On Wednesday 30 November 2011, Michael S. Tsirkin wrote: > On Wed, Nov 30, 2011 at 03:49:57PM +0000, Arnd Bergmann wrote: > > On Wednesday 30 November 2011, Michael S. Tsirkin wrote: > > > On Wed, Nov 30, 2011 at 02:04:41PM +0000, Arnd Bergmann wrote: > > > > > > > Ah, right. I didn't realize that the generic pci_iomap still attempts > > > > to call ioport_map(). It would probably make sense to enclose > > > > the ioport_map() call in pci_iomap() inside of #ifdef CONFIG_HAS_IOPORT. > > > > It's not exactly beautiful, but probably the most correct solution > > > > so that we can make any call to ioport_map() a build-time error on > > > > architectures that set CONFIG_NO_IOPORT. > > > > > > I'm not sure why do you want to do that. > > > > > > > The problem is that any definition of ioport_map on architectures > > that can't do it is potentially harmful. Calling panic() is > > bad style as you pointed out, but simply returning NULL can > > also be harmful because it's likely that some drivers are written > > under the (false) assumption that ioport_map can never fail. > > Getting a build-time error would be more helpful here IMHO. > > Yes but uglifying these users is also bad, ifdefs in code are incredibly > fragile. Isn't it enough to declare ioport_map __must_check? I guess we already wasted too many electrons over this triviality, I don't actually care all that much, and will probably have to touch the same code again when I get to submit my patch to make inb/outb optional for architectures. Just pick any solution (including your original one). I'll revisit this when I'm bothered by the presence of the ioport_map function and will keep you in the loop on those patches. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
