Am Mittwoch, den 06.06.2018, 10:48 -0700 schrieb Eric Anholt: > Between creation and queueing of a job, you need to prevent any other > job from being created and queued.  Otherwise the scheduler's fences > may be signaled out of seqno order. > > v2: move mutex unlock to the error label. > > > Signed-off-by: Eric Anholt <eric at anholt.net> > Fixes: 57692c94dcbe ("drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+") Reviewed-by: Lucas Stach <l.stach at pengutronix.de> > --- >  drivers/gpu/drm/v3d/v3d_drv.h | 5 +++++ >  drivers/gpu/drm/v3d/v3d_gem.c | 4 ++++ >  2 files changed, 9 insertions(+) > > diff --git a/drivers/gpu/drm/v3d/v3d_drv.h b/drivers/gpu/drm/v3d/v3d_drv.h > index a043ac3aae98..26005abd9c5d 100644 > --- a/drivers/gpu/drm/v3d/v3d_drv.h > +++ b/drivers/gpu/drm/v3d/v3d_drv.h > @@ -85,6 +85,11 @@ struct v3d_dev { > >   */ > >  struct mutex reset_lock; >  > > + /* Lock taken when creating and pushing the GPU scheduler > > +  * jobs, to keep the sched-fence seqnos in order. > > +  */ > > + struct mutex sched_lock; > + > >  struct { > >  u32 num_allocated; > >  u32 pages_allocated; > diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c > index b513f9189caf..269fe16379c0 100644 > --- a/drivers/gpu/drm/v3d/v3d_gem.c > +++ b/drivers/gpu/drm/v3d/v3d_gem.c > @@ -550,6 +550,7 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data, > >  if (ret) > >  goto fail; >  > > + mutex_lock(&v3d->sched_lock); > >  if (exec->bin.start != exec->bin.end) { > >  ret = drm_sched_job_init(&exec->bin.base, > >   &v3d->queue[V3D_BIN].sched, > @@ -576,6 +577,7 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data, > >  kref_get(&exec->refcount); /* put by scheduler job completion */ > >  drm_sched_entity_push_job(&exec->render.base, > >    &v3d_priv->sched_entity[V3D_RENDER]); > > + mutex_unlock(&v3d->sched_lock); >  > >  v3d_attach_object_fences(exec); >  > @@ -594,6 +596,7 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data, > >  return 0; >  >  fail_unreserve: > > + mutex_unlock(&v3d->sched_lock); > >  v3d_unlock_bo_reservations(dev, exec, &acquire_ctx); >  fail: > >  v3d_exec_put(exec); > @@ -615,6 +618,7 @@ v3d_gem_init(struct drm_device *dev) > >  spin_lock_init(&v3d->job_lock); > >  mutex_init(&v3d->bo_lock); > >  mutex_init(&v3d->reset_lock); > > + mutex_init(&v3d->sched_lock); >  > >  /* Note: We don't allocate address 0.  Various bits of HW > >   * treat 0 as special, such as the occlusion query counters