Linux Virtualization - Jun 2020 - [PATCH v2 00/33] iommu: Move iommu_group setup to IOMMU core code

Hi Jerry,

On Mon, Jun 01, 2020 at 05:02:36PM -0700, Jerry Snitselaar
wrote:
> 
> Yeah, that will solve the panic.
>
If you still see the kdump faults, can you please try with the attached
diff? I was not able to reproduce them in my setup.

Regards,

	Joerg

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index b5ea203f6c68..5a6d509f72b6 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1680,8 +1680,12 @@ static void probe_alloc_default_domain(struct bus_type
*bus,
 static int iommu_group_do_dma_attach(struct device *dev, void *data)
 {
 	struct iommu_domain *domain = data;
+	int ret = 0;
 
-	return __iommu_attach_device(domain, dev);
+	if (!iommu_is_attach_deferred(group->domain, dev))
+		ret = __iommu_attach_device(group->domain, dev);
+
+	return ret;
 }
 
 static int __iommu_group_dma_attach(struct iommu_group *group)