| Message ID | 20231128173823.867512-4-u.kleine-koenig@pengutronix.de |
|---|---|
| State | New |
| Headers | show |
| Series | None | expand |
On 28/11/2023 19:38, Uwe Kleine-König wrote: > The .remove() callback for a platform driver returns an int which makes > many driver authors wrongly assume it's possible to do error handling by > returning an error code. However the value returned is ignored (apart > from emitting a warning) and this typically results in resource leaks. > > To improve here there is a quest to make the remove callback return > void. In the first step of this quest all drivers are converted to > .remove_new(), which already returns void. Eventually after all drivers > are converted, .remove_new() will be renamed to .remove(). > > Replace the error path returning a non-zero value by an error message > and a comment that there is more to do. With that this patch results in > no change of behaviour in this driver apart from improving the error > message. > > Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Roger Quadros <rogerq@kernel.org>
diff --git a/drivers/net/ethernet/ti/cpsw_new.c b/drivers/net/ethernet/ti/cpsw_new.c index 0e4f526b1753..498c50c6d1a7 100644 --- a/drivers/net/ethernet/ti/cpsw_new.c +++ b/drivers/net/ethernet/ti/cpsw_new.c @@ -2037,14 +2037,20 @@ static int cpsw_probe(struct platform_device *pdev) return ret; } -static int cpsw_remove(struct platform_device *pdev) +static void cpsw_remove(struct platform_device *pdev) { struct cpsw_common *cpsw = platform_get_drvdata(pdev); int ret; ret = pm_runtime_resume_and_get(&pdev->dev); - if (ret < 0) - return ret; + if (ret < 0) { + /* Note, if this error path is taken, we're leaking some + * resources. + */ + dev_err(&pdev->dev, "Failed to resume device (%pe)\n", + ERR_PTR(ret)); + return; + } cpsw_unregister_notifiers(cpsw); cpsw_unregister_devlink(cpsw); @@ -2055,7 +2061,6 @@ static int cpsw_remove(struct platform_device *pdev) cpsw_remove_dt(cpsw); pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev); - return 0; } static int __maybe_unused cpsw_suspend(struct device *dev) @@ -2116,7 +2121,7 @@ static struct platform_driver cpsw_driver = { .of_match_table = cpsw_of_mtable, }, .probe = cpsw_probe, - .remove = cpsw_remove, + .remove_new = cpsw_remove, }; module_platform_driver(cpsw_driver);
The .remove() callback for a platform driver returns an int which makes many driver authors wrongly assume it's possible to do error handling by returning an error code. However the value returned is ignored (apart from emitting a warning) and this typically results in resource leaks. To improve here there is a quest to make the remove callback return void. In the first step of this quest all drivers are converted to .remove_new(), which already returns void. Eventually after all drivers are converted, .remove_new() will be renamed to .remove(). Replace the error path returning a non-zero value by an error message and a comment that there is more to do. With that this patch results in no change of behaviour in this driver apart from improving the error message. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> --- drivers/net/ethernet/ti/cpsw_new.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-)