[Nouveau] [bug report] drm/nouveau: move io_reserve_lru handling into the driver v5

[Dan Carpenter]

Hello Christian König,

The patch 141b15e59175: "drm/nouveau: move io_reserve_lru handling
into the driver v5" from Aug 21, 2020, leads to the following static
checker warning:

	drivers/gpu/drm/nouveau/nouveau_ttm.c:148 nouveau_ttm_fault()
	warn: inconsistent returns '*bo->base.resv'.

drivers/gpu/drm/nouveau/nouveau_ttm.c
   126  static vm_fault_t nouveau_ttm_fault(struct vm_fault *vmf)
   127  {
   128          struct vm_area_struct *vma = vmf->vma;
   129          struct ttm_buffer_object *bo = vma->vm_private_data;
   130          pgprot_t prot;
   131          vm_fault_t ret;
   132  
   133          ret = ttm_bo_vm_reserve(bo, vmf);
   134          if (ret)
   135                  return ret;
   136  
   137          nouveau_bo_del_io_reserve_lru(bo);
   138  
   139          prot = vm_get_page_prot(vma->vm_flags);
   140          ret = ttm_bo_vm_fault_reserved(vmf, prot, TTM_BO_VM_NUM_PREFAULT, 1);
   141          if (ret == VM_FAULT_RETRY && !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT))
   142                  return ret;
                        ^^^^^^^^^^
Call dma_resv_unlock() before returning?

   143  
   144          nouveau_bo_add_io_reserve_lru(bo);
   145  
   146          dma_resv_unlock(bo->base.resv);
   147  
   148          return ret;
   149  }

regards,
dan carpenter