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Subject: Re: [virtio] [PATCH v2] transitional issues: add new IDs for all devices
"Michael S. Tsirkin" <firstname.lastname@example.org> writes: > non-transitional devices should have been able to simply update > revision ID to make sure legacy drivers are not loaded. > Unfortunately, mistakes were made: > - we didn't stress that drivers must check revision ID, > and of course there's no easy way for drivers to > test this failure path, > so older versions of Windows drivers ignored revision > (latest vision matches revision correctly) > - CCW lacks revision ID field > > Both facts mean a non-transitional device would need > a separate mechanism to prevent legacy drivers from > loading. > We aren't running out of device IDs yet, so > let's use up some to resolve this. > > I incremented all IDs by 0x100 intentionally - > for the PCI bindings, this should help remind people they can't > just stick the Subsystem ID into the low byte of the Device ID. > > Signed-off-by: Michael S. Tsirkin <email@example.com> OK, the only real proble I have with this is that you should remove the 0x1, 0x2 from the non-legacy section. > +Non-transitional devices must use the larger of the IDs. > +For example use Device ID=0x101 for a network card. > + > +Both transitional and non-transitional drivers must match all > +IDs for a given device type. The last one doesn't make sense. Non-transitional drivers should only care about 0x10x. That would be achieved by not listing the smaller numbers outside the Legacy Interface section. And anyway, we don't want the non-legacy implementers to have to read the legacy section. Cheers, Rusty.