Re: [PATCH v2] platform/x86: wmi: Use ACPI device name in netlink event

From: Ilpo Järvinen
Date: Mon Jan 22 2024 - 07:48:10 EST


On Mon, 22 Jan 2024, Hans de Goede wrote:
> On 1/21/24 21:08, Armin Wolf wrote:
> > The device name inside the ACPI netlink event is limited to
> > 15 characters, so the WMI device name will get truncated.
> >
> > This can be observed with kacpimon when receiving an event
> > from WMI device "9DBB5994-A997-11DA-B012-B622A1EF5492":
> >
> > netlink: 9DBB5994-A997- 000000d0 00000000
> >
> > Fix this by using the shorter device name from the ACPI
> > bus device instead. This still allows users to uniquely
> > identify the WMI device by using the notify id (0xd0).
> >
> > Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
> > ---
> > Changes since v1:
> > - use acpi_dev_name() helper function
>
> I'm a bit divided on this patch. I agree the new way of doing
> things is better, but technically this is a bit of a userspace API
> break.
>
> I guess we could hope that nothing depends on the old netlink API
> format / name but I'm not sure we can rely on that ...
>
> Ilpo, Andy do you have any opinion on this ?

Hi Armin,

Have you tried to conduct debian code search to find the code using this?

--
i.

> > ---
> > drivers/platform/x86/wmi.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c
> > index a7cfcbf92432..c61860db66ed 100644
> > --- a/drivers/platform/x86/wmi.c
> > +++ b/drivers/platform/x86/wmi.c
> > @@ -1202,7 +1202,7 @@ static int wmi_notify_device(struct device *dev, void *data)
> > }
> >
> > acpi_bus_generate_netlink_event(wblock->acpi_device->pnp.device_class,
> > - dev_name(&wblock->dev.dev), *event, 0);
> > + acpi_dev_name(wblock->acpi_device), *event, 0);
> >
> > return -EBUSY;
> > }
> > --
> > 2.39.2
> >
>