Re: [PATCH v2] dmaengine: fsl-edma: disable clks on all error paths

From: Vinod Koul
Date: Tue Dec 12 2017 - 23:51:03 EST


On Wed, Dec 06, 2017 at 02:50:23PM +0100, Andreas Platschek wrote:
> Previously enabled clks are only disabled if clk_prepare_enable() fails.
> However, there are other error paths were the previously enabled
> clocks are not disabled.
>
> Found by Linux Driver Verification project (linuxtesting.org).
>
> Signed-off-by: Andreas Platschek <andreas.platschek@xxxxxxxxxxx>
> ---
> drivers/dma/fsl-edma.c | 13 +++++++++++--
> 1 file changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma/fsl-edma.c b/drivers/dma/fsl-edma.c
> index 6775f2c74e25..9940f2f7039f 100644
> --- a/drivers/dma/fsl-edma.c
> +++ b/drivers/dma/fsl-edma.c
> @@ -878,7 +878,7 @@ static int fsl_edma_probe(struct platform_device *pdev)
> struct fsl_edma_chan *fsl_chan;
> struct resource *res;
> int len, chans;
> - int ret, i;
> + int ret, i, j;
>
> ret = of_property_read_u32(np, "dma-channels", &chans);
> if (ret) {
> @@ -904,12 +904,21 @@ static int fsl_edma_probe(struct platform_device *pdev)
>
> res = platform_get_resource(pdev, IORESOURCE_MEM, 1 + i);
> fsl_edma->muxbase[i] = devm_ioremap_resource(&pdev->dev, res);
> - if (IS_ERR(fsl_edma->muxbase[i]))
> + if (IS_ERR(fsl_edma->muxbase[i])) {
> + /* disable only clks which were enabled on error */
> + for (j = i-1; j >= 0; j--)
^^^
space around - pls
> + clk_disable_unprepare(fsl_edma->muxclk[j]);

why not modify fsl_disable_clocks() and invoke that...?

>
> sprintf(clkname, "dmamux%d", i);
> fsl_edma->muxclk[i] = devm_clk_get(&pdev->dev, clkname);
> if (IS_ERR(fsl_edma->muxclk[i])) {
> + /* disable only clks which were enabled on error */
> + for (j = i-1; j >= 0; j--)
> + clk_disable_unprepare(fsl_edma->muxclk[j]);

ditto

--
~Vinod