On Thu, Nov 24, 2016 at 12:20:19PM +0100, Marek Szyprowski wrote: > This patch adds default_domain check before calling > exynos_iommu_detach_device. This path was intended only to cope with > default domains, which are automatically attached by the iommu core, so > return error if user tries to attach device, which is already attached > to other (non-default) domain. > > Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> > --- > drivers/iommu/exynos-iommu.c | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c > index 426b1534d4d3..63d9358a6d9c 100644 > --- a/drivers/iommu/exynos-iommu.c > +++ b/drivers/iommu/exynos-iommu.c > @@ -859,8 +859,17 @@ static int exynos_iommu_attach_device(struct iommu_domain *iommu_domain, > if (!has_sysmmu(dev)) > return -ENODEV; > > - if (owner->domain) > + if (owner->domain) { > + struct iommu_group *group = iommu_group_get(dev); > + > + if (!group || > + owner->domain != iommu_group_default_domain(group)) { > + iommu_group_put(group); > + return -EINVAL; > + } > + iommu_group_put(group); > exynos_iommu_detach_device(owner->domain, dev); > + } Does this fix any actual bug? The iommu core should take care that the above never happens. See __iommu_attach_group() function for details. Joerg -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html