On Thu, Jun 4, 2026 at 5:43 AM Leon Romanovsky leon@kernel.org wrote:
On Mon, Jun 01, 2026 at 08:00:12PM +0000, David Hu wrote:
@@ -36,7 +36,7 @@ static unsigned int calc_sg_nents(struct dma_iova_state *state, struct phys_vec *phys_vec, size_t nr_ranges, size_t size) {
unsigned int nents = 0;
size_t nents = 0; size_t i; if (!state || !dma_use_iova(state)) {@@ -51,6 +51,9 @@ static unsigned int calc_sg_nents(struct dma_iova_state *state, nents = DIV_ROUND_UP(size, UINT_MAX); }
if (nents > UINT_MAX)I would suggest to use check_add_overflow() while calculating nents instead of this check.
Hi Leon,
Thank you for the review. Using `check_add_overflow()` is a great suggestion and definitely cleaner for the accumulation loop. I'll update this for v6.
@@ -133,6 +137,11 @@ struct sg_table *dma_buf_phys_vec_to_sgt(struct dma_buf_attachment *attach, }
nents = calc_sg_nents(dma->state, phys_vec, nr_ranges, size);
if (!nents) {ret = -EINVAL;goto err_free_state;}Technically, this hunk is not necessary, since sg_alloc_table() will return -EINVAL when nents == 0. At least, that is the behavior I relied on.
I originally added this explicit check in v5 to address Jason's feedback, and to make the failure explicit rather than relying on `sg_alloc_table()` failing silently on `nents=0`.
Jason, do you have a strong preference here? I am happy to drop the hunk and rely on `sg_alloc_table()` returning `-EINVAL` if you are both comfortable with that.
Thanks, David