On Sun, Jun 3, 2012 at 6:05 PM, Bjorn Helgaas <bhelgaas@xxxxxxxxxx> wrote: > On Fri, Jun 1, 2012 at 4:30 PM, Yinghai Lu <yinghai@xxxxxxxxxx> wrote: >> On Tue, May 29, 2012 at 1:50 PM, H. Peter Anvin <hpa@xxxxxxxxx> wrote: >>> >>> The bus-side address space should not be more than 32 bits no matter >>> what. As Bjorn indicates, you seem to be mixing up bus and cpu >>> addresses all over the place. >> >> please check update patches that is using converted pci bus address >> for boundary checking. > > What problem does this fix? There's significant risk that this > allocation change will make us trip over something, so it must fix > something to make it worth considering. If we do not enable that, we would not find the problem. On one my test setup that _CRS does state 64bit resource range, but when I clear some device resource manually and let kernel allocate high, just then find out those devices does not work with drivers. It turns out _CRS have more big range than what the chipset setting states. with fixing in BIOS, allocate high is working now on that platform. > > Steve's problem doesn't count because that's a "pci=nocrs" case that > will always require special handling. but pci=nocrs is still supported, even some systems does not work with pci=use_crs > A general solution is not > possible without a BIOS change (to describe >4GB apertures) or a > native host bridge driver (to discover >4GB apertures from the > hardware). These patches only make Steve's machine work by accident > -- they make us put the video device above 4GB, and we're just lucky > that the host bridge claims that region. Some bios looks enabling the non-stated range default to legacy chain. Some bios does not do that. only stated range count. So with pci=nocrs we still have some chance to get allocate high working. > > One possibility is some sort of boot-time option to force a PCI device > to a specified address. That would be useful for debugging as well as > for Steve's machine. yeah, how about pci=alloc_high and default to disabled ? Thanks Yinghai -- 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
