On Thu, Jul 25, 2013 at 1:35 PM, Bjorn Helgaas <bhelgaas@xxxxxxxxxx> wrote: > On Thu, Jul 25, 2013 at 7:31 AM, Yinghai Lu <yinghai@xxxxxxxxxx> wrote: >> BenH reported that there are assign unassigned resource problems >> in powerpc. >> >> It turns out after >> | commit 0c5be0cb0edfe3b5c4b62eac68aa2aa15ec681af >> | Date: Thu Feb 23 19:23:29 2012 -0800 >> | >> | PCI: Retry on IORESOURCE_IO type allocations >> >> even for root bus that does not have io port range, it will keep retrying >> to realloc with mmio after mmio allocation work in first try already. >> >> Current retry logic is : try with must+optional at first, and if >> it fails with any ioport or mmio, it will try must then try to extend >> must with optional. The reassign will put extended mmio or pref mmio >> in the middle of parent resource range. >> That will prevent other sibling resources from getting must-have resources >> or get extended properly. >> >> We can check fail type to see if can we need fall back to must-have >> for it only, that will keep others type to keep resource to have >> must+optional allocations. >> >> Separate three resource type checking if we need to release >> assigned resource after requested + add_size try. >> 1. if there is io port assign fail, will release assigned io port. >> 2. if there is pref mmio assign fail, release assigned pref mmio. >> if assigned pref mmio's parent is non-pref mmio and there >> is non-pref mmio assign fail, will release that assigned pref mmio. >> 3. if there is non-pref mmio assign fail or pref mmio assigned fail, >> will release assigned non-pref mmio. >> >> This will be become more often when we have x86 8 sockets or 32 sockets >> system, and those systems will have one root bus per socket. >> They will have some root buses that do not have ioport range or 32bit mmio. >> >> -v2: need to remove assigned entries from optional list too. >> -v3: not just checking ioport related, requested by Bjorn. >> >> Reported-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> > > I forgot; is there a mailing list archive URL for this report? yes, should be http://marc.info/?l=linux-pci&m=136941328913610&w=1 title is: Resource assignment oddities > > And did you say this should go to stable for v3.10+? If that's the > case, this should probably go in my for-linus branch for v3.11 instead > of waiting for v3.12, right? Yes. You are right. BenH at last only hope it could backport to v3.10 for the distribution. 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
