system sporadically hangs on shutdown after switching to WITH_NEW_XORG

[Michiel Boland]

On 06/16/2013 17:37, Konstantin Belousov wrote:
> On Sun, Jun 16, 2013 at 05:11:15PM +0200, Michiel Boland wrote:
>> Hi. Recently I switched to WITH_NEW_XORG, primarily because the stock X server
>> with Intel driver has some issues that make it unusable for me.
>>
>> The new X server and Intel driver works extremely well, so kudos to whoever made
>> this possible.
>>
>> Unfortunately, I am now experiencing random hangs on shutdown. On shutdown the
>> system randomly freezes after
>>
>> [...] syslogd: exiting on signal 15
>>
>> I would then expect to see 'Waiting (max 60 seconds) for system process 'XXX' to
>> stop messages, but these never arrive.
>>
>> I paniced the machine in ddb, so I have a crash dump if someone want to look at
>> it. The crashinfo is at http://barrytown.boland.org/core.txt (I would have
>> pasted it here but it is a bit verbose.)
>>
>> Machine has an Intel G41 chipset, with a SAMSUNG SSD 830 Series HD, running
>> 9.1-STABLE r251803. Serial console. GENERIC kernel, expect for options DDB and
>> ALT_BREAK_TO_DEBUGGER.
>>
>> Who knows what's going on here?
>
> I do not see anything related to i915 in the core.txt you provided.
>
> Next time the machine hangs, start with the output of ps command from
> ddb and 'show allpcpu', together with 'alltrace'.
>

Ok.

I appended 'thread apply all bt' from kgdb to the core.txt, maybe there is 
something interesting in there.

I did notice the following

Thread 17 (Thread 100007):
#0  cpustop_handler () at /usr/src/sys/amd64/amd64/mp_machdep.c:1392
#1  0xffffffff80cbebbd in ipi_nmi_handler () at 
/usr/src/sys/amd64/amd64/mp_machdep.c:1374
#2  0xffffffff80ccc159 in trap (frame=0xffffffff81424890) at 
/usr/src/sys/amd64/amd64/trap.c:211
#3  0xffffffff80cb55af in nmi_calltrap () at 
/usr/src/sys/amd64/amd64/exception.S:501
#4  0xffffffff80d0c029 in vga_txtmouse (scp=0xfffffe0005586600, x=320, y=200, 
on=<value optimized out>) at cpufunc.h:186
Previous frame inner to this frame (corrupt stack?)

Maybe the hang is caused by the removal of the text mouse cursor? (Just guessing 
here.)

Cheers
Michiel