[PATCH] iommu: Don't attach deferred device in iommu_group_do_dma_attach

From: Jerry Snitselaar
Date: Thu Jun 04 2020 - 03:31:49 EST


Attaching a deferred device should be delayed until dma api is called.

Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
Suggested-by: Joerg Roedel <jroedel@xxxxxxx>
Signed-off-by: Jerry Snitselaar <jsnitsel@xxxxxxxxxx>
---
If you already have thrown a patch together, then ignore this. Also
feel free to swap out the signed-off-by with your's since
this is more your patch than mine. You can put a reviewed-by
and tested-by instead for me.

drivers/iommu/iommu.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index b5ea203f6c68..d43120eb1dc5 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(domain, dev))
+ ret = __iommu_attach_device(domain, dev);
+
+ return ret;
}

static int __iommu_group_dma_attach(struct iommu_group *group)
--
2.24.0