Re: [Announce] 2.6.29-rc8-rt2

[Ingo Molnar <mingo@elte.hu>]

* Fernando Lopez-Lezcano <nando@ccrma.Stanford.EDU> wrote:

> On Sun, 2009-03-22 at 14:09 +0100, Ingo Molnar wrote:
> > * Fernando Lopez-Lezcano <nando@ccrma.Stanford.EDU> wrote:
> > 
> > > On Sat, 2009-03-21 at 12:27 -0700, Fernando Lopez-Lezcano wrote:
> > > > On Sat, 2009-03-21 at 12:06 -0700, Fernando Lopez-Lezcano wrote:
> > > > > On Sat, 2009-03-21 at 19:49 +0100, Ingo Molnar wrote:
> > > > > > * Fernando Lopez-Lezcano <nando@ccrma.Stanford.EDU> wrote:
> > > > > > 
> > > > > > > Mar 21 10:47:43 localhost kernel: kernel tried to execute NX-protected
> > > > > > > page - exploit attempt? (uid: 0)
> > > > > > > Mar 21 10:47:43 localhost kernel: BUG: unable to handle kernel paging
> > > > > > > request at f6400800
> > > > > > 
> > > > > > kernel tried to execute some really weird address, probably via a 
> > > > > > function pointer.
> > > > > 
> > > > > Strangely enough rc8-rt1 boots (almost). _Exact_ same build with the
> > > > > exception of the change from rt1 -> rt2. 
> > > > > 
> > > > > Haldaemon does not start on boot (fails), if I login as root and start
> > > > > the haldaemon service manually it starts. And then things seem to work
> > > > > fine (I'm writing this email from that machine). Still investigating...
> > > > 
> > > > First problem was due to old firmware for the iwl3945 hardware. I
> > > > updated to the latest and hal started fine (this is on fc9). 
> > > > 
> > > > Now another one related to xorg/drm...
> > > 
> > > Scratch that, I had an old version of xorg/drm installed in this 
> > > particular machine and the new kernel did not like it. Seems to 
> > > boot fine now... sorry for the noise.
> > 
> > No problem :-)
> > 
> > I'm wondering, do you have any theory about how the old firmware 
> > cause that weird NX-fault kernel crash? For a few minutes i took it 
> > for an x86 crash.
> 
> Sorry, no theories at all - I would have to be a kernel guru for that. I
> was surprised the whole thing went away with the firmware upgrade (I saw
> some message in /var/log/messages telling me the firmware was old) - it
> did seem like something more serious. 
> 
> I hit another problem. On a quad code intel machine here at home there
> is a problem during shutdown. The final shutdown dies with a traceback
> (something like "rc0 was killed by SIGSEGV" or similar words at the very
> end). Then I have to push the power button for x+ seconds to force a
> power off. 
> 
> Should I post a picture of the screen as it is at that point, or just
> send that to you and Thomas? 

any kernel stack dump in that?

You could try to do this before shutting down:

  echo 1 > /proc/sys/kernel/print-fatal-signals
  dmesg -n 8

that way there's a (hopefully helpful) stack dump done of the 
SIGSEGV itself.

	Ingo