x6a19c4, 4096, 0, 0, 0)    = -1 EAGAIN (Resource temporarily unavailable)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 8
fstat(8, {st_mode=S_IFREG|0644, st_size=268284, ...}) = 0
mmap(NULL, 268284, PROT_READ, MAP_PRIVATE, 8, 0) = 0x7fdaca18a000
close(8)                                = 0
open("/usr/lib/libwacomcfg.so.0", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
munmap(0x7fdaca18a000, 268284)          = 0
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 8
fstat(8, {st_mode=S_IFREG|0644, st_size=268284, ...}) = 0
mmap(NULL, 268284, PROT_READ, MAP_PRIVATE, 8, 0) = 0x7fdaca18a000
close(8)                                = 0
open("/usr/lib/libwacomcfg", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
munmap(0x7fdaca18a000, 268284)          = 0
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 8
fstat(8, {st_mode=S_IFREG|0644, st_size=268284, ...}) = 0
mmap(NULL, 268284, PROT_READ, MAP_PRIVATE, 8, 0) = 0x7fdaca18a000
close(8)                                = 0
open("/usr/lib/wacomcfg.so.0", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
munmap(0x7fdaca18a000, 268284)          = 0
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 8
fstat(8, {st_mode=S_IFREG|0644, st_size=268284, ...}) = 0
mmap(NULL, 268284, PROT_READ, MAP_PRIVATE, 8, 0) = 0x7fdaca18a000
close(8)                                = 0
open("/usr/lib/wacomcfg", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
munmap(0x7fdaca18a000, 268284)          = 0
socket(PF_LOCAL, SOCK_STREAM, 0)        = 8
uname({sys="Linux", node="mueslimobil", ...}) = 0
connect(8, {sa_family=AF_LOCAL, sun_path=@"/tmp/.ICE-unix/1275"}, 22) = 0
fcntl(8, F_SETFD, FD_CLOEXEC)           = 0
write(8, "\0\1\0\0\0\0\0\0", 8)         = 8
read(8, ^CProcess 26825 detached
 <detached ...>


recvfrom(6, 0x6a19c4, 4096, 0, 0, 0) = -1 EAGAIN (Resource temporarily unavailable)

this part repeats a few times before it as well.

Thank you very much for your time!

Hm, this looks quite meaningful, but still I unfortunately can't deduce much tips for fixing it from it
Hopefully someone else comes across this thread who is more knowledgeable about this ICE stuff...
I assume restarting X11 doesn't fix the issue? Does it work for a different user account?

Cheers,
Sven

did you just do an upgrade of KDE

run: kbuildsycoca4 --noincremental 2> /dev/null

if things are also bad for a new user I'd reinstall KDE

scummos wrote:I assume restarting X11 doesn't fix the issue? Does it work for a different user account?

Restarting doesn't fix it. For other users, see below:

google01103 wrote:did you just do an upgrade of KDE

run: kbuildsycoca4 --noincremental 2> /dev/null

if things are also bad for a new user I'd reinstall KDE

I did do an upgrade from 4.10.5 to 4.11.1 about a week ago (though I'm not sure if I restarted X between that session and before I noticed it). kbuildsycoca doesn't change anything.

It also doesn't work for some older user (whose configuration files haven't been touched in about a year. However, a brand new user works, so it would seem to me that it is related to configuration files. Indeed, renaming .kde4/ lets it work again for my current user, but having to reconfigure everything would be a pain. Any ideas what configuration in .kde4/ could lead to something like this?

I can't confirm that it was due to 4.10.5. -> 4.11.1 because I ran out of space in / a few days ago so I cleaned up my package cache (which in retrospect was pretty stupid), so I can't currently roll back easily.

there's 3 groups of config files I'd move/rename in $KDEHOME/share/config, obviously this will cause things to revert to default values

1) move all kde* files then restart KDE
2) plasma, backup and reset to default:

Code: Select all

kquitapp plasma-desktop
 sleep 20s
 mkdir -p $HOME/plasma-config/
 mv $(kde4-config --localprefix)/share/config/plasma-desktop* $HOME/plasma-config/
plasma-desktop &

3) move all kwin* files then run:

Code: Select all

kwin --replace

google01103 wrote:there's 3 groups of config files I'd move/rename in $KDEHOME/share/config, obviously this will cause things to revert to default values

1) move all kde* files then restart KDE

Same behaviour as before (i.e. still can't launch anything, and no change apart from fonts and visual styles)

google01103 wrote:2) plasma, backup and reset to default:

Code: Select all

kquitapp plasma-desktop
 sleep 20s
 mkdir -p $HOME/plasma-config/
 mv $(kde4-config --localprefix)/share/config/plasma-desktop* $HOME/plasma-config/
plasma-desktop &

plasma-desktop fails, due to "QDBusConnection: session D-Bus connection created before QCoreApplication. Application may misbehave."
If I restart kdm with those config files moved, it still doesn't work.

google01103 wrote:3) move all kwin* files then run:

Code: Select all

kwin --replace

Nothing happens when I run that (also can't ctrl-c), also outputs "QDBusConnection: session D-Bus connection created before QCoreApplication. Application may misbehave."
Restarting kdm with those files moved also doesn't change anything.

think the D-Bus message isn't important

all I can think of is renaming various chunks of ~/.kde and then restarting KDE starting with the the share/config folder and if that fixes it I'd bring back 1/2 the files at a time and restart until I could id the bad file(s)

maybe someone else will have a better idea

Random guess from the backtrace: Try disabling session management...

Please try removing /tmp/.ICE-unix and /tmp/.X11-unix, with no X processes running.

bcooksley wrote:Please try removing /tmp/.ICE-unix and /tmp/.X11-unix, with no X processes running.

Thanks, but it's too late, it's started working again. What I did prior to it working agian was test individual components of .kde4/, and suddenly after adding them all again it started to work again.