Description of problem: When using the upstream (current net-next-2.6) ixgbe driver and the latest driver proposed for RHEL5.5 we see failures reported by the iommu when receiving data: # netperf -H 11.0.0.2 -t TCP_MAERTS TCP MAERTS TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 11.0.0.2 (11.0.0.2) port 0 AF_INET DRHD: handling fault status reg 402 DMAR:[DMA Write] Request device [04:00.0] fault addr ffe43000 DMAR:[fault reason 05] PTE Write access is not set DRHD: handling fault status reg 502 DMAR:[DMA Write] Request device [04:00.0] fault addr fff62000 DMAR:[fault reason 05] PTE Write access is not set DRHD: handling fault status reg 602 DMAR:[DMA Write] Request device [04:00.0] fault addr ffcf4000 DMAR:[fault reason 05] PTE Write access is not set DRHD: handling fault status reg 702 ....
this was a known RSC issue fixed upstream via commit(s) 1) 43634e820e393ba48bb2efc3d330dee4203e80d8 2) fd3686a842717b890fbe3024b83a616c54d5dba0 3) e8171aaad7ec335b8cbd71f56eb08b545f0c404f
We have #1 in RHEL5.5 and will add the other two in RHEL5.6 as they are not really that critical. I'm going to close this as a dup of bug 568153. *** This bug has been marked as a duplicate of bug 568153 ***