This is a note to let you know that I've just added the patch titled media: platform: exynos4-is: Fix error handling in fimc_md_init() to the 5.4-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: media-platform-exynos4-is-fix-error-handling-in-fimc.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 6d07c4d191b280cd1f10aa533355fc36c1d177b2 Author: Yuan Can <yuancan@xxxxxxxxxx> Date: Fri Nov 11 06:08:53 2022 +0000 media: platform: exynos4-is: Fix error handling in fimc_md_init() [ Upstream commit b434422c45282a0573d8123239abc41fa72665d4 ] A problem about modprobe s5p_fimc failed is triggered with the following log given: [ 272.075275] Error: Driver 'exynos4-fimc' is already registered, aborting... modprobe: ERROR: could not insert 's5p_fimc': Device or resource busy The reason is that fimc_md_init() returns platform_driver_register() directly without checking its return value, if platform_driver_register() failed, it returns without unregister fimc_driver, resulting the s5p_fimc can never be installed later. A simple call graph is shown as below: fimc_md_init() fimc_register_driver() # register fimc_driver platform_driver_register() platform_driver_register() driver_register() bus_add_driver() dev = kzalloc(...) # OOM happened # return without unregister fimc_driver Fix by unregister fimc_driver when platform_driver_register() returns error. Fixes: d3953223b090 ("[media] s5p-fimc: Add the media device driver") Signed-off-by: Yuan Can <yuancan@xxxxxxxxxx> Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/media/platform/exynos4-is/fimc-core.c b/drivers/media/platform/exynos4-is/fimc-core.c index cde60fbb23a8..5b06c83f5c99 100644 --- a/drivers/media/platform/exynos4-is/fimc-core.c +++ b/drivers/media/platform/exynos4-is/fimc-core.c @@ -1231,7 +1231,7 @@ int __init fimc_register_driver(void) return platform_driver_register(&fimc_driver); } -void __exit fimc_unregister_driver(void) +void fimc_unregister_driver(void) { platform_driver_unregister(&fimc_driver); } diff --git a/drivers/media/platform/exynos4-is/media-dev.c b/drivers/media/platform/exynos4-is/media-dev.c index a07d796f63df..707feb35a950 100644 --- a/drivers/media/platform/exynos4-is/media-dev.c +++ b/drivers/media/platform/exynos4-is/media-dev.c @@ -1581,7 +1581,11 @@ static int __init fimc_md_init(void) if (ret) return ret; - return platform_driver_register(&fimc_md_driver); + ret = platform_driver_register(&fimc_md_driver); + if (ret) + fimc_unregister_driver(); + + return ret; } static void __exit fimc_md_exit(void)