[PATCH RESEND] dmaengine: xilinx_dma: Fix uninitialized addr_width when "xlnx,addrwidth" property is missing

[PATCH RESEND] dmaengine: xilinx_dma: Fix uninitialized addr_width when "xlnx,addrwidth" property is missing

[Suraj Gupta]

When device tree lacks optional "xlnx,addrwidth" property, the addr_width
variable remained uninitialized with garbage values, causing incorrect
DMA mask configuration and subsequent probe failure. The fix ensures a
fallback to the default 32-bit address width when this property is missing.

Signed-off-by: Suraj Gupta <suraj.gupta2@amd.com>
Fixes: b72db4005fe4 ("dmaengine: vdma: Add 64 bit addressing support to the driver")
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Reviewed-by: Folker Schwesinger <dev@folker-schwesinger.de>
---
 drivers/dma/xilinx/xilinx_dma.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c
index fabff602065f..89a8254d9cdc 100644
--- a/drivers/dma/xilinx/xilinx_dma.c
+++ b/drivers/dma/xilinx/xilinx_dma.c
@@ -131,6 +131,7 @@
 #define XILINX_MCDMA_MAX_CHANS_PER_DEVICE	0x20
 #define XILINX_DMA_MAX_CHANS_PER_DEVICE		0x2
 #define XILINX_CDMA_MAX_CHANS_PER_DEVICE	0x1
+#define XILINX_DMA_DFAULT_ADDRWIDTH		0x20
 
 #define XILINX_DMA_DMAXR_ALL_IRQ_MASK	\
 		(XILINX_DMA_DMASR_FRM_CNT_IRQ | \
@@ -3159,7 +3160,7 @@ static int xilinx_dma_probe(struct platform_device *pdev)
 	struct device_node *node = pdev->dev.of_node;
 	struct xilinx_dma_device *xdev;
 	struct device_node *child, *np = pdev->dev.of_node;
-	u32 num_frames, addr_width, len_width;
+	u32 num_frames, addr_width = XILINX_DMA_DFAULT_ADDRWIDTH, len_width;
 	int i, err;
 
 	/* Allocate and initialize the DMA engine structure */
@@ -3235,7 +3236,9 @@ static int xilinx_dma_probe(struct platform_device *pdev)
 
 	err = of_property_read_u32(node, "xlnx,addrwidth", &addr_width);
 	if (err < 0)
-		dev_warn(xdev->dev, "missing xlnx,addrwidth property\n");
+		dev_warn(xdev->dev,
+			 "missing xlnx,addrwidth property, using default value %d\n",
+			 XILINX_DMA_DFAULT_ADDRWIDTH);
 
 	if (addr_width > 32)
 		xdev->ext_addr = true;
-- 
2.25.1

RE: [PATCH RESEND] dmaengine: xilinx_dma: Fix uninitialized addr_width when "xlnx,addrwidth" property is missing

[Gupta, Suraj]

[AMD Official Use Only - AMD Internal Distribution Only]

Gentle ping.

Regards,
Suraj

> -----Original Message-----
> From: Suraj Gupta <suraj.gupta2@amd.com>
> Sent: Wednesday, October 22, 2025 12:00 AM
> To: vkoul@kernel.org; Pandey, Radhey Shyam
> <radhey.shyam.pandey@amd.com>; Simek, Michal <michal.simek@amd.com>
> Cc: dmaengine@vger.kernel.org; linux-arm-kernel@lists.infradead.org; linux-
> kernel@vger.kernel.org
> Subject: [PATCH RESEND] dmaengine: xilinx_dma: Fix uninitialized addr_width
> when "xlnx,addrwidth" property is missing
>
> Caution: This message originated from an External Source. Use proper caution
> when opening attachments, clicking links, or responding.
>
>
> When device tree lacks optional "xlnx,addrwidth" property, the addr_width
> variable remained uninitialized with garbage values, causing incorrect DMA
> mask configuration and subsequent probe failure. The fix ensures a fallback to
> the default 32-bit address width when this property is missing.
>
> Signed-off-by: Suraj Gupta <suraj.gupta2@amd.com>
> Fixes: b72db4005fe4 ("dmaengine: vdma: Add 64 bit addressing support to the
> driver")
> Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
> Reviewed-by: Folker Schwesinger <dev@folker-schwesinger.de>
> ---
>  drivers/dma/xilinx/xilinx_dma.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c
> index fabff602065f..89a8254d9cdc 100644
> --- a/drivers/dma/xilinx/xilinx_dma.c
> +++ b/drivers/dma/xilinx/xilinx_dma.c
> @@ -131,6 +131,7 @@
>  #define XILINX_MCDMA_MAX_CHANS_PER_DEVICE      0x20
>  #define XILINX_DMA_MAX_CHANS_PER_DEVICE                0x2
>  #define XILINX_CDMA_MAX_CHANS_PER_DEVICE       0x1
> +#define XILINX_DMA_DFAULT_ADDRWIDTH            0x20
>
>  #define XILINX_DMA_DMAXR_ALL_IRQ_MASK  \
>                 (XILINX_DMA_DMASR_FRM_CNT_IRQ | \ @@ -3159,7 +3160,7 @@
> static int xilinx_dma_probe(struct platform_device *pdev)
>         struct device_node *node = pdev->dev.of_node;
>         struct xilinx_dma_device *xdev;
>         struct device_node *child, *np = pdev->dev.of_node;
> -       u32 num_frames, addr_width, len_width;
> +       u32 num_frames, addr_width = XILINX_DMA_DFAULT_ADDRWIDTH,
> + len_width;
>         int i, err;
>
>         /* Allocate and initialize the DMA engine structure */ @@ -3235,7
> +3236,9 @@ static int xilinx_dma_probe(struct platform_device *pdev)
>
>         err = of_property_read_u32(node, "xlnx,addrwidth", &addr_width);
>         if (err < 0)
> -               dev_warn(xdev->dev, "missing xlnx,addrwidth property\n");
> +               dev_warn(xdev->dev,
> +                        "missing xlnx,addrwidth property, using default value %d\n",
> +                        XILINX_DMA_DFAULT_ADDRWIDTH);
>
>         if (addr_width > 32)
>                 xdev->ext_addr = true;
> --
> 2.25.1
>

Re: [PATCH RESEND] dmaengine: xilinx_dma: Fix uninitialized addr_width when "xlnx,addrwidth" property is missing

[Vinod Koul]

On Wed, 22 Oct 2025 00:00:06 +0530, Suraj Gupta wrote:
> When device tree lacks optional "xlnx,addrwidth" property, the addr_width
> variable remained uninitialized with garbage values, causing incorrect
> DMA mask configuration and subsequent probe failure. The fix ensures a
> fallback to the default 32-bit address width when this property is missing.
> 
> 

Applied, thanks!

[1/1] dmaengine: xilinx_dma: Fix uninitialized addr_width when "xlnx,addrwidth" property is missing
      commit: c0732fe78728718c853ef8e7af5bbb05262acbd1

Best regards,
-- 
~Vinod