Re: [PATCH] driver core: soc: remove layering violation for the soc_bus

From: Rafael J. Wysocki
Date: Mon Jan 30 2023 - 13:51:37 EST


On Mon, Jan 30, 2023 at 7:49 PM Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> The soc_bus code pokes around in the internal bus structures assuming
> that it "knows" if a field is not set that it has not been registered
> yet. That isn't a safe assumption, so just remove the layering
> violation entirely and keep track if the bus has been registered or not
> ourselves.
>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

> ---
> drivers/base/soc.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/base/soc.c b/drivers/base/soc.c
> index 22130b5f789d..0fb1d4ab9d8a 100644
> --- a/drivers/base/soc.c
> +++ b/drivers/base/soc.c
> @@ -30,6 +30,7 @@ struct soc_device {
> static struct bus_type soc_bus_type = {
> .name = "soc",
> };
> +static bool soc_bus_registered;
>
> static DEVICE_ATTR(machine, 0444, soc_info_show, NULL);
> static DEVICE_ATTR(family, 0444, soc_info_show, NULL);
> @@ -117,7 +118,7 @@ struct soc_device *soc_device_register(struct soc_device_attribute *soc_dev_attr
> const struct attribute_group **soc_attr_groups;
> int ret;
>
> - if (!soc_bus_type.p) {
> + if (!soc_bus_registered) {
> if (early_soc_dev_attr)
> return ERR_PTR(-EBUSY);
> early_soc_dev_attr = soc_dev_attr;
> @@ -183,6 +184,7 @@ static int __init soc_bus_register(void)
> ret = bus_register(&soc_bus_type);
> if (ret)
> return ret;
> + soc_bus_registered = true;
>
> if (early_soc_dev_attr)
> return PTR_ERR(soc_device_register(early_soc_dev_attr));
> --
> 2.39.1
>