Re: [PATCH v7 1/2] module: add SCMI device table alias support

[Daniel Lezcano]

On 9/18/26 12:02, Hans de Goede wrote:
> Hi Daniel,
>
> On 18-Sep-26 11:53, Daniel Lezcano wrote:
> > Hi Hans,
> >
> > thanks for taking care of that
> >
> >
> > On 9/18/26 11:29, Hans de Goede wrote:
> > > From: Bjorn Andersson <bjorn.andersson@xxxxxxxxxxxxxxxx>
> > >
> > > SCMI client drivers already describe their bus match data with
> > > MODULE_DEVICE_TABLE(scmi, ...), but modpost does not know how to consume
> > > SCMI device tables. As a result, SCMI modules do not get generated module
> > > aliases from their id tables.
> > >
> > > Move struct scmi_device_id to mod_devicetable.h so it has a fixed layout
> > > visible to modpost, add the corresponding generated offsets and teach
> > > file2alias to emit scmi:<protocol>:<name> aliases.
> > >
> > > Use the same stable alias format for SCMI device uevents and sysfs
> > > modaliases. The previous string included the instance-specific device
> > > name, which is not useful for matching modules.
> > >
> > > Assisted-by: Codex:GPT-5.5
> > > Reviewed-by: Hans de Goede <johannes.goede@xxxxxxxxxxxxxxxx>
> > > Tested-by: Hans de Goede <johannes.goede@xxxxxxxxxxxxxxxx>
> > > Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxxxxxxxx>
> > > Signed-off-by: Hans de Goede <johannes.goede@xxxxxxxxxxxxxxxx>
> > > ---

[ ... ]

> > >    #include <linux/bitfield.h>
> > > +#include <linux/device-id/scmi.h>
> > >    #include <linux/device.h>
> > >    #include <linux/notifier.h>
> > >    #include <linux/types.h>
> > > @@ -951,11 +952,6 @@ struct scmi_device {
> > >      #define to_scmi_dev(d) container_of_const(d, struct scmi_device, dev)
> > >    -struct scmi_device_id {
> > > -    u8 protocol_id;
> > > -    const char *name;
> > > -};
> > > -
> >
> > What is the reason of converting the char * to a fixed array? That limits the name and may result in truncation and potentially name collision, no ?
>
> Because of how modpost works to generate modaliases inside the .ko
> any string buffers in device_id structs need to have a fixed length.
>
> So the truncation / name collision issue pretty much applies to all
> foo_device_id structs in the kernel. People should now to make sure
> that any strings used will fit inside the fixed string. And I would
> expect the compiler to warn for overly long strings.
Ok, thanks for the clarification