It was Intel GPU driver issue. I have to upgraded to Ubuntu 14.10, because Intel has deprecated their driver for 14.04.

Upgrage to 14.10, and install their latest gpu driver, then issue disappeared.

Interesting thing is, the sudden logout happened only when I'm using Pd. Strange.

Thanks for the clew Claude!

https://01.org/linuxgraphics/downloads/2015/intelr-graphics-installer-linux-1.0.8

Issue resolved.

Many thanks,

Jonghyun Kim

On Thu, Mar 19, 2015 at 10:46 PM, Jonghyun Kim <agitato816@gmail.com> wrote:

thanks for the info. 

Intel HD 4000 graphics driver causes this problem?, however why crash only when I'm using Pd...? strange...

many thanks,

akntk 

On Thu, Mar 19, 2015 at 9:53 PM, Claude Heiland-Allen <claude@mathr.co.uk> wrote:

Looks like possibly the same driver issue as

http://forum.pdpatchrepo.info/topic/7614/solved-pd-crashes-x-server

On 19/03/15 12:41, Jonghyun Kim wrote:

FYI, I had same problem before with Pd-0.45-4-1 (downloaded from Ubuntu
software center)

On Thu, Mar 19, 2015 at 9:36 PM, Jonghyun Kim <agitato816@gmail.com> wrote:

hi list,

i have strange behavior using Pd.

When I do some patching in Pd, Ubuntu suddenly logouts, and I loss my
current data.

I don't know what causes this problem.

Strange thins is, this unexpected sudden logout occurs only when I'm using
Pd. Another application doesn't occur this problem.

I attached the Pd patch.

thanks,
akntk
====================

Software:
Pd-0.46-5 (from miller's home page) build from source

Ubuntu 14.04 amd64
Linux umi 3.13.0-46-generic #79-Ubuntu SMP Tue Mar 10 20:06:50 UTC 2015
x86_64 x86_64 x86_64 GNU/Linux

Video Card: Intel HD
akntk@umi:~$ lspci -v -s `lspci | awk '/VGA/{print $1}'`
00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core
processor Graphics Controller (rev 09) (prog-if 00 [VGA controller])
Subsystem: Lenovo Device 21f6
Flags: bus master, fast devsel, latency 0, IRQ 45
Memory at f0000000 (64-bit, non-prefetchable) [size=4M]
Memory at e0000000 (64-bit, prefetchable) [size=256M]
I/O ports at 5000 [size=64]
Expansion ROM at <unassigned> [disabled]
Capabilities: <access denied>
Kernel driver in use: i915

=====================

Download link of the Pd patch:

https://drive.google.com/folderview?id=0B42bn7ncw918fkVFR0JYVHNsbVh5VzVFaHBXUWlTdGV6YzRtWGhFS0h5ODFOZ0RISU5Bd3c&usp=sharing

_______________________________________________
Pd-list@lists.iem.at mailing list
UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list

_______________________________________________
Pd-list@lists.iem.at mailing list
UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list