> On 8 Mar 2022, at 19:46, Vikram Garhwal <[email protected]> wrote:
>
> Protect iommu_add_dt_device() with dtdevs_lock to prevent concurrent access
> add.
>
> Signed-off-by: Vikram Garhwal <[email protected]>
Reviewed-by: Luca Fancellu <[email protected]>
> ---
> xen/drivers/passthrough/device_tree.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/xen/drivers/passthrough/device_tree.c
> b/xen/drivers/passthrough/device_tree.c
> index b3b04f8e03..776809a8f2 100644
> --- a/xen/drivers/passthrough/device_tree.c
> +++ b/xen/drivers/passthrough/device_tree.c
> @@ -145,6 +145,8 @@ int iommu_add_dt_device(struct dt_device_node *np)
> if ( dev_iommu_fwspec_get(dev) )
> return 0;
>
> + spin_lock(&dtdevs_lock);
> +
> /*
> * According to the Documentation/devicetree/bindings/iommu/iommu.txt
> * from Linux.
> @@ -157,7 +159,10 @@ int iommu_add_dt_device(struct dt_device_node *np)
> * these callback implemented.
> */
> if ( !ops->add_device || !ops->dt_xlate )
> - return -EINVAL;
> + {
> + rc = -EINVAL;
> + goto fail;
> + }
>
> if ( !dt_device_is_available(iommu_spec.np) )
> break;
> @@ -188,6 +193,8 @@ int iommu_add_dt_device(struct dt_device_node *np)
> if ( rc < 0 )
> iommu_fwspec_free(dev);
>
> +fail:
> + spin_unlock(&dtdevs_lock);
> return rc;
> }
>
>
