On Mon, 29 Aug 2011 21:06:29 +0200
Roberto Ragusa <mail(a)robertoragusa.it> wrote:
Hi,
it sometimes happens to me that X completely locks up, while the
machine is still alive on the network.
This is on F14, untainted kernel, nouveau driver, no 3D used,
KDE desktop on a 32-bit machine with 8GiB RAM and PAE kernel.
It typically happens when something is going to be drawn on
the screen (a window pops up or virtual desktop change).
I would like to open a bug, but I'm not able to attach any kind
of usable log; dmesg says nothing, all I can say is that
the screen remains frozen (including the pointer), the X
server and the kernel keep doing some "SIG ALRM" stuff and
any attempt to access the X server stalls the command (xrandr
or xset, for example), in a Ctrl-C responsive way.
Any idea?
I had this problem in F14 while using the stock kernel. When I
compiled a custom kernel it went away. While I made *many* changes, I
think the one that mattered was turning off SMP on my single core
system. I suspect, without proof, that the SMP code was occasionally
causing a race condition, and a deadlock. Other possible causes for
fix: moved to pre-emptable desktop, reserved 128 K low memory for
kernel, moved to deadline scheduler.
You could open a bug against the kernel, but it has moved on so far
that it will probably languish.