Re: [PATCH] crypto: sun8i-ce: Fix `dma_unmap_sg()` nents value

From: Ovidiu Panait
Date: Mon Jun 23 2025 - 06:45:57 EST


Hi Thomas,

On 6/23/25 12:10 PM, Thomas Fourier wrote:
> The `dma_unmap_sg()` functions should be called with the same nents as the
> `dma_map_sg()`, not the value the map function returned.
>

This should already be fixed by:
https://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git/commit/?id=b6cd3cfb5afe49952f8f6be947aeeca9ba0faebb

The sg nents are saved to request context during prepare() and then used
in unprepare().

Thanks,
Ovidiu

> Fixes: 0605fa0f7826 ("crypto: sun8i-ce - split into prepare/run/unprepare")
> Signed-off-by: Thomas Fourier <fourier.thomas@xxxxxxxxx>
> ---
> drivers/crypto/allwinner/sun8i-ce/sun8i-ce-cipher.c | 12 ++++++------
> 1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-cipher.c b/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-cipher.c
> index f9cf00d690e2..ce9d071f5693 100644
> --- a/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-cipher.c
> +++ b/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-cipher.c
> @@ -326,8 +326,8 @@ static void sun8i_ce_cipher_unprepare(struct crypto_engine *engine,
> struct sun8i_ce_flow *chan;
> struct ce_task *cet;
> unsigned int ivsize, offset;
> - int nr_sgs = rctx->nr_sgs;
> - int nr_sgd = rctx->nr_sgd;
> + int ns = sg_nents_for_len(areq->src, areq->cryptlen);
> + int nd = sg_nents_for_len(areq->dst, areq->cryptlen);
> int flow;
>
> flow = rctx->flow;
> @@ -336,11 +336,11 @@ static void sun8i_ce_cipher_unprepare(struct crypto_engine *engine,
> ivsize = crypto_skcipher_ivsize(tfm);
>
> if (areq->src == areq->dst) {
> - dma_unmap_sg(ce->dev, areq->src, nr_sgs, DMA_BIDIRECTIONAL);
> + dma_unmap_sg(ce->dev, areq->src, ns, DMA_BIDIRECTIONAL);
> } else {
> - if (nr_sgs > 0)
> - dma_unmap_sg(ce->dev, areq->src, nr_sgs, DMA_TO_DEVICE);
> - dma_unmap_sg(ce->dev, areq->dst, nr_sgd, DMA_FROM_DEVICE);
> + if (rctx->nr_sgs > 0)
> + dma_unmap_sg(ce->dev, areq->src, ns, DMA_TO_DEVICE);
> + dma_unmap_sg(ce->dev, areq->dst, nd, DMA_FROM_DEVICE);
> }
>
> if (areq->iv && ivsize > 0) {