On Tue, Apr 05, 2022 at 01:16:00PM -0300, Jason Gunthorpe wrote: > diff --git a/drivers/infiniband/hw/usnic/usnic_uiom.c b/drivers/infiniband/hw/usnic/usnic_uiom.c > index 760b254ba42d6b..24d118198ac756 100644 > --- a/drivers/infiniband/hw/usnic/usnic_uiom.c > +++ b/drivers/infiniband/hw/usnic/usnic_uiom.c > @@ -42,6 +42,7 @@ > #include <linux/list.h> > #include <linux/pci.h> > #include <rdma/ib_verbs.h> > +#include <linux/dma-map-ops.h> > > #include "usnic_log.h" > #include "usnic_uiom.h" > @@ -474,6 +475,12 @@ int usnic_uiom_attach_dev_to_pd(struct usnic_uiom_pd *pd, struct device *dev) > struct usnic_uiom_dev *uiom_dev; > int err; > > + if (!dev_is_dma_coherent(dev)) { Which part of the comment at the top of dma-map-ops.h is not clear enough to you?