[PATCH v6 08/20] intel_iommu: Check stage-1 translation result with interrupt range

[Zhenzhong Duan]

Per VT-d spec 4.1 section 3.15, "Untranslated requests and translation
requests that result in an address in the interrupt range will be
blocked with condition code LGN.4 or SGN.8."

This applies to both stage-1 and stage-2 IOMMU page table, move the
check from vtd_iova_to_slpte() to vtd_do_iommu_translate() so stage-1
page table could also be checked.

By this chance, update the comment with correct section number.

Suggested-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Clément Mathieu--Drif<clement.mathieu--drif@eviden.com>
Acked-by: Jason Wang <jasowang@redhat.com>
---
 hw/i386/intel_iommu.c | 48 ++++++++++++++++++++++---------------------
 1 file changed, 25 insertions(+), 23 deletions(-)

diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index a4a2a44f92..594c8e3272 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -1138,7 +1138,6 @@ static int vtd_iova_to_slpte(IntelIOMMUState *s, 
VTDContextEntry *ce,
     uint32_t offset;
     uint64_t slpte;
     uint64_t access_right_check;
-    uint64_t xlat, size;
 
     if (!vtd_iova_sl_range_check(s, iova, ce, aw_bits, pasid)) {
         error_report_once("%s: detected IOVA overflow (iova=0x%" PRIx64 ","
@@ -1191,28 +1190,7 @@ static int vtd_iova_to_slpte(IntelIOMMUState *s, 
VTDContextEntry *ce,
         level--;
     }
 
-    xlat = vtd_get_pte_addr(*slptep, aw_bits);
-    size = ~vtd_pt_level_page_mask(level) + 1;
-
-    /*
-     * From VT-d spec 3.14: Untranslated requests and translation
-     * requests that result in an address in the interrupt range will be
-     * blocked with condition code LGN.4 or SGN.8.
-     */
-    if ((xlat > VTD_INTERRUPT_ADDR_LAST ||
-         xlat + size - 1 < VTD_INTERRUPT_ADDR_FIRST)) {
-        return 0;
-    } else {
-        error_report_once("%s: xlat address is in interrupt range "
-                          "(iova=0x%" PRIx64 ", level=0x%" PRIx32 ", "
-                          "slpte=0x%" PRIx64 ", write=%d, "
-                          "xlat=0x%" PRIx64 ", size=0x%" PRIx64 ", "
-                          "pasid=0x%" PRIx32 ")",
-                          __func__, iova, level, slpte, is_write,
-                          xlat, size, pasid);
-        return s->scalable_mode ? -VTD_FR_SM_INTERRUPT_ADDR :
-                                  -VTD_FR_INTERRUPT_ADDR;
-    }
+    return 0;
 }
 
 typedef int (*vtd_page_walk_hook)(const IOMMUTLBEvent *event, void *private);
@@ -2064,6 +2042,7 @@ static bool vtd_do_iommu_translate(VTDAddressSpace 
*vtd_as, PCIBus *bus,
     uint8_t access_flags;
     bool rid2pasid = (pasid == PCI_NO_PASID) && s->root_scalable;
     VTDIOTLBEntry *iotlb_entry;
+    uint64_t xlat, size;
 
     /*
      * We have standalone memory region for interrupt addresses, we
@@ -2173,6 +2152,29 @@ static bool vtd_do_iommu_translate(VTDAddressSpace 
*vtd_as, PCIBus *bus,
         ret_fr = vtd_iova_to_slpte(s, &ce, addr, is_write, &pte, &level,
                                    &reads, &writes, s->aw_bits, pasid);
     }
+    if (!ret_fr) {
+        xlat = vtd_get_pte_addr(pte, s->aw_bits);
+        size = ~vtd_pt_level_page_mask(level) + 1;
+
+        /*
+         * Per VT-d spec 4.1 section 3.15: Untranslated requests and 
translation
+         * requests that result in an address in the interrupt range will be
+         * blocked with condition code LGN.4 or SGN.8.
+         */
+        if ((xlat <= VTD_INTERRUPT_ADDR_LAST &&
+             xlat + size - 1 >= VTD_INTERRUPT_ADDR_FIRST)) {
+            error_report_once("%s: xlat address is in interrupt range "
+                              "(iova=0x%" PRIx64 ", level=0x%" PRIx32 ", "
+                              "pte=0x%" PRIx64 ", write=%d, "
+                              "xlat=0x%" PRIx64 ", size=0x%" PRIx64 ", "
+                              "pasid=0x%" PRIx32 ")",
+                              __func__, addr, level, pte, is_write,
+                              xlat, size, pasid);
+            ret_fr = s->scalable_mode ? -VTD_FR_SM_INTERRUPT_ADDR :
+                                        -VTD_FR_INTERRUPT_ADDR;
+        }
+    }
+
     if (ret_fr) {
         vtd_report_fault(s, -ret_fr, is_fpd_set, source_id,
                          addr, is_write, pasid != PCI_NO_PASID, pasid);
-- 
2.34.1