Re: [PATCH 2/5] firmware: arm_scmi: imx: Add i.MX95 CPU Protocol

Dan Carpenter
2025-01-22T12:41:46Z

On Wed, Jan 22, 2025 at 12:22:18PM +0000, Cristian Marussi wrote:
> > > +struct scmi_msg_imx_cpu_attributes_out {
> > > + __le32 attributes;
> > > +#define CPU_MAX_NAME 16
> > > + u8 name[CPU_MAX_NAME];
> >
> > char is always unsigned in the kernel these days but strings should
> > still always be char. Same thing in patch 1, there were a couple u8
> > names.
> >
>
> While it is certainly true that char is the way to go for strings and, as
> such, it is used elsewhere to hold the resource names across all SCMI
> protocols, in this context it is a field of structure representing
> exactly the layout of message reply coming from the server, and defined
> in the SCMI spec as a uint8 array, so, we have generally preferred to
> used u8 to represent such fixed size array all across the SCMI stack
> protocols implementation....
>
> .... not saying that it is necessarily completelt right, but that is the
> reason we are guilty :D

Fine. I don't have intense emotions about this.

It does slightly bother me when we assume that the SCMI server NUL
terminates these when we do things like:

dev_info(ph->dev, "i.MX CPU: name: %s\n", out->name);

But from a practical perspective we have to trust the SCMI server.

regards,
dan carpenter