Re: [PATCH RFC] pci: expose function reset capability in sysfs

[Jesse Barnes <jbarnes@virtuousgeek.org>]

On Mon, 27 Jul 2009 09:14:23 -0700
Greg KH <greg@kroah.com> wrote:

> On Mon, Jul 27, 2009 at 06:52:38PM +0300, Michael S. Tsirkin wrote:
> > On Mon, Jul 27, 2009 at 08:01:46AM -0700, Greg KH wrote:
> > > > +	if (!pci_probe_reset_function(dev)) {
> > > > +		retval = device_create_file(&dev->dev,
> > > > &reset_attr);
> > > > +		if (retval)
> > > > +			goto error;
> > > > +	}
> > > 
> > > So you only add the file if there is a reset function, which is
> > > fine, but later on:
> > > 
> > > > @@ -1037,6 +1073,7 @@ static void
> > > > pci_remove_capabilities_sysfs(struct pci_dev *dev) }
> > > >  
> > > >  	pcie_aspm_remove_sysfs_dev_files(dev);
> > > > +	device_remove_file(&dev->dev, &reset_attr);
> > > 
> > > You always remove the file, if it has been created or not.  That
> > > could cause problems in the future, please only remove a file if
> > > you have actually added it to the sysfs tree.
> > > 
> > > thanks,
> > > 
> > > greg k-h
> > 
> > OK. I think, however, that it's better to avoid probing the function
> > on cleanup path just to figure out whether the file needs to be
> > removed. Can this info be stored in struct pci_dev?
> > Along the lines of:
> 
> Fine with me.  You forgot the documentation though :)

Aside from vague worries about encouraging more userland drivers, this
seems like a reasonable feature to me (and certainly no more
encouraging than our current set of config and resource files).

-- 
Jesse Barnes, Intel Open Source Technology Center