Fault handling is getting enabled after enabling the interrupt-remapping (as the success of interrupt-remapping can affect the apic mode and hence the fault handling mode). Hence there can potentially be some faults between the window of enabling interrupt-remapping in the vt-d and the fault-handling of the vt-d units. Handle any previous faults after enabling the vt-d fault handling. For v2.6.38 cleanup, need to check if we can remove the dmar_fault() in the enable_intr_remapping() and see if we can enable fault handling along with enabling intr-remapping. Signed-off-by: Suresh Siddha Cc: stable@kernel.org [v2.6.32+] --- drivers/pci/dmar.c | 5 +++++ 1 file changed, 5 insertions(+) Index: tip/drivers/pci/dmar.c =================================================================== --- tip.orig/drivers/pci/dmar.c +++ tip/drivers/pci/dmar.c @@ -1417,6 +1417,11 @@ int __init enable_drhd_fault_handling(vo (unsigned long long)drhd->reg_base_addr, ret); return -1; } + + /* + * Clear any previous faults. + */ + dmar_fault(iommu->irq, iommu); } return 0;