On 23.09.2019 18:30, Paul Durrant wrote: >> -----Original Message----- >> From: Xen-devel <xen-devel-boun...@lists.xenproject.org> On Behalf Of Jan >> Beulich >> Sent: 19 September 2019 14:25 >> To: xen-devel@lists.xenproject.org >> Cc: Andrew Cooper <andrew.coop...@citrix.com>; Suravee Suthikulpanit >> <suravee.suthikulpa...@amd.com> >> Subject: [Xen-devel] [PATCH v6 7/8] AMD/IOMMU: allocate one device table per >> PCI segment >> >> Having a single device table for all segments can't possibly be right. > > The copy of the spec. I have says (on page 253: Fixed-Length IVHD > Blocks) that IVHD entries must have a segment group of 0, so can't > the code just require iommu->seg == 0?
The wording in my version is "At this time, only PCI Segment Group 0 is supported." This suggests to me that it is not a good idea to have logic baked in that depends on this remaining true. I realize though that there are more places than just this one where we (have to) assume segment 0 (all in iommu_acpi.c, and all marked with an XXX comment). Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
