On Thu, Jun 8, 2023 at 11:02 AM Robin Murphy <robin.murphy@xxxxxxx> wrote: > > On 2023-06-08 18:10, Alexander Duyck wrote: <...> > > As a part of going down that rabbit hole I realized that the > > reserved_regions seems to only list the MSI reservation. However after > > digging a bit deeper it seems like there is code to reserve the memory > > behind the root complex in the IOVA but it doesn't look like that is > > visible anywhere and is the piece I am currently trying to sort out. > > What I am working on is trying to figure out if the system that is > > failing is actually reserving that memory region in the IOVA, or if > > that is somehow not happening in our test setup. > > How old's the kernel? Before 5.11, intel-iommu wasn't hooked up to > iommu-dma so didn't do quite the same thing - it only reserved whatever > specific PCI memory resources existed at boot, rather than the whole > window as iommu-dma does. Either way, ftrace on reserve_iova() (or just > whack a print in there) should suffice to see what's happened. > > Robin. We are working with a 5.12 kernel. I will do some digging. We may be able to backport some fixes if needed. Thanks, - Alex
