Re: [PATCH v2 5/7] dmaengine: idxd: fix memory leak in error handling path of idxd_pci_probe

[Fenghua Yu <fenghuay@nvidia.com>]

Hi, Shuai,

On 2/14/25 21:44, Shuai Xue wrote:
> Memory allocated for idxd is not freed if an error occurs during
> idxd_pci_probe(). To fix it, free the allocated memory in the reverse
> order of allocation before exiting the function in case of an error.
>
> Fixes: bfe1d56091c1 ("dmaengine: idxd: Init and probe for Intel data accelerators")
> Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> ---
>   drivers/dma/idxd/init.c | 10 +++++++++-
>   1 file changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c
> index dc34830fe7c3..ac1cdc1d82bf 100644
> --- a/drivers/dma/idxd/init.c
> +++ b/drivers/dma/idxd/init.c
> @@ -550,6 +550,14 @@ static void idxd_read_caps(struct idxd_device *idxd)
>   		idxd->hw.iaa_cap.bits = ioread64(idxd->reg_base + IDXD_IAACAP_OFFSET);
>   }
>   
> +static void idxd_free(struct idxd_device *idxd)
> +{
> +	put_device(idxd_confdev(idxd));
> +	bitmap_free(idxd->opcap_bmap);
> +	ida_free(&idxd_ida, idxd->id);
> +	kfree(idxd);

opcap_bmap, idxd_ida, idxd are NOT allocated during FLR re-init idxd 
device. In the FLR case, they should not be freed.

> +}
> +
>   static struct idxd_device *idxd_alloc(struct pci_dev *pdev, struct idxd_driver_data *data)
>   {
>   	struct device *dev = &pdev->dev;
> @@ -1219,7 +1227,7 @@ int idxd_pci_probe_alloc(struct idxd_device *idxd, struct pci_dev *pdev,
>    err:
>   	pci_iounmap(pdev, idxd->reg_base);
>    err_iomap:
> -	put_device(idxd_confdev(idxd));
> +	idxd_free(idxd);
>    err_idxd_alloc:
>   	pci_disable_device(pdev);
>   	return rc;


Thanks.


-Fenghua