Re: atomic changes break drm-next-kmod?

From: Pete Wright <pete_at_nomadlogic.org>
Date: Thu, 5 Jul 2018 10:48:16 -0700
On 07/05/2018 10:10, John Baldwin wrote:
> On 7/3/18 5:10 PM, Pete Wright wrote:
>>
>> On 07/03/2018 15:56, John Baldwin wrote:
>>> On 7/3/18 3:34 PM, Pete Wright wrote:
>>>> On 07/03/2018 15:29, John Baldwin wrote:
>>>>> That seems like kgdb is looking at the wrong CPU.  Can you use
>>>>> 'info threads' and look for threads not stopped in 'sched_switch'
>>>>> and get their backtraces?  You could also just do 'thread apply
>>>>> all bt' and put that file at a URL if that is easiest.
>>>>>
>>>> sure thing John - here's a gist of "thread apply all bt"
>>>>
>>>> https://gist.github.com/gem-pete/d8d7ab220dc8781f0827f965f09d43ed
>>> That doesn't look right at all.  Are you sure the kernel matches the
>>> vmcore?  Also, which kgdb version are you using?
>>>
>> yea i agree that doesn't look right at all.  here is my setup:
>>
>> $ which kgdb
>> /usr/bin/kgdb
>> $ kgdb
>> GNU gdb 6.1.1 [FreeBSD]
>> $ ls -lh /var/crash/vmcore.1
>> -rw-------  1 root  wheel   1.6G Jul  3 15:03 /var/crash/vmcore.1
>> $ ls -l /usr/lib/debug/boot/kernel/kernel.debug
>> -r-xr-xr-x  1 root  wheel  87840496 Jul  3 13:54
>> /usr/lib/debug/boot/kernel/kernel.debug
>>
>> and i invoke kgdb like so:
>> $ sudo kgdb /usr/lib/debug/boot/kernel/kernel.debug /var/crash/vmcore.1
>>
>> here's a gist of my full gdb session:
>> http://termbin.com/krsn
>>
>> dunno - maybe i have a bad core dump?  regardless, more than happy to
>> help so let me know if i should try anything else or patches etc..
> Can you try installing gdb from ports and using /usr/local/bin/kgdb?
>

that seems to have done the trick, at least the output looks more 
encouraging.

  --- trap 0, rip = 0, rsp = 0, rbp = 0 ---
KDB: enter: panic

__curthread () at ./machine/pcpu.h:231
231        __asm("movq %%gs:%1,%0" : "=r" (td)


here's my full kgdb session:
http://termbin.com/qa4f

i don't see any threads not in "sched_switch" though :(

-pete


-- 
Pete Wright
pete_at_nomadlogic.org
_at_nomadlogicLA
Received on Thu Jul 05 2018 - 15:48:23 UTC

This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:41:16 UTC