From 386dce2788eef626aaaa6a3ca32809ea7904581b Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Thu, 19 Dec 2019 12:03:42 +0000 Subject: iommu/of: Take a ref to the IOMMU driver during ->of_xlate() Ensure that we hold a reference to the IOMMU driver module while calling the '->of_xlate()' callback during early device probing. Signed-off-by: Will Deacon Tested-by: John Garry # smmu v3 Reviewed-by: Greg Kroah-Hartman Signed-off-by: Joerg Roedel --- drivers/iommu/of_iommu.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c index 4d2f02132e7a..e7bc8b721947 100644 --- a/drivers/iommu/of_iommu.c +++ b/drivers/iommu/of_iommu.c @@ -8,11 +8,12 @@ #include #include #include -#include +#include #include #include #include #include +#include #include #include @@ -91,16 +92,16 @@ static int of_iommu_xlate(struct device *dev, { const struct iommu_ops *ops; struct fwnode_handle *fwnode = &iommu_spec->np->fwnode; - int err; + int ret; ops = iommu_ops_from_fwnode(fwnode); if ((ops && !ops->of_xlate) || !of_device_is_available(iommu_spec->np)) return NO_IOMMU; - err = iommu_fwspec_init(dev, &iommu_spec->np->fwnode, ops); - if (err) - return err; + ret = iommu_fwspec_init(dev, &iommu_spec->np->fwnode, ops); + if (ret) + return ret; /* * The otherwise-empty fwspec handily serves to indicate the specific * IOMMU device we're waiting for, which will be useful if we ever get @@ -109,7 +110,12 @@ static int of_iommu_xlate(struct device *dev, if (!ops) return driver_deferred_probe_check_state(dev); - return ops->of_xlate(dev, iommu_spec); + if (!try_module_get(ops->owner)) + return -ENODEV; + + ret = ops->of_xlate(dev, iommu_spec); + module_put(ops->owner); + return ret; } struct of_pci_iommu_alias_info { -- cgit v1.2.3