x86: Filter out physical address that can't be handled by DMAR units

Make sure that we do not try to program DMAR page tables with physical
addresses beyond the supported range (39 or 48 bits, depending on the
page table levels).

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>

diff --git a/hypervisor/arch/x86/vtd.c b/hypervisor/arch/x86/vtd.c
index 28faf51a374831cd6ed7863a46b9ccfa24c5875e..6d36394c8196dd188cb3cc9469565579aa0d24fb 100644 (file)
--- a/hypervisor/arch/x86/vtd.c
+++ b/hypervisor/arch/x86/vtd.c
@@ -773,6 +773,9 @@ int iommu_map_memory_region(struct cell *cell,
        if (!(mem->flags & JAILHOUSE_MEM_DMA))
                return 0;
 
+       if (mem->virt_start & BIT_MASK(63, 12 + 9 * dmar_pt_levels))
+               return trace_error(-E2BIG);
+
        if (mem->flags & JAILHOUSE_MEM_READ)
                flags |= VTD_PAGE_READ;
        if (mem->flags & JAILHOUSE_MEM_WRITE)