[RFC v1 1/1] drm/xe: Allow fault injection in vm create and vm bind IOCTLs

[Francois Dugast]

On Fri, Nov 08, 2024 at 03:10:13PM -0500, Rodrigo Vivi wrote:
> On Fri, Nov 08, 2024 at 05:11:56PM +0100, Francois Dugast wrote:
> > Use fault injection infrastructure to allow specific functions to
> > be configured over debugfs for failing during the execution of
> > xe_vm_create_ioctl() and xe_vm_bind_ioctl(). This allows more
> > thorough testing from user space by going through code paths for
> > error handling and unwinding which cannot be reached by simply
> > injecting errors in IOCTL arguments. This can help increase code
> > robustness.
> > 
> > Signed-off-by: Francois Dugast <francois.dugast at intel.com>
> 
> Reviewed-by: Rodrigo Vivi <rodrigo.vivi at intel.com>

Thanks! May I retain the RB after applying the diff suggested here [1] which
adds xe_pt_update_ops_{prepare,run} to the ALLOW_ERROR_INJECTION functions?

[1] https://lore.kernel.org/intel-xe/20241108161307.1203967-1-francois.dugast@intel.com/T/#m69d0b496c82f739e2093710fa8b8d7ff9f4ae712

Francois

> 
> > ---
> >  drivers/gpu/drm/xe/xe_exec_queue.c | 1 +
> >  drivers/gpu/drm/xe/xe_pt.c         | 1 +
> >  drivers/gpu/drm/xe/xe_vm.c         | 4 ++++
> >  3 files changed, 6 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/xe/xe_exec_queue.c b/drivers/gpu/drm/xe/xe_exec_queue.c
> > index fd0f3b3c9101..b999db5f5c19 100644
> > --- a/drivers/gpu/drm/xe/xe_exec_queue.c
> > +++ b/drivers/gpu/drm/xe/xe_exec_queue.c
> > @@ -240,6 +240,7 @@ struct xe_exec_queue *xe_exec_queue_create_bind(struct xe_device *xe,
> >  
> >  	return q;
> >  }
> > +ALLOW_ERROR_INJECTION(xe_exec_queue_create_bind, ERRNO);
> >  
> >  void xe_exec_queue_destroy(struct kref *ref)
> >  {
> > diff --git a/drivers/gpu/drm/xe/xe_pt.c b/drivers/gpu/drm/xe/xe_pt.c
> > index f27f579f4d85..e111698abbd9 100644
> > --- a/drivers/gpu/drm/xe/xe_pt.c
> > +++ b/drivers/gpu/drm/xe/xe_pt.c
> > @@ -136,6 +136,7 @@ struct xe_pt *xe_pt_create(struct xe_vm *vm, struct xe_tile *tile,
> >  	xe_pt_free(pt);
> >  	return ERR_PTR(err);
> >  }
> > +ALLOW_ERROR_INJECTION(xe_pt_create, ERRNO);
> >  
> >  /**
> >   * xe_pt_populate_empty() - Populate a page-table bo with scratch- or zero
> > diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
> > index 624133fae5f5..2e67648ed512 100644
> > --- a/drivers/gpu/drm/xe/xe_vm.c
> > +++ b/drivers/gpu/drm/xe/xe_vm.c
> > @@ -740,6 +740,7 @@ static int xe_vma_ops_alloc(struct xe_vma_ops *vops, bool array_of_binds)
> >  
> >  	return 0;
> >  }
> > +ALLOW_ERROR_INJECTION(xe_vma_ops_alloc, ERRNO);
> >  
> >  static void xe_vma_ops_fini(struct xe_vma_ops *vops)
> >  {
> > @@ -1352,6 +1353,7 @@ static int xe_vm_create_scratch(struct xe_device *xe, struct xe_tile *tile,
> >  
> >  	return 0;
> >  }
> > +ALLOW_ERROR_INJECTION(xe_vm_create_scratch, ERRNO);
> >  
> >  static void xe_vm_free_scratch(struct xe_vm *vm)
> >  {
> > @@ -1978,6 +1980,7 @@ vm_bind_ioctl_ops_create(struct xe_vm *vm, struct xe_bo *bo,
> >  
> >  	return ops;
> >  }
> > +ALLOW_ERROR_INJECTION(vm_bind_ioctl_ops_create, ERRNO);
> >  
> >  static struct xe_vma *new_vma(struct xe_vm *vm, struct drm_gpuva_op_map *op,
> >  			      u16 pat_index, unsigned int flags)
> > @@ -2697,6 +2700,7 @@ static int vm_bind_ioctl_ops_execute(struct xe_vm *vm,
> >  	drm_exec_fini(&exec);
> >  	return err;
> >  }
> > +ALLOW_ERROR_INJECTION(vm_bind_ioctl_ops_execute, ERRNO);
> >  
> >  #define SUPPORTED_FLAGS_STUB  \
> >  	(DRM_XE_VM_BIND_FLAG_READONLY | \
> > -- 
> > 2.43.0
> >