6.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Robin Murphy robin.murphy@arm.com
[ Upstream commit 3832862eb9c4dfa0e80b2522bfaedbc8a43de97d ]
At the moment, if of_iommu_configure() allocates dev->iommu itself via iommu_fwspec_init(), then suffers a DT parsing failure, it cleans up the fwspec but leaves the empty dev_iommu hanging around. So far this is benign (if a tiny bit wasteful), but we'd like to be able to reason about dev->iommu having a consistent and unambiguous lifecycle. Thus make sure that the of_iommu cleanup undoes precisely whatever it did.
Signed-off-by: Robin Murphy robin.murphy@arm.com Reviewed-by: Jason Gunthorpe jgg@nvidia.com Link: https://lore.kernel.org/r/d219663a3f23001f23d520a883ac622d70b4e642.174075326... Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/iommu-priv.h | 2 ++ drivers/iommu/iommu.c | 2 +- drivers/iommu/of_iommu.c | 6 +++++- 3 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/iommu-priv.h b/drivers/iommu/iommu-priv.h index de5b54eaa8bf1..a5913c0b02a0a 100644 --- a/drivers/iommu/iommu-priv.h +++ b/drivers/iommu/iommu-priv.h @@ -17,6 +17,8 @@ static inline const struct iommu_ops *dev_iommu_ops(struct device *dev) return dev->iommu->iommu_dev->ops; }
+void dev_iommu_free(struct device *dev); + const struct iommu_ops *iommu_ops_from_fwnode(const struct fwnode_handle *fwnode);
static inline const struct iommu_ops *iommu_fwspec_ops(struct iommu_fwspec *fwspec) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 1efe7cddb4fe3..3a2804a98203b 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -352,7 +352,7 @@ static struct dev_iommu *dev_iommu_get(struct device *dev) return param; }
-static void dev_iommu_free(struct device *dev) +void dev_iommu_free(struct device *dev) { struct dev_iommu *param = dev->iommu;
diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c index 97987cd78da93..e10a68b5ffde1 100644 --- a/drivers/iommu/of_iommu.c +++ b/drivers/iommu/of_iommu.c @@ -116,6 +116,7 @@ static void of_pci_check_device_ats(struct device *dev, struct device_node *np) int of_iommu_configure(struct device *dev, struct device_node *master_np, const u32 *id) { + bool dev_iommu_present; int err;
if (!master_np) @@ -127,6 +128,7 @@ int of_iommu_configure(struct device *dev, struct device_node *master_np, mutex_unlock(&iommu_probe_device_lock); return 0; } + dev_iommu_present = dev->iommu;
/* * We don't currently walk up the tree looking for a parent IOMMU. @@ -147,8 +149,10 @@ int of_iommu_configure(struct device *dev, struct device_node *master_np, err = of_iommu_configure_device(master_np, dev, id); }
- if (err) + if (err && dev_iommu_present) iommu_fwspec_free(dev); + else if (err && dev->iommu) + dev_iommu_free(dev); mutex_unlock(&iommu_probe_device_lock);
if (!err && dev->bus)