After Vega 56/64 GPU hang I unable reboot system

[StDenis, Tom]

On 2018-12-20 11:07 a.m., Mikhail Gavrilov wrote:
> On Thu, 20 Dec 2018 at 19:19, StDenis, Tom <Tom.StDenis at amd.com> wrote:
>>
>> Ya I was right.  With a plain build I can access the files just fine.
>>
>>
>>
>> I did manage to get into a weird shell where I couldn't cat
>> amdgpu_gca_config from bash though after a reboot (had updates pending)
>> it works fine.
>>
>> If you can't cat those files then neither can umr.
>>
>> So NOTABUG :-)
>>
> 
> I am very happy for you. But what about me?
> I don't have idea how make this files available on my system.
> And of course I tried reboot and try again cat amdgpu_gca_config
> several times but all times without success.

Sorry I didn't mean to be dismissive.  It's just not a bug in umr though.

On Fedora I can access those files as root just fine:

tom at fx8:~$ sudo bash
[sudo] password for tom:
root at fx8:/home/tom# cd /sys/kernel/debug/dri/0
root at fx8:/sys/kernel/debug/dri/0# xxd -e amdgpu_gca_config
00000000: 00000003 00000001 00000004 0000000b  ................
00000010: 00000001 00000002 00000004 00000100  ................
00000020: 00000020 00000008 00000020 00000100   ....... .......
00000030: 00000030 000004c0 00000000 00000003  0...............
00000040: 00000000 00000000 00000000 00000000  ................
00000050: 00000000 00000000 24000042 00000002  ........B..$....
00000060: 00000001 00004100 017f9fcf 0000008e  .....A..........
00000070: 00000001 000015dd 000000c6 0000d000  ................
00000080: 00001458                             X...
root at fx8:/sys/kernel/debug/dri/0#

There must be some sort of ACL or something going on here.

Tom

> 
> Also I note that not all files not permitted for read from
> /sys/kernel/debug/dri/0/*
> I was able to dump contents of some files in debugfs.txt (see attachments)
> List of available for readind files:
> amdgpu_evict_gtt
> amdgpu_evict_vram
> amdgpu_fence_info
> amdgpu_firmware_info
> amdgpu_gds_mm
> amdgpu_gem_info
> amdgpu_gpu_recover
> amdgpu_gtt_mm
> amdgpu_gws_mm
> amdgpu_oa_mm
> amdgpu_pm_info
> amdgpu_sa_info
> amdgpu_test_ib
> amdgpu_vbios
> amdgpu_vram_mm
> clients
> framebuffer
> gem_names
> internal_clients
> name
> state
> ttm_page_pool
> 
> May some kernel options restrict access for files in debugfs (for
> example to amdgpu_gca_config)?
> If yes on which options should I pay attention?
> I have no more ideas. I tried everything.
> 
> 
> 
> 
> --
> Best Regards,
> Mike Gavrilov.
>