> Is it a really a bug in X, or a misunderstanding between X and > the kernel as to what existence of the legacy_mem file implies? > > I may have got this quite wrong, but to me it appears that X assumes > that existence of the legacy_mem file implies that it will be useful; > whereas the kernel thinks it can make the legacy_mem file available, > even if it cannot be used for mmapping mem - which is its sole purpose? > > What if pci_create_legacy_files() were to call some new verification > routine, and only create the legacy_mem file if it would be usable? > (But perhaps that cannot be known at the time it needs to be created.) Well, first X should certainly not -fail- to launch if it fails to map legacy memory, which is generally not useful anyway. That's where the bug is. Jesse, did you have a chance to fix that yet or should I give it a go ? The second problem is that if I just don't expose the legacy_mem file, then X has no way to know whether the kernel doesn't support the interface or whether the HW doesn't support legacy memory access. So X will fallback to whacking /dev/mem which is even more bogus. At least that's what I remember from last I looked at that part of X code. It should be a trivial fix on X side tho. Cheers, Ben. -- To unsubscribe from this list: send the line "unsubscribe kernel-testers" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
