When two masters share an IOMMU, calling ops->of_xlate during the second master's driver init may overwrite iommu->domain set by the first. This causes the check if (iommu->domain == domain) in rk_iommu_attach_device() to fail, resulting in the same iommu->node being added twice to &rk_domain->iommus, which can lead to an infinite loop in subsequent &rk_domain->iommus operations.

Cc: stable@vger.kernel.org Fixes: 25c2325575cc ("iommu/rockchip: Add missing set_platform_dma_ops callback") Signed-off-by: Simon Xue xxm@rock-chips.com Reviewed-by: Robin Murphy robin.murphy@arm.com

v3: Add missing `Cc: stable@vger.kernel.org` in commit message. No functional changes. v2: No functional changes. --- drivers/iommu/rockchip-iommu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c index 22f74ba33a0e..e6bb3c784017 100644 --- a/drivers/iommu/rockchip-iommu.c +++ b/drivers/iommu/rockchip-iommu.c @@ -1157,7 +1157,6 @@ static int rk_iommu_of_xlate(struct device *dev, return -ENOMEM;

data->iommu = platform_get_drvdata(iommu_dev); - data->iommu->domain = &rk_identity_domain; dev_iommu_priv_set(dev, data);

platform_device_put(iommu_dev); @@ -1195,6 +1194,8 @@ static int rk_iommu_probe(struct platform_device *pdev) if (!iommu) return -ENOMEM;

+ iommu->domain = &rk_identity_domain; + platform_set_drvdata(pdev, iommu); iommu->dev = dev; iommu->num_mmu = 0;