[CentOS] My linux keeps logging me off when I run Firefox (how to debug)?

Mon Apr 15 23:07:46 UTC 2013
Fred Smith <fredex at fcshome.stoneham.ma.us>

On Mon, Apr 15, 2013 at 07:29:05PM +0000, Rock wrote:
> This is a strange one to me.
> Just recently, my Centos 6 has been "gentle crashing" where it doesn't crash, 
> per se, but the screen goes black, and the login prompt pops up. 
> It only happens when I run Firefox and it only started happening this morning.
> However, it has happened a dozen times, and always when Firefox is running.
> It does NOT happen when Firefox is not running. 
> I haven't tested with Chrome yet; so that's my next test - but - the 
> question I have is:
> How do I log the events that are causing Centos to log me out of 
> user1 and to present the login screen?

Do you have an NVIDIA graphics card?

if yes, are you using the driver package directly from NVIDIA (as
opposed to onoe of the RPM versions from, e.g., epel, or wherever...

I've had what you describe happen to me under those circumstances.
The nvidia drivers replace some system library, and now and then
(not too often, in my experience, in fact pretty rarely) that system
lib gets updated, threby trashing the Nvidia replacement.

When that happens, firing up firefox will kill X, dropping you back
to the login.

if that sounds like what you see, just go rerun the nvidia installer,
then you should be working again.

---- Fred Smith -- fredex at fcshome.stoneham.ma.us ----------------------------
                    Do you not know? Have you not heard? 
    The LORD is the everlasting God, the Creator of the ends of the earth. 
  He will not grow tired or weary, and his understanding no one can fathom.
----------------------------- Isaiah 40:28 (niv) -----------------------------