On Thu, 2013-10-10 at 03:01 -0500, Bhushan Bharat-R65777 wrote: > > > -----Original Message----- > > From: kvm-owner@xxxxxxxxxxxxxxx [mailto:kvm-owner@xxxxxxxxxxxxxxx] On Behalf Of > > Kim Phillips > > Sent: Thursday, October 10, 2013 8:36 AM > > To: Wood Scott-B07421 > > Cc: Yoder Stuart-B08248; Wood Scott-B07421; christoffer.dall@xxxxxxxxxx; > > alex.williamson@xxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > > a.motakis@xxxxxxxxxxxxxxxxxxxxxx; agraf@xxxxxxx; Sethi Varun-B16395; Bhushan > > Bharat-R65777; peter.maydell@xxxxxxxxxx; santosh.shukla@xxxxxxxxxx; > > kvm@xxxxxxxxxxxxxxx; gregkh@xxxxxxxxxxxxxxxxxxx > > Subject: Re: RFC: (re-)binding the VFIO platform driver to a platform device > > > > On Wed, 9 Oct 2013 15:03:19 -0500 > > Scott Wood <scottwood@xxxxxxxxxxxxx> wrote: > > > > > On Wed, 2013-10-09 at 14:44 -0500, Yoder Stuart-B08248 wrote: > > > > > From: Wood Scott-B07421 > > > > > Sent: Wednesday, October 09, 2013 2:22 PM > > > > > > > > > > On Wed, 2013-10-09 at 14:02 -0500, Yoder Stuart-B08248 wrote: > > > > > > Have been thinking about this issue some more. As Scott > > > > > > mentioned, > > > > thanks for bringing this up again. > > > > > > > There's already a "bool suppress_bind_attrs" to prevent sysfs > > > > > bind/unbind. I suggested a similar flag to mean the oppsosite -- > > > > > bind > > > > > *only* through sysfs. Greg KH was skeptical and wanted to see a > > > > > patch before any further discussion. > > > > > > > > Ah, think I understand now...yes that works as well, and would be > > > > less intrustive. So are you writing a patch? :) > > > > > > I've been meaning to since the previous round of discussion, but I've > > > been busy. Would someone else be able to test it in the context of > > > using it for VFIO? > > > > yes - see below. > > > > > Otherwise, that looks about right, for the driver side (though > > > driver_attach could error out earlier rather than testing it inside > > > the loop). > > > > I've made the changes you suggested and tested the resulting diff below on an > > arndale board. I successfully performed the following sequence of commands > > after first changing the i2c@12C80000 node in the device tree to be exclusively > > compatible with "vfio": This is not the intended usage. Leave the device tree alone, add a wildcard option to platform_match() and use it in VFIO, and set drv->sysfs_bind_only in VFIO. > > diff --git a/drivers/base/bus.c b/drivers/base/bus.c index 73f6c29..da81442 > > 100644 > > --- a/drivers/base/bus.c > > +++ b/drivers/base/bus.c > > @@ -201,7 +201,8 @@ static ssize_t bind_store(struct device_driver *drv, const > > char *buf, > > int err = -ENODEV; > > > > dev = bus_find_device_by_name(bus, NULL, buf); > > - if (dev && dev->driver == NULL && driver_match_device(drv, dev)) { > > + if (dev && dev->driver == NULL && (drv->sysfs_bind_only || > > + driver_match_device(drv, dev))) { > > Should not we check > if (dev && dev->driver == NULL && > (device->explicit_bind_only && drv->explicit_bind_only) || > driver_match_device(drv, dev))) device->sysfs_bind_only would be a separate patch. As for drv->sysfs_bind_only, that does not override driver_match_device(). Wildcard matches are separate and are handled by individual bus match functions. This function does not need to be changed at all for drv->sysfs_bind_only. -Scott -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
