[PATCH 1/1] drm/xe: Fix NPD in ggtt_node_remove()

[Ghimiray, Himal Prasad]

On 28-08-2024 14:20, Upadhyay, Tejas wrote:
> 
> 
>> -----Original Message-----
>> From: Upadhyay, Tejas
>> Sent: Wednesday, August 28, 2024 2:13 PM
>> To: Ghimiray, Himal Prasad <himal.prasad.ghimiray at intel.com>; intel-
>> xe at lists.freedesktop.org
>> Cc: Vivi, Rodrigo <rodrigo.vivi at intel.com>; De Marchi, Lucas
>> <lucas.demarchi at intel.com>
>> Subject: RE: [PATCH 1/1] drm/xe: Fix NPD in ggtt_node_remove()
>>
>>
>>
>>> -----Original Message-----
>>> From: Ghimiray, Himal Prasad <himal.prasad.ghimiray at intel.com>
>>> Sent: Wednesday, August 28, 2024 2:25 PM
>>> To: intel-xe at lists.freedesktop.org
>>> Cc: Ghimiray, Himal Prasad <himal.prasad.ghimiray at intel.com>; Vivi,
>>> Rodrigo <rodrigo.vivi at intel.com>; De Marchi, Lucas
>>> <lucas.demarchi at intel.com>; Upadhyay, Tejas <tejas.upadhyay at intel.com>
>>> Subject: [PATCH 1/1] drm/xe: Fix NPD in ggtt_node_remove()
>>>
>>> Make sure that ggtt_node_remove() is invoked only if both node and
>>> ggtt are not null. Move the null checks to the caller function
>> xe_ggtt_node_remove().
>>>
>>> Fixes: 919bb54e989c ("drm/xe: Fix missing runtime outer protection for
>>> ggtt_remove_node")
>>> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
>>> Cc: Lucas De Marchi <lucas.demarchi at intel.com>
>>> Cc: Tejas Upadhyay <tejas.upadhyay at intel.com>
>>> Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray at intel.com>
>>> ---
>>>   drivers/gpu/drm/xe/xe_ggtt.c | 6 +++---
>>>   1 file changed, 3 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/xe/xe_ggtt.c
>>> b/drivers/gpu/drm/xe/xe_ggtt.c index 86fc6afa43bd..2fa8a22ebbf9 100644
>>> --- a/drivers/gpu/drm/xe/xe_ggtt.c
>>> +++ b/drivers/gpu/drm/xe/xe_ggtt.c
>>> @@ -286,9 +286,6 @@ static void ggtt_node_remove(struct xe_ggtt_node
>>> *node)
>>>   	bool bound;
>>>   	int idx;
>>>
>>> -	if (!node || !node->ggtt)
>>> -		return;
>>> -
>>>   	bound = drm_dev_enter(&xe->drm, &idx);
>>>
>>>   	mutex_lock(&ggtt->lock);
>>> @@ -328,6 +325,9 @@ static void ggtt_node_remove_work_func(struct
>>> work_struct *work)
>>>    */
>>>   void xe_ggtt_node_remove(struct xe_ggtt_node *node, bool invalidate)
>>> {
>>> +	if (!node || !node->ggtt)
>>> +		return;
>>> +
>>
>> I think better to declare and assign after NULL check. Something like below,
>> struct xe_ggtt *ggtt; struct xe_device *xe; ....
>> ....
>> if (!node || !node->ggtt)
>>           return;
>> ggtt = node->ggtt;
>> xe = tile_to_xe(ggtt->tile);

Sure.

>>
> 
> With that,
> Reviewed-by: Tejas Upadhyay <tejas.upadhyay at intel.com>
> 
>> Thanks,
>> Tejas
>>>   	struct xe_ggtt *ggtt = node->ggtt;
>>>   	struct xe_device *xe = tile_to_xe(ggtt->tile);
>>>
>>> --
>>> 2.34.1
>