Possible radeon-related kernel memory leak

[Hubert Kario]

On Wednesday 13 of February 2013 11:51:00 Michel Dänzer wrote:
> On Die, 2013-02-12 at 22:54 +0100, Hubert Kario wrote:
> > On Monday 11 of February 2013 13:00:41 Michel Dänzer wrote:
> > > On Son, 2013-02-10 at 15:01 +0100, Hubert Kario wrote:
> > > > > > Even if I turn off all applications and restart kwin, it's still
> > > > > > at
> > > > > > 1G.
> > > > > 
> > > > > xlsclients only lists kwin at that point, no other clients?
> > > > 
> > > > no, there's still the plasma desktop, krunner, probably something
> > > > else...
> > > 
> > > Have you tried killing those?
> > 
> > If I have the problem next time, I'll try restarting or killing
> > everything that shows up in xlsclients
> > 
> > Is there any specific data you want to see before and after killing
> > those
> > applications? And before and after killing X (without system restart) if
> > restarting X clients doesn't resolve the issue?
> 
> Not sure offhand what to look at other than the numbers you've posted.
> 
> But really, if the memory is reclaimed when X dies, by definition it's
> not leaked in the kernel.

It depends on how you define leaked.

In this case I define "leak" as memory that can't be used actively by kernel 
or userspace, not necessarily memory we don't have references for.

While it's not technically a leak, it has all the side effects of a real 
leak.

> > > > Do you think it's not related to the errors I get sometimes while
> > > > running
> > > > games?
> > > > 
> > > > radeon: The kernel rejected CS, see dmesg for more information
> > > > 
> > > > with the following error in dmesg (full kernel stack trace in first
> > > > mail
> > > > in thread):
> > > > 
> > > > [drm:radeon_cs_ioctl] ERROR Failed to parse relocation -12
> > > > 
> > > > Can't this cause leaks of kernel memory that are freed only on full
> > > > X
> > > > re-
> > > > initialisation?
> > > 
> > > These errors are symptoms of running out of kernel memory, probably
> > > not
> > > the cause of it.
> > 
> > Thing is, when I'm playing the game in question I turn off everything
> > besides the KDE services and background daemons, so I have close to
> > 3.5GiB of free memory.
> 
> You could be running into
> https://bugzilla.kernel.org/show_bug.cgi?id=49981

This very much looks like it. Now, should I go and compile mesa from git or 
still try to reach 1G of noncache kernel dynamic memory (I'm at  800M)...

Ehh, decisions, decisions... :)

Regards,
-- 
Hubert Kario