From: Phillip Potter <phil@xxxxxxxxxxxxxxxx> [ Upstream commit 4df2a8b0ad634d98a67e540a4e18a60f943e7d9f ] Place a comment in hidma_mgmt_init explaining why success must currently be assumed, due to the cleanup issue that would need to be considered were this module ever to be unloadable or were this platform_driver_register call ever to fail. Acked-By: Vinod Koul <vkoul@xxxxxxxxxx> Acked-By: Sinan Kaya <okaya@xxxxxxxxxx> Signed-off-by: Phillip Potter <phil@xxxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210503115736.2104747-52-gregkh@xxxxxxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/dma/qcom/hidma_mgmt.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/drivers/dma/qcom/hidma_mgmt.c b/drivers/dma/qcom/hidma_mgmt.c index 82f36e466083..143ea7cad756 100644 --- a/drivers/dma/qcom/hidma_mgmt.c +++ b/drivers/dma/qcom/hidma_mgmt.c @@ -398,6 +398,20 @@ static int __init hidma_mgmt_init(void) of_node_put(child); } #endif + /* + * We do not check for return value here, as it is assumed that + * platform_driver_register must not fail. The reason for this is that + * the (potential) hidma_mgmt_of_populate_channels calls above are not + * cleaned up if it does fail, and to do this work is quite + * complicated. In particular, various calls of of_address_to_resource, + * of_irq_to_resource, platform_device_register_full, of_dma_configure, + * and of_msi_configure which then call other functions and so on, must + * be cleaned up - this is not a trivial exercise. + * + * Currently, this module is not intended to be unloaded, and there is + * no module_exit function defined which does the needed cleanup. For + * this reason, we have to assume success here. + */ platform_driver_register(&hidma_mgmt_driver); return 0; -- 2.30.2
