Re: [PATCH 1/2] iommu/tegra: Add support for struct iommu_device

[Joerg Roedel <joro@8bytes.org>]

Hi Jon,

On Wed, Aug 30, 2017 at 03:22:05PM +0100, Jon Hunter wrote:
> Yes I can confirm that this fixes the crash. I assume that you will fix
> the error path for bus_set_iommu() above as I believe now it needs to
> call iommu_device_sysfs_remove().

Thanks for testing the patch. I updated the error-path and put the
commit below into the iommu-tree:

>From 96302d89a03524e04d46ec82c6730881bb755923 Mon Sep 17 00:00:00 2001
From: Joerg Roedel <jroedel@suse.de>
Date: Wed, 30 Aug 2017 15:06:43 +0200
Subject: [PATCH] arm/tegra: Call bus_set_iommu() after iommu_device_register()

The bus_set_iommu() function will call the add_device()
call-back which needs the iommu to be registered.

Reported-by: Jon Hunter <jonathanh@nvidia.com>
Fixes: 0b480e447006 ('iommu/tegra: Add support for struct iommu_device')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
 drivers/iommu/tegra-smmu.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index 2802e12e6a54..3b6449e2cbf1 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -949,10 +949,6 @@ struct tegra_smmu *tegra_smmu_probe(struct device *dev,
 
 	tegra_smmu_ahb_enable();
 
-	err = bus_set_iommu(&platform_bus_type, &tegra_smmu_ops);
-	if (err < 0)
-		return ERR_PTR(err);
-
 	err = iommu_device_sysfs_add(&smmu->iommu, dev, NULL, dev_name(dev));
 	if (err)
 		return ERR_PTR(err);
@@ -965,6 +961,13 @@ struct tegra_smmu *tegra_smmu_probe(struct device *dev,
 		return ERR_PTR(err);
 	}
 
+	err = bus_set_iommu(&platform_bus_type, &tegra_smmu_ops);
+	if (err < 0) {
+		iommu_device_unregister(&smmu->iommu);
+		iommu_device_sysfs_remove(&smmu->iommu);
+		return ERR_PTR(err);
+	}
+
 	if (IS_ENABLED(CONFIG_DEBUG_FS))
 		tegra_smmu_debugfs_init(smmu);
 
-- 
2.13.5