ib_dma_map_sgtable_attrs() should be mapping the sgls and setting nents but the ib_uses_virt_dma() path falls back to ib_dma_virt_map_sg() which will not set the nents in the sgtable. Check the return value (per the map_sg calling convention) and set sgt->nents appropriately on success. Link: https://lore.kernel.org/all/996fa723-18ef-d35b-c565-c9cb9dc2d5e1@xxxxxxx/T/#u Reported-by: Bart Van Assche <bvanassche@xxxxxxx> Signed-off-by: Logan Gunthorpe <logang@xxxxxxxxxxxx> Tested-by: Bart Van Assche <bvanassche@xxxxxxx> --- include/rdma/ib_verbs.h | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h index 4b50d9a3018a..4ba642fc8a19 100644 --- a/include/rdma/ib_verbs.h +++ b/include/rdma/ib_verbs.h @@ -4097,8 +4097,13 @@ static inline int ib_dma_map_sgtable_attrs(struct ib_device *dev, enum dma_data_direction direction, unsigned long dma_attrs) { + int nents; + if (ib_uses_virt_dma(dev)) { - ib_dma_virt_map_sg(dev, sgt->sgl, sgt->orig_nents); + nents = ib_dma_virt_map_sg(dev, sgt->sgl, sgt->orig_nents); + if (!nents) + return -EIO; + sgt->nents = nents; return 0; } return dma_map_sgtable(dev->dma_device, sgt, direction, dma_attrs); base-commit: 2a152512a155aaf27c3e67834ffafaed9525a7b5 -- 2.30.2
