commit bb17d110cb upstream.
driver_set_override() helper uses device_lock() so it should not be
called before rpmsg_register_device() (which calls device_register()).
Effect can be seen with CONFIG_DEBUG_MUTEXES:
DEBUG_LOCKS_WARN_ON(lock->magic != lock)
WARNING: CPU: 3 PID: 57 at kernel/locking/mutex.c:582 __mutex_lock+0x1ec/0x430
...
Call trace:
__mutex_lock+0x1ec/0x430
mutex_lock_nested+0x44/0x50
driver_set_override+0x124/0x150
qcom_glink_native_probe+0x30c/0x3b0
glink_rpm_probe+0x274/0x350
platform_probe+0x6c/0xe0
really_probe+0x17c/0x3d0
__driver_probe_device+0x114/0x190
driver_probe_device+0x3c/0xf0
...
Refactor the rpmsg_register_device() function to use two-step device
registering (initialization + add) and call driver_set_override() in
proper moment.
This moves the code around, so while at it also NULL-ify the
rpdev->driver_override in error path to be sure it won't be kfree()
second time.
Fixes: 42cd402b8f ("rpmsg: Fix kfree() of static memory on setting driver_override")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20220429195946.1061725-2-krzysztof.kozlowski@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>