Help! Gnome-Shell segfault.

[Rich Boyce]

On 15/12/11 16:08, Arthur Dent wrote:
> On Wed, 2011-12-14 at 14:11 +0000, Rich Boyce wrote:
>> On 14/12/11 12:54, Arthur Dent wrote:
>>>> On 14/12/11 09:18, Arthur Dent wrote:
>>>>>> Hello all,
>>>>>>
>>>>>> Urgent help required!
>>>>>>
>>>>>> I have turned on my Fedora 16 machine today. It booted quite normally
>>>>>> to
>>>>>> the
>>>>>> GDM login screen. When I selected one of my 3 users it started to login
>>>>>> to
>>>>>> the account as usual, but got no further than loading the background. I
>>>>>> CTRL-ALT-BKSPC'd back to the login screen and tried each of the other
>>>>>> accounts. Same problem. I can start a terminal session with CTRL-ALT-F2
>>>>>> and login to any user account in that terminal - and it is from there
>>>>>> that
>>>>>> I am sending this (using Mutt). I have tried googling using a text
>>>>>> based
>>>>>> browser, (but that is quite hard work) and all I have come up with is
>>>>>> this
>>>>>> bugzilla https://bugzilla.redhat.com/show_bug.cgi?id=753666 which
>>>>>> describes my symptoms perfectly (I am also using the nvidia akmod
>>>>>> driver)
>>>>>> but there is no resolution for me in that bugzilla.
>>>>>>
>>>>>> Unlike that report I have updated nothing since Sunday (11 December)
>>>>>> and
>>>>>> it
>>>>>> worked fine yesterday (12 December). Here is an extract from dmesg:
>>>>>>
>>>>>> [   39.204161] gnome-shell[1458]: segfault at bc955315 ip 42325db4 sp
>>>>>> bfadd520
>>>>>> error 6 in ld-2.14.90.so[42319000+21000]
>>>>>>
>>>>>> Below I list a (long) extract form /var/log/messages. There is some
>>>>>> very
>>>>>> fishy
>>>>>> looking stuff in that, but I have no idea how to fix it. Please help me
>>>>>> to
>>>>>> get
>>>>>> back to a working gnome-shell!
>>>>>>
>>>>>> Thanks
>>>>>>
>>>>>> Mark
>>>>>
>>>>> I don't wish to appear desperate - but...
>>>>>
>>>>> ...I am desperate!
>>>>>
>>>>> Any ideas?
>>>>
>>>> It's a bit of a shot in the dark, but you could try removing the
>>>> proprietary nvidia drivers, and rebooting. It would be something like
>>>>
>>>> yum erase \*kmod\*nvidia xorg-x11-drv-nvidia\*
>>>>
>>>> That would probably get you back to the nouveau drivers.
>>>>
>>>> If that doesn't work, there might be a hint in your /var/log/Xorg.0.log
>>>>
>>>> Rich
>>>
>>> Well thanks for that. I was actually thinking about removing the nvidia
>>> driver.
>>>
>>> As it happens, I gave up on the machine for the moment and went to work. I
>>> therefore no longer have physical access to the machine. I can, however
>>> ssh into it. While I was wondering about removing or re-installing the
>>> nvidia driver I noticed that there is a new kernel available in yum
>>> (3.1.5-1.fc16.i686.PAE) so I did a yum update. This will of course cause
>>> the akmod module to rebuild the driver.
>>>
>>> I have rebooted, and the encouraging thing is that dmesg now has no
>>> reference to a gnome-shell segfault!
>>
>> Well that's very encouraging!
>>
>>> Unfortunately I will not be home again until Thursday evening so I can't
>>> actually try to log in to gnome-shell to see if it has worked (are there
>>> any command line tricks to test if gnome-shell is working?).
>>
>> Hmm. You could run 'ps fax' and look for a gnome-shell process, or a gdm
>> process (I'm not sure what the login manager shows up as). If you see it
>> there, that shows that it's running.
>
> Well I got home today earlier than expected. That's the good news. The
> bad news is that, when I turned on the machine, another segfault is
> reported in dmesg and I am still locked out of gnome-shell.

Boo!

> Soooo... I uninstalled the nvidia driver and reverted back to the
> nouveau one.
>
> Now I am typing this to you from Evolution using gnome 3. In other words
> I am back in.

Great! So we've established that it is the nvidia driver that's causing 
the problem.

> To tell you the truth I have not noticed any real difference between the
> nvidia and the nouveau drivers. I guess I should just stay with nouveau.
> Is there anything I should be aware of while using nouveau instead of
> the proprietary nvidia driver?

Well, the graphics acceleration is poorer with nouveau, and there might 
be some stability issues I suppose, I haven't used nouveau for a long 
time as the proprietary driver has always worked for me. On the other 
hand, you get the self-satisfaction of using open-source software.

> Is it worth persisting with nvidia?

Only if you need it. If nouveau gives you all the accelerated graphics 
you need, stick with it.

> Thanks for all the help...

No problem.

Rich