Re: [Intel-gfx] [PATCH] drm/i915/ttm: Abort suspend on i915_ttm_backup failure

["Das, Nirmoy" <nirmoy.das@linux.intel.com>]

On 9/1/2022 5:57 PM, Andrzej Hajda wrote:
> On 31.08.2022 18:18, Nirmoy Das wrote:
>> On system suspend when system memory is low then i915_gem_obj_copy_ttm()
>> could fail trying to backup a lmem obj. GEM_WARN_ON() is not enough,
>> suspend shouldn't continue if i915_ttm_backup() throws an error.
>>
>> References: https://gitlab.freedesktop.org/drm/intel/-/issues/6529
>> Reviewed-by: Matthew Auld <matthew.auld@intel.com>
>> Suggested-by: Chris P Wilson <chris.p.wilson@intel.com>
>> Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
>> ---
>>   drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c | 7 ++++++-
>>   1 file changed, 6 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c 
>> b/drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c
>> index 9aad84059d56..6f5d5c0909b4 100644
>> --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c
>> +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c
>> @@ -79,7 +79,12 @@ static int i915_ttm_backup(struct 
>> i915_gem_apply_to_region *apply,
>>           goto out_no_populate;
>>         err = i915_gem_obj_copy_ttm(backup, obj, pm_apply->allow_gpu, 
>> false);
>> -    GEM_WARN_ON(err);
>> +    if (err) {
>> +        drm_err(&i915->drm,
>> +            "Unable to copy from device to system memory, err:%d\n",
>> +            err);
>
> I wonder if %pe wouldn't be better here, up to you.


More readable err should be useful, resend with %pe.

>
> Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>


Thanks,

Nirmoy

>
> Regards
> Andrzej
>
>
>> +        goto out_no_populate;
>> +    }
>>       ttm_bo_wait_ctx(backup_bo, &ctx);
>>         obj->ttm.backup = backup;
>