[Nouveau] [BUG][NOUVEAU] G70 broken since 5.10-rc1

[Mark Hounschell]

On 11/26/20 7:41 AM, Christian König wrote:
> Hi Mark,
> 
> Am 26.11.20 um 13:26 schrieb Mark Hounschell:
>> On 11/26/20 7:05 AM, Christian König wrote:
>>> Hi Mark,
>>>
>>> Am 26.11.20 um 10:59 schrieb Mark Hounschell:
>>>> On 11/26/20 3:35 AM, Christian König wrote:
>>>>>> I'm running an older "NVIDIA Corporation G70 [GeForce 7800 GT] (rev 
>>>>>> a1)" card in a newer BIOSTAR B550GTA MB. Kernel 5.10-rcx does not 
>>>>>> work. I get no virtual consoles or X screen.
>>>
>>> thanks for the dmesg.
>>>
>>> Problem is I don't have the slightest idea what's going wrong here :)
>>>
>>> The code should be functional identical, it was just moved from TTM to 
>>> nouveau, so we are missing some detail in the handling.
>>>
>>> Can you run the following test for me: First you need to disable loading 
>>> of the nouveau kernel module by adding modprobe.blacklist=nouveau to the 
>>> kernel command line.
>>>
>>> Then log into the system over the network and run the following commands:
>>>
>>> sudo modprobe ttm
>>> sudo bash -c "echo 'ttm_bo_kmap' > 
>>> /sys/kernel/debug/tracing/set_graph_function"
>>> sudo bash -c "echo function_graph > 
>>> /sys/kernel/debug/tracing/current_tracer"
>>> sudo modprobe nouveau
>>> sudo bash -c "cat /sys/kernel/debug/tracing/trace" > trace.log
>>>
>>> Please then send me the resulting trace.log file so that I can 
>>> investigate why mapping the framebuffer fails during driver load.
>>>
>>> Thanks in advance,
>>> Christian.
>>
>> I hope this is what you need. I do normally turn off a lot of debug 
>> features. Let me know if I need to change the kernel config.
> 
> It was not what I had expected but it pointed me in the right direction. I 
> think I've found the problem, it's just an uninitialized return value for 
> your hardware generation.
> 
> Please try the attached patch and let me know if it fixes the problem.
> 
> Thanks in advance,
> Christian.

Yep, that fixed it.  -rc6?

Thanks
Mark