Re: [PATCH] drm/xe: Fix NPD when saving default context

[Matthew Brost <matthew.brost@intel.com>]

On Wed, May 28, 2025 at 10:55:03PM -0600, Upadhyay, Tejas wrote:
> 
> 
> > -----Original Message-----
> > From: Intel-xe <intel-xe-bounces@lists.freedesktop.org> On Behalf Of Lucas
> > De Marchi
> > Sent: 29 May 2025 03:12
> > To: intel-xe@lists.freedesktop.org
> > Cc: Brost, Matthew <matthew.brost@intel.com>; dri-
> > devel@lists.freedesktop.org; De Marchi, Lucas <lucas.demarchi@intel.com>;
> > Christian König <christian.koenig@amd.com>; Pierre-Eric Pelloux-Prayer
> > <pierre-eric.pelloux-prayer@amd.com>; Philipp Stanner
> > <phasta@kernel.org>
> > Subject: [PATCH] drm/xe: Fix NPD when saving default context
> > 
> > xef is only valid if it's a job from userspace.  For in-kernel jobs it causes a NPD
> > like below:
> > 
> >         <4> [] RIP: 0010:xe_sched_job_create+0xbd/0x390 [xe]
> > 	...
> >         <4> [] Call Trace:
> >         <4> []  <TASK>
> >         <4> []  __xe_bb_create_job+0xa2/0x240 [xe]
> >         <4> []  ? find_held_lock+0x31/0x90
> >         <4> []  ? xa_find_after+0x12c/0x250
> >         <4> []  xe_bb_create_job+0x6e/0x380 [xe]
> >         <4> []  ? xa_find_after+0x136/0x250
> >         <4> []  ? __drm_dev_dbg+0x7d/0xb0
> >         <4> []  xe_gt_record_default_lrcs+0x542/0xb00 [xe]
> > 
> > Since drm_file starts with 1 for the unique id, just use 0 for the in-kernel jobs.
> > 
> > Fixes: 2956554823ce ("drm/sched: Store the drm client_id in
> > drm_sched_fence")
> > Cc: Christian König <christian.koenig@amd.com>
> > Cc: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
> > Cc: Philipp Stanner <phasta@kernel.org>
> > Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
> > ---
> >  drivers/gpu/drm/xe/xe_sched_job.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/xe/xe_sched_job.c
> > b/drivers/gpu/drm/xe/xe_sched_job.c
> > index 5921293b25db3..d21bf8f269640 100644
> > --- a/drivers/gpu/drm/xe/xe_sched_job.c
> > +++ b/drivers/gpu/drm/xe/xe_sched_job.c
> > @@ -114,7 +114,7 @@ struct xe_sched_job *xe_sched_job_create(struct
> > xe_exec_queue *q,
> >  	xe_exec_queue_get(job->q);
> > 
> >  	err = drm_sched_job_init(&job->drm, q->entity, 1, NULL,
> > -				 q->xef->drm->client_id);
> > +				 q->xef ? q->xef->drm->client_id : 0);
> 
> drm_sched_job_init() has only 4 args!
> 

This patch added a 5th:

2956554823ce drm/sched: Store the drm client_id in drm_sched_fence

Matt

> Tejas
> 
> >  	if (err)
> >  		goto err_free;
> > 
> > 
> > 
>