> From: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxxxxxxxxxxxxx> > Sent: Friday, October 30, 2020 5:50 PM > > On 10/30/2020 8:17 AM, Jason Gunthorpe wrote: > > On Fri, Oct 30, 2020 at 11:38:03AM +0200, Parav Pandit wrote: > >> @@ -1140,7 +1141,10 @@ int rxe_register_device(struct rxe_dev *rxe, > const char *ibdev_name) > >> rxe->ndev->dev_addr); > >> dev->dev.dma_parms = &rxe->dma_parms; > >> dma_set_max_seg_size(&dev->dev, UINT_MAX); > >> - dma_set_coherent_mask(&dev->dev, > dma_get_required_mask(&dev->dev)); > >> + dma_mask = IS_ENABLED(CONFIG_64BIT) ? DMA_BIT_MASK(64) : > DMA_BIT_MASK(32); > >> + err = dma_coerce_mask_and_coherent(&dev->dev, dma_mask); > > > > Since this mask doesn't actually do anything, what is the reason to > > have the 64/32? > Christoph did say 64-bit good enough, but he mentioned that it is not correct on 32-bit platforms. So it is only for theoretical correctness. > Technically there isn't. We are already dependent on 64bit config anyway. > Mike M just brought this up in a side bar conversation actually. For rvt driver, I should drop the check and always set to 64-bit.
