Go Back   nV News Forums > Linux Support Forums > NVIDIA Linux

Newegg Daily Deals

Reply
 
Thread Tools
Old 02-26-04, 08:36 AM   #1
georg
Registered User
 
Join Date: Jun 2003
Posts: 24
Default Segfault in multi-threaded app when moving windows around

Hello, I'm running the 53.36 drivers on 2.6.3, on a dual xeon machine (hyperthreading on.)

I'm developing a program which runs two threads, each of which makes a windows and a GL context. These happily run some GL (simple drawpixels, GL_LINES, and GL_TRIANGLES stuff) side-by-side. However, when I start moving windows around on the screen, or try dragging e.g. a console over the windows, the program occasionally segfaults. I have not been able to replicate this using only one thread.

run in gdb, i get the following:

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1125342512 (LWP 2405)]
0x40d74e61 in _nv000032gl () from /usr/lib/tls/libGLcore.so.1
(gdb) thread apply all bt

Thread 5 (Thread 1149631792 (LWP 2406)):
#0 0xffffe410 in ?? ()
#1 0x400f884a in _nv000001gl () from /usr/lib/tls/libGL.so.1

Thread 4 (Thread 1125342512 (LWP 2405)):
#0 0x40d74e61 in _nv000032gl () from /usr/lib/tls/libGLcore.so.1

The _nv000032gl bit is variable, but one thread is usually in nv_000001gl and 0xffffe410. Trying to run the program without gdb but with ulimit -c unlimited will reliably lock the machine when the program crashes.

Using the leaked 46.20 drivers, I don't get a segfault; instead, I get a circa 5-second X freeze with 0% cpu use, then the apps carry on as before. This happens far more frequently than the segfaults in 53.36 however. Each time it happens, /var/log/XFree86.0.log says

nvClipLock: client timed out, taking the lock

I cannot replicate this using a single thread, or two applications running a single thread.

This message also appears in 53.36, but only when run in gdb . . .

I don't have any other stability problems with the nvidia drivers.
georg is offline   Reply With Quote
Old 02-26-04, 08:48 AM   #2
zander
NVIDIA Corporation
 
zander's Avatar
 
Join Date: Aug 2002
Posts: 3,740
Default

I can't help you with the OpenGL problem, but the core dump system lockup can be fixed by unconditionally setting the VM_IO flag in vma->vm_flags (nv_kern_mmap, usr/src/nv.c)
zander is offline   Reply With Quote
Old 02-26-04, 09:22 AM   #3
georg
Registered User
 
Join Date: Jun 2003
Posts: 24
Default

Quote:
Originally posted by zander
(...) the core dump system lockup can be fixed by unconditionally setting the VM_IO flag in vma->vm_flags (nv_kern_mmap, usr/src/nv.c)
You're right, that fixes the lock-on-core-dump, thanks.

I was hoping the core files would give some slightly different information to running in gdb, but don't - it seems the segfaults happen the same way.
georg is offline   Reply With Quote
Old 03-01-04, 11:41 AM   #4
georg
Registered User
 
Join Date: Jun 2003
Posts: 24
Default

Update: nvidia say they've already encountered something similar, and hope to have it fixed with the next driver release.
georg is offline   Reply With Quote
Old 03-01-04, 08:59 PM   #5
SnapIT
Registered User
 
Join Date: Jun 2003
Posts: 154
Default

Quote:
Originally posted by georg
Update: nvidia say they've already encountered something similar, and hope to have it fixed with the next driver release.
I have seen similar errors appear in certain implements of OGL, and figured it has to do with the driver implementation of OGL, i have not had time to do a deeper research though, so thanx for confirmation...

The way i see it is that the older implementation of OGL by Nvidia (which has pretty much stayed the same over the last five sets of drivers) contains some ****ty code to begin with (the implement of 2.0 is even worse)...

Eventually Nvidia will get it right, until then i try to stay away from Nvidia when it comes to hardware running OGL...
SnapIT is offline   Reply With Quote
Reply


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


Similar Threads
Thread Thread Starter Forum Replies Last Post
Why Windows 8 could be the next Vista News Archived News Items 0 06-15-12 10:30 AM
Like XP or Vista: how will businesses treat Windows 8? News Archived News Items 0 06-06-12 09:10 AM
Hands-on: Windows 8's SkyDrive News Archived News Items 0 06-04-12 07:30 PM
NVIDIA Brings 18 Years of Experience to Windows 8 News Archived News Items 0 06-03-12 06:20 AM
Sync it up: Hands on with the preview of Windows 8's cloud sync service News Archived News Items 0 06-02-12 08:30 PM

All times are GMT -5. The time now is 12:01 AM.


Powered by vBulletin® Version 3.7.1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 1998 - 2014, nV News.