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(). Instead of returning an error code, emit a better error message than the core. Apart from the improved error message this patch has no effects for the driver. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx> --- Hello, I tried to improve this driver before, see https://lore.kernel.org/linux-acpi/CAJZ5v0ifb-wvyp0JRq_4c1L6vTi_qEeXJ6P=Pmmq_56xRL74_A@xxxxxxxxxxxxxx https://lore.kernel.org/linux-arm-kernel/20221219221439.1681770-1-u.kleine-koenig@xxxxxxxxxxxxxx https://lore.kernel.org/linux-arm-kernel/20221220154447.12341-1-u.kleine-koenig@xxxxxxxxxxxxxx but this didn't result in any patch being applied. I think it's inarguable that there is a problem that wants to be fixed. My tries to fix this problem fixxled out, so here comes a minimal change that just points out the problem and otherwise makes ghes_remove() return void without further side effects to allow me to continue my quest to make platform_driver remove callbacks return no error. Best regards Uwe drivers/acpi/apei/ghes.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index 63ad0541db38..dd8cd10b7809 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -1438,7 +1438,7 @@ static int ghes_probe(struct platform_device *ghes_dev) return rc; } -static int ghes_remove(struct platform_device *ghes_dev) +static void ghes_remove(struct platform_device *ghes_dev) { int rc; struct ghes *ghes; @@ -1475,8 +1475,15 @@ static int ghes_remove(struct platform_device *ghes_dev) break; case ACPI_HEST_NOTIFY_SOFTWARE_DELEGATED: rc = apei_sdei_unregister_ghes(ghes); - if (rc) - return rc; + if (rc) { + /* + * Returning early results in a resource leak, but we're + * only here if stopping the hardware failed. + */ + dev_err(&ghes_dev->dev, "Failed to unregister ghes (%pe)\n", + ERR_PTR(rc)); + return; + } break; default: BUG(); @@ -1490,8 +1497,6 @@ static int ghes_remove(struct platform_device *ghes_dev) mutex_unlock(&ghes_devs_mutex); kfree(ghes); - - return 0; } static struct platform_driver ghes_platform_driver = { @@ -1499,7 +1504,7 @@ static struct platform_driver ghes_platform_driver = { .name = "GHES", }, .probe = ghes_probe, - .remove = ghes_remove, + .remove_new = ghes_remove, }; void __init acpi_ghes_init(void) base-commit: 5a82d69d48c82e89aef44483d2a129f869f3506a -- 2.42.0
