On 31/07/2019 09:34, Jan Beulich wrote: > On 30.07.2019 19:56, Roman Shaposhnik wrote: >> On Fri, Jul 26, 2019 at 1:06 AM Jan Beulich <jbeul...@suse.com> wrote: >>> On 23.07.2019 20:25, Roman Shaposhnik wrote: >>>> Interestingly enough, adding iommu_inclusive_mapping=1 AND iommu=debug >>>> booted the system just fine. >>> Btw (I've noticed this only now) - are you saying without "iommu=debug" >>> the box does _not_ boot fine, despite the other option? >> Yes. But it made sense to me since iommu=debug (as per your >> explanation) overwhelms the CPU and I guess adding >> iommu_inclusive_mapping=1 avoids the code path that does it? > I'm afraid I don't follow: My question was whether > "iommu_inclusive_mapping=1" alone would not allow the box to boot. > Without "iommu=debug" there's no excessive logging afaict, no > matter what other IOMMU options you use.
Without inclusive mappings, the system boots but the screen is junk and there are DMA faults all over the place. With inclusive mappings, it all "works" fine. With debug enabled, the DMA faults are spat out to the console for a short while, until an APIC error occurs and the system wedges completely. ~Andrew _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
