Re: [PATCH v7 2/2] drivers/misc: Add Aspeed P2A control driver

From: Greg KH
Date: Wed Mar 27 2019 - 14:54:19 EST


On Wed, Mar 27, 2019 at 11:44:36AM -0700, Patrick Venture wrote:
> On Wed, Mar 27, 2019 at 11:28 AM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> >
> > On Tue, Mar 12, 2019 at 09:31:01AM -0700, Patrick Venture wrote:
> > > + phys_addr_t mem_base;
> >
> > Is this really a 32bit value?
>
> It's going to be a 32-bit value if this is in the dts for one of the
> correspondingly supported aspeed models.
>
> >
> > Your ioctl thinks it is:
> >
> > > +struct aspeed_p2a_ctrl_mapping {
> > > + __u32 addr;
> >
> > Does this driver not work on a 64bit kernel?
>
> This driver is aimed at only 32-bit hardware (ast2400/2500). I
> modeled the approach after the aspeed-lpc-ctrl driver as it's
> providing similar functionality.
>
> >
> > > + __u32 length;
> > > + __u32 flags;
> > > +};
> >
> > addr really should be __u32 here so you don't have to mess with 32/64
> > bit user/kernel issues, right?
>
> Add is __u32 there. Are you suggesting it shouldn't be?

Ugh, yes, sorry, I meant to say "__u64".

If you all insist that this is all that is ever going to be needed, ok,
but I reserve the right to complain in 4 years when this needs to be
changed :)

thanks,

greg k-h