If ib_umem_find_best_pgsz() returns > PAGE_SIZE then the equation here is not correct. 'start' should be 'virt'. Change it to use the core code for page_num and the canonical calculation of page_shift. Fixes: 40ddb3f02083 ("RDMA/efa: Use API to get contiguous memory blocks aligned to device supported page size") Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx> --- drivers/infiniband/hw/efa/efa_verbs.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/infiniband/hw/efa/efa_verbs.c b/drivers/infiniband/hw/efa/efa_verbs.c index d85c63a5021a70..72da0faa7ebf97 100644 --- a/drivers/infiniband/hw/efa/efa_verbs.c +++ b/drivers/infiniband/hw/efa/efa_verbs.c @@ -4,6 +4,7 @@ */ #include <linux/vmalloc.h> +#include <linux/log2.h> #include <rdma/ib_addr.h> #include <rdma/ib_umem.h> @@ -1538,9 +1539,8 @@ struct ib_mr *efa_reg_mr(struct ib_pd *ibpd, u64 start, u64 length, goto err_unmap; } - params.page_shift = __ffs(pg_sz); - params.page_num = DIV_ROUND_UP(length + (start & (pg_sz - 1)), - pg_sz); + params.page_shift = order_base_2(pg_sz); + params.page_num = ib_umem_num_dma_blocks(mr->umem, pg_sz); ibdev_dbg(&dev->ibdev, "start %#llx length %#llx params.page_shift %u params.page_num %u\n", -- 2.28.0