On Tue, Jan 13, 2015 at 06:01:53PM +0100, Alexander Graf wrote: > On 01/13/15 17:17, Michael S. Tsirkin wrote: > >On Tue, Jan 13, 2015 at 05:54:46PM +0200, Michael S. Tsirkin wrote: > >>I think we already do this for PC: > >> commit 83d08f2673504a299194dcac1657a13754b5932a > >> Author: Michael S. Tsirkin <m...@redhat.com> > >> Date: Tue Oct 29 13:57:34 2013 +0100 > >> > >> pc: map PCI address space as catchall region for not mapped > >> addresses > >> > >>but we need to find and fix all other targets. > >BTW this is very easy to test. > >Add an unused device (like ivshmem) enable BAR, and set it to 0. > >System should survive, as opposed to hanging. > > > >But the big question is whether this is the right > >thing to do for each platform. > >For PIIX whatever is not system memory, is PCI. > >But other boxes might have a different view of the matter. > > Only few platforms have PCI mapped at 0, no? So in most cases you get > windows that simply don't have overlapping at all. > > > Alex
What's missing is complete analysis of the problem. Ideally testing on several targets. -- MST
