Vladimir Dergachev wrote: > > On Wed, 30 Jan 2002, Daryll Strauss wrote: > > > On Wed, Jan 30, 2002 at 02:05:42PM -0500, Vladimir Dergachev wrote: > > > Regardless of the way it is merged the driver major version will need to > > > be bumped. GATOS drivers does this but only minor - as I did not want to > > > upload a mesa radeon driver just because of the version change. > > > > I'm afraid I haven't been following this discussion closely enough, but > > I found this statement sort of odd, so I thought I'd comment. > > > > Version numbers for kernel interfaces are rather different than those > > for normal software packages. In normal software packages they are more > > of a vanity thing. A minor version number bump means small things > > changed, and a major one means hey we did big things. In kernel drivers > > they are really important as they describe the API between the kernel > > and the user space application. There are very strict rules about which > > version numbers are changed when. > > > > The major version of a driver should be incremented if and only if there > > are incompatible changes to the driver that prevent older versions from > > working. You obviously want to minimize these sorts of changes, so that > > you don't break compatability. For example, lets say we found a big > > security hole in an IOCTL. The first thing we'd try to do is rewrite the > > function so avoid the hole. Maybe even in a way that's really slow. As > > long as the interface remains the same that's fine. We might add a new > > interface that's fast again, but keep the old one around for backward > > compatability. If that's completely impossible then we remove the IOCTL > > and bump the major version number. > > > > If you add or change functionality, but the old drivers still work, then > > a minor version number should be bumped. Drivers will check for a > > matching major number and minor number that is greater than or equal to > > the one they need. So, again if we go back to that security problem. If > > we rewrote the old IOCTL to be slow but secure and added a new one that > > is safe and fast, the minor number would be bumped. > > > > If you just fix a bug or make some really small change that doesn't > > impact the interface, then you bump the third digit. Third digits are > > ignored by the software and are really just documentation. > > I completely agree with you.. but I did not give you details :)) > > What happens is that if you try to use older drm driver with GATOS 2d > driver the GATOS driver will notice and complain. But if you use GATOS drm > driver with older 4.2.0 2d driver you will get a lockup. > > The reason is that the changes involve programming Radeon's memory > controller to place AGP aperture after the end of the framebuffer and not > at the start of PCI space as it is done currently. Both 2d driver and drm > driver have to agree on this - which is why a bump in major version is > necessary.
This will never be accepted by Linus, Alan or any of the kernel people. You need to find a way to make existing (distributed) clients work with the new kernel modules. Major number bumps are essentially illegal - we've promised not to do this. I don't know how to achieve your changes under that restriction... Keith _______________________________________________ Dri-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/dri-devel
