Re: [PATCH] virt: sev-guest: Mark driver struct with __refdata to prevent section mismatch

[Tom Lendacky <thomas.lendacky@amd.com>]

On 3/29/24 16:54, Uwe Kleine-König wrote:
> As described in the added code comment, a reference to .exit.text is ok
> for drivers registered via module_platform_driver_probe(). Make this
> explicit to prevent the following section mismatch warning
> 
> 	WARNING: modpost: drivers/virt/coco/sev-guest/sev-guest: section mismatch in reference: sev_guest_driver+0x10 (section: .data) -> sev_guest_remove (section: .exit.text)
> 
> that triggers on an allmodconfig W=1 build.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>

> ---
>   drivers/virt/coco/sev-guest/sev-guest.c | 7 ++++++-
>   1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/virt/coco/sev-guest/sev-guest.c b/drivers/virt/coco/sev-guest/sev-guest.c
> index 87f241825bc3..1af68065b3d9 100644
> --- a/drivers/virt/coco/sev-guest/sev-guest.c
> +++ b/drivers/virt/coco/sev-guest/sev-guest.c
> @@ -1009,8 +1009,13 @@ static void __exit sev_guest_remove(struct platform_device *pdev)
>    * This driver is meant to be a common SEV guest interface driver and to
>    * support any SEV guest API. As such, even though it has been introduced
>    * with the SEV-SNP support, it is named "sev-guest".
> + *
> + * sev_guest_remove() lives in .exit.text. For drivers registered via
> + * module_platform_driver_probe() this is ok because they cannot get unbound at
> + * runtime. So mark the driver struct with __refdata to prevent modpost
> + * triggering a section mismatch warning.
>    */
> -static struct platform_driver sev_guest_driver = {
> +static struct platform_driver sev_guest_driver __refdata = {
>   	.remove_new	= __exit_p(sev_guest_remove),
>   	.driver		= {
>   		.name = "sev-guest",
> base-commit: a6bd6c9333397f5a0e2667d4d82fef8c970108f2