Re: [PATCH 2/2] virt: sev-guest: Convert to platform remove callback returning void

[Tom Lendacky]

On 12/26/23 07:28, 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().
>
> Trivially convert this driver from always returning zero in the remove
> callback to the void returning variant.
>
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>

Acked-by: Tom Lendacky <thomas.lendacky@xxxxxxx>

> ---
>   drivers/virt/coco/sev-guest/sev-guest.c | 6 ++----
>   1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/virt/coco/sev-guest/sev-guest.c b/drivers/virt/coco/sev-guest/sev-guest.c
> index bc564adcf499..87f241825bc3 100644
> --- a/drivers/virt/coco/sev-guest/sev-guest.c
> +++ b/drivers/virt/coco/sev-guest/sev-guest.c
> @@ -994,7 +994,7 @@ static int __init sev_guest_probe(struct platform_device *pdev)
>   	return ret;
>   }
>   
> -static int __exit sev_guest_remove(struct platform_device *pdev)
> +static void __exit sev_guest_remove(struct platform_device *pdev)
>   {
>   	struct snp_guest_dev *snp_dev = platform_get_drvdata(pdev);
>   
> @@ -1003,8 +1003,6 @@ static int __exit sev_guest_remove(struct platform_device *pdev)
>   	free_shared_pages(snp_dev->request, sizeof(struct snp_guest_msg));
>   	deinit_crypto(snp_dev->crypto);
>   	misc_deregister(&snp_dev->misc);
> -
> -	return 0;
>   }
>   
>   /*
> @@ -1013,7 +1011,7 @@ static int __exit sev_guest_remove(struct platform_device *pdev)
>    * with the SEV-SNP support, it is named "sev-guest".
>    */
>   static struct platform_driver sev_guest_driver = {
> -	.remove		= __exit_p(sev_guest_remove),
> +	.remove_new	= __exit_p(sev_guest_remove),
>   	.driver		= {
>   		.name = "sev-guest",
>   	},