Re: [PATCH 1/3] mic: vop: fix a written error in MODULE_DEVICE_TABLE

[Greg KH]

On Sun, Sep 27, 2020 at 12:19:50PM +0000, Sherry Sun wrote:
> Hi Greg,
> 
> > -----Original Message-----
> > From: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>
> > Sent: 2020年9月27日 18:29
> > To: Sherry Sun <sherry.sun@xxxxxxx>
> > Cc: sudeep.dutt@xxxxxxxxx; ashutosh.dixit@xxxxxxxxx; arnd@xxxxxxxx;
> > masahiroy@xxxxxxxxxx; michal.lkml@xxxxxxxxxxx; lee.jones@xxxxxxxxxx;
> > rikard.falkeborn@xxxxxxxxx; mst@xxxxxxxxx; bp@xxxxxxx;
> > jhugo@xxxxxxxxxxxxxx; tglx@xxxxxxxxxxxxx;
> > manivannan.sadhasivam@xxxxxxxxxx; mgross@xxxxxxxxxxxxxxx; pierre-
> > louis.bossart@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux-
> > kbuild@xxxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx>
> > Subject: Re: [PATCH 1/3] mic: vop: fix a written error in
> > MODULE_DEVICE_TABLE
> > 
> > On Fri, Sep 25, 2020 at 03:31:56PM +0800, Sherry Sun wrote:
> > > For vop bus, the first parameter should be vop in MODULE_DEVICE_TABLE.
> > >
> > > Signed-off-by: Sherry Sun <sherry.sun@xxxxxxx>
> > > Signed-off-by: Joakim Zhang <qiangqing.zhang@xxxxxxx>
> > > ---
> > >  drivers/misc/mic/vop/vop_main.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/misc/mic/vop/vop_main.c
> > > b/drivers/misc/mic/vop/vop_main.c index d609f0dc6124..589425fa78d4
> > > 100644
> > > --- a/drivers/misc/mic/vop/vop_main.c
> > > +++ b/drivers/misc/mic/vop/vop_main.c
> > > @@ -796,7 +796,7 @@ static struct vop_driver vop_driver = {
> > >
> > >  module_vop_driver(vop_driver);
> > >
> > > -MODULE_DEVICE_TABLE(mbus, id_table);
> > > +MODULE_DEVICE_TABLE(vop, id_table);
> > >  MODULE_AUTHOR("Intel Corporation");
> > >  MODULE_DESCRIPTION("Intel(R) Virtio Over PCIe (VOP) driver");
> > > MODULE_LICENSE("GPL v2");
> > 
> > Doesn't this have to go _after_ the MODULE_DEVICE_TABLE(vop...) support,
> > which you add in patch 2 of this series?
> 
> Yes, this patch must be used in conjunction with Patch2.
> But I think here may be a small bug, in order to distinguish it from the driver
> autoloading support, make this a separate patch.
> 
> I can put this patch together with Patch2 if you think it might look more reasonable.

How about _after_ patch 2, otherwise this patch will break the build,
right?

> > Does this patch here break the build?  If not, how is it working?
> > 
> > And if you only have one vop driver, why do you need autoloading for it?
> > 
> No, it doesn't break the build. But actually it won't work(autoloaded) when kernel boot and vop device appears.
> 
> Although we may only have one vop driver, but in the mic Kconfig, the intel mic/vop/cosm/scif drivers all
> recommended to be built as modules, if we don't add autoloading for them, we may need modprobe them
> one by one manually both on EP and RC side.
> 
> Obviously, for our use case, driver autoloading is more convenient.

Why are these all not "mic_SUFFIX" type drivers?  Why "vop" and "cosm"
and "scif"?

And if you only have 1 driver, then what would cause autoloading?

thanks,

greg k-h