Re: [PATCH] iommu: set group default domain before creating direct mappings

[Lu Baolu]

Hi,

On 12/11/19 2:56 AM, Jerry Snitselaar wrote:
> iommu_group_create_direct_mappings uses group->default_domain, but
> right after it is called, request_default_domain_for_dev calls
> iommu_domain_free for the default domain, and sets the group default
> domain to a different domain. Move the
> iommu_group_create_direct_mappings call to after the group default
> domain is set, so the direct mappings get associated with that domain.
>
> Cc: Joerg Roedel <jroedel@xxxxxxx>
> Cc: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>

This fix looks good to me.

Reviewed-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>

Best regards,
baolu

> Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: 7423e01741dd ("iommu: Add API to request DMA domain for device")
> Signed-off-by: Jerry Snitselaar <jsnitsel@xxxxxxxxxx>
> ---
>   drivers/iommu/iommu.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
> index db7bfd4f2d20..fa908179b80b 100644
> --- a/drivers/iommu/iommu.c
> +++ b/drivers/iommu/iommu.c
> @@ -2282,13 +2282,13 @@ request_default_domain_for_dev(struct device *dev, unsigned long type)
>   		goto out;
>   	}
>   
> -	iommu_group_create_direct_mappings(group, dev);
> -
>   	/* Make the domain the default for this group */
>   	if (group->default_domain)
>   		iommu_domain_free(group->default_domain);
>   	group->default_domain = domain;
>   
> +	iommu_group_create_direct_mappings(group, dev);
> +
>   	dev_info(dev, "Using iommu %s mapping\n",
>   		 type == IOMMU_DOMAIN_DMA ? "dma" : "direct");
>