[PATCH net,v2] net: wan/fsl_ucc_hdlc: Fix dma_free_coherent() in uhdlc_memclean()

Thomas Fourier fourier.thomas at gmail.com
Fri Feb 6 19:53:33 AEDT 2026


The priv->rx_buffer and priv->tx_buffer are alloc'd together as
contiguous buffers in uhdlc_init() but freed as two buffers in
uhdlc_memclean().

Change the cleanup to only call dma_free_coherent() once on the whole
buffer.

Reviewed-by: Christophe Leroy (CS GROUP) <chleroy at kernel.org>
Fixes: c19b6d246a35 ("drivers/net: support hdlc function for QE-UCC")
Cc: <stable at vger.kernel.org>
Signed-off-by: Thomas Fourier <fourier.thomas at gmail.com>
---
v1->v2:
  - Cleanup priv->tx_buffer and priv->dma_tx_addr
  - Fix buffer name in commit message

 drivers/net/wan/fsl_ucc_hdlc.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/net/wan/fsl_ucc_hdlc.c b/drivers/net/wan/fsl_ucc_hdlc.c
index f999798a5612..dff84731343c 100644
--- a/drivers/net/wan/fsl_ucc_hdlc.c
+++ b/drivers/net/wan/fsl_ucc_hdlc.c
@@ -790,18 +790,14 @@ static void uhdlc_memclean(struct ucc_hdlc_private *priv)
 
 	if (priv->rx_buffer) {
 		dma_free_coherent(priv->dev,
-				  RX_BD_RING_LEN * MAX_RX_BUF_LENGTH,
+				  (RX_BD_RING_LEN + TX_BD_RING_LEN) * MAX_RX_BUF_LENGTH,
 				  priv->rx_buffer, priv->dma_rx_addr);
 		priv->rx_buffer = NULL;
 		priv->dma_rx_addr = 0;
-	}
 
-	if (priv->tx_buffer) {
-		dma_free_coherent(priv->dev,
-				  TX_BD_RING_LEN * MAX_RX_BUF_LENGTH,
-				  priv->tx_buffer, priv->dma_tx_addr);
 		priv->tx_buffer = NULL;
 		priv->dma_tx_addr = 0;
+
 	}
 }
 
-- 
2.43.0



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