[PATCH] crypto: keembay: Fix dma_unmap_sg() nents value

From: Thomas Fourier
Date: Mon Jun 30 2025 - 04:57:43 EST


The dma_unmap_sg() functions should be called with the same nents as the
dma_map_sg(), not the value the map function returned.

Fixes: 472b04444cd3 ("crypto: keembay - Add Keem Bay OCS HCU driver")
Signed-off-by: Thomas Fourier <fourier.thomas@xxxxxxxxx>
---
drivers/crypto/intel/keembay/keembay-ocs-hcu-core.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/intel/keembay/keembay-ocs-hcu-core.c b/drivers/crypto/intel/keembay/keembay-ocs-hcu-core.c
index 95dc8979918d..8f9e21ced0fe 100644
--- a/drivers/crypto/intel/keembay/keembay-ocs-hcu-core.c
+++ b/drivers/crypto/intel/keembay/keembay-ocs-hcu-core.c
@@ -68,6 +68,7 @@ struct ocs_hcu_ctx {
* @sg_data_total: Total data in the SG list at any time.
* @sg_data_offset: Offset into the data of the current individual SG node.
* @sg_dma_nents: Number of sg entries mapped in dma_list.
+ * @nents: Number of entries in the scatterlist.
*/
struct ocs_hcu_rctx {
struct ocs_hcu_dev *hcu_dev;
@@ -91,6 +92,7 @@ struct ocs_hcu_rctx {
unsigned int sg_data_total;
unsigned int sg_data_offset;
unsigned int sg_dma_nents;
+ unsigned int nents;
};

/**
@@ -199,7 +201,7 @@ static void kmb_ocs_hcu_dma_cleanup(struct ahash_request *req,

/* Unmap req->src (if mapped). */
if (rctx->sg_dma_nents) {
- dma_unmap_sg(dev, req->src, rctx->sg_dma_nents, DMA_TO_DEVICE);
+ dma_unmap_sg(dev, req->src, rctx->nents, DMA_TO_DEVICE);
rctx->sg_dma_nents = 0;
}

@@ -260,6 +262,10 @@ static int kmb_ocs_dma_prepare(struct ahash_request *req)
rc = -ENOMEM;
goto cleanup;
}
+
+ /* Save the value of nents to pass to dma_unmap_sg. */
+ rctx->nents = nents;
+
/*
* The value returned by dma_map_sg() can be < nents; so update
* nents accordingly.
--
2.43.0