Re: [EXTERNAL] Re: [PATCH 05/12] net: mana: Set the DMA device max page size
From: Jason Gunthorpe <jgg@ziepe.ca>
Date: 2022-05-18 16:05:35
Also in:
linux-hyperv, linux-rdma, lkml
From: Jason Gunthorpe <jgg@ziepe.ca>
Date: 2022-05-18 16:05:35
Also in:
linux-hyperv, linux-rdma, lkml
On Wed, May 18, 2022 at 05:59:00AM +0000, Ajay Sharma wrote:
Thanks Long. Hello Jason, I am the author of the patch. To your comment below : " As I've already said, you are supposed to set the value that limits to ib_sge and *NOT* the value that is related to ib_umem_find_best_pgsz. It is usually 2G because the ib_sge's typically work on a 32 bit length." The ib_sge is limited by the __sg_alloc_table_from_pages() which uses ib_dma_max_seg_size() which is what is set by the eth driver using dma_set_max_seg_size() . Currently our hw does not support PTEs larger than 2M.
*sigh* again it has nothing to do with *PTEs* in the HW. Jason