iommu: Don't overwrite domain pointer when there is no default_domain

IOMMU drivers that do not support default domains, but make
use of the the group->domain pointer can get that pointer
overwritten with NULL on device add/remove.

Make sure this can't happen by only overwriting the domain
pointer when it is NULL.

Cc: stable@vger.kernel.org # v4.4+
Fixes: 1228236de5 ('iommu: Move default domain allocation to iommu_group_get_for_dev()')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Joerg Roedel 2016-04-04 15:47:48 +02:00
parent 07b48ac4bb
commit eebb8034a5
1 changed files with 2 additions and 1 deletions

View File

@ -848,7 +848,8 @@ struct iommu_group *iommu_group_get_for_dev(struct device *dev)
if (!group->default_domain) {
group->default_domain = __iommu_domain_alloc(dev->bus,
IOMMU_DOMAIN_DMA);
group->domain = group->default_domain;
if (!group->domain)
group->domain = group->default_domain;
}
ret = iommu_group_add_device(group, dev);