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| author | Yuan Can <yuancan@huawei.com> | 2022-11-08 09:12:26 +0000 |
|---|---|---|
| committer | Robert Foss <robert.foss@linaro.org> | 2022-11-29 17:56:49 +0100 |
| commit | 4ecff954c370b82bce45bdca2846c5c5563e8a8a (patch) | |
| tree | def9f765aa90d65669655105b13fa361d5603c0c /drivers/gpu | |
| parent | 11ffff9284261235cac7c9a0956943e017fe1a9f (diff) | |
| download | linux-stable-4ecff954c370b82bce45bdca2846c5c5563e8a8a.tar.gz linux-stable-4ecff954c370b82bce45bdca2846c5c5563e8a8a.tar.bz2 linux-stable-4ecff954c370b82bce45bdca2846c5c5563e8a8a.zip | |
drm/bridge: megachips: Fix error handling in i2c_register_driver()
A problem about insmod megachips-stdpxxxx-ge-b850v3-fw.ko failed is
triggered with the following log given:
[ 4497.981497] Error: Driver 'stdp4028-ge-b850v3-fw' is already registered, aborting...
insmod: ERROR: could not insert module megachips-stdpxxxx-ge-b850v3-fw.ko: Device or resource busy
The reason is that stdpxxxx_ge_b850v3_init() returns i2c_add_driver()
directly without checking its return value, if i2c_add_driver() failed,
it returns without calling i2c_del_driver() on the previous i2c driver,
resulting the megachips-stdpxxxx-ge-b850v3-fw can never be installed
later.
A simple call graph is shown as below:
stdpxxxx_ge_b850v3_init()
i2c_add_driver(&stdp4028_ge_b850v3_fw_driver)
i2c_add_driver(&stdp2690_ge_b850v3_fw_driver)
i2c_register_driver()
driver_register()
bus_add_driver()
priv = kzalloc(...) # OOM happened
# return without delete stdp4028_ge_b850v3_fw_driver
Fix by calling i2c_del_driver() on stdp4028_ge_b850v3_fw_driver when
i2c_add_driver() returns error.
Fixes: fcfa0ddc18ed ("drm/bridge: Drivers for megachips-stdpxxxx-ge-b850v3-fw (LVDS-DP++)")
Signed-off-by: Yuan Can <yuancan@huawei.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Tested-by: Ian Ray <ian.ray@ge.com>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20221108091226.114524-1-yuancan@huawei.com
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/bridge/megachips-stdpxxxx-ge-b850v3-fw.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/gpu/drm/bridge/megachips-stdpxxxx-ge-b850v3-fw.c b/drivers/gpu/drm/bridge/megachips-stdpxxxx-ge-b850v3-fw.c index 97359f807bfc..cbfa05a6767b 100644 --- a/drivers/gpu/drm/bridge/megachips-stdpxxxx-ge-b850v3-fw.c +++ b/drivers/gpu/drm/bridge/megachips-stdpxxxx-ge-b850v3-fw.c @@ -440,7 +440,11 @@ static int __init stdpxxxx_ge_b850v3_init(void) if (ret) return ret; - return i2c_add_driver(&stdp2690_ge_b850v3_fw_driver); + ret = i2c_add_driver(&stdp2690_ge_b850v3_fw_driver); + if (ret) + i2c_del_driver(&stdp4028_ge_b850v3_fw_driver); + + return ret; } module_init(stdpxxxx_ge_b850v3_init); |