This is a note to let you know that I've just added the patch titled iommu/omap: Register driver before setting IOMMU ops to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: iommu-omap-register-driver-before-setting-iommu-ops.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Thu Mar 22 14:57:32 CET 2018 From: Suman Anna <s-anna@xxxxxx> Date: Wed, 12 Apr 2017 00:21:26 -0500 Subject: iommu/omap: Register driver before setting IOMMU ops From: Suman Anna <s-anna@xxxxxx> [ Upstream commit abaa7e5b054aae567861628b74dbc7fbf8ed79e8 ] Move the registration of the OMAP IOMMU platform driver before setting the IOMMU callbacks on the platform bus. This causes the IOMMU devices to be probed first before the .add_device() callback is invoked for all registered devices, and allows the iommu_group support to be added to the OMAP IOMMU driver. While at this, also check for the return status from bus_set_iommu. Signed-off-by: Suman Anna <s-anna@xxxxxx> Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/iommu/omap-iommu.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) --- a/drivers/iommu/omap-iommu.c +++ b/drivers/iommu/omap-iommu.c @@ -1295,6 +1295,7 @@ static int __init omap_iommu_init(void) const unsigned long flags = SLAB_HWCACHE_ALIGN; size_t align = 1 << 10; /* L2 pagetable alignement */ struct device_node *np; + int ret; np = of_find_matching_node(NULL, omap_iommu_of_match); if (!np) @@ -1308,11 +1309,25 @@ static int __init omap_iommu_init(void) return -ENOMEM; iopte_cachep = p; - bus_set_iommu(&platform_bus_type, &omap_iommu_ops); - omap_iommu_debugfs_init(); - return platform_driver_register(&omap_iommu_driver); + ret = platform_driver_register(&omap_iommu_driver); + if (ret) { + pr_err("%s: failed to register driver\n", __func__); + goto fail_driver; + } + + ret = bus_set_iommu(&platform_bus_type, &omap_iommu_ops); + if (ret) + goto fail_bus; + + return 0; + +fail_bus: + platform_driver_unregister(&omap_iommu_driver); +fail_driver: + kmem_cache_destroy(iopte_cachep); + return ret; } subsys_initcall(omap_iommu_init); /* must be ready before omap3isp is probed */ Patches currently in stable-queue which might be from s-anna@xxxxxx are queue-4.4/iommu-omap-register-driver-before-setting-iommu-ops.patch