commit b1ab8f9cc554e3c92200d44ce9d65bab50be183e
author Peter Maydell <peter.maydell@linaro.org> Tue Apr 04 16:37:31 2023 -0400
committer Peter Maydell <peter.maydell@linaro.org> Wed Apr 05 13:31:52 2023 +0100
tree 160b86f1123d6dbad43ee9a1a3950969226a3aeb
parent b5fba99ec7969054ab2f3727d2df014b5b72e4f1

Revert "memory: Optimize replay of guest mapping"

This reverts commit 6da24341866fa940fd7d575788a2319514941c77
("memory: Optimize replay of guest mapping").

This change breaks the mps3-an547 board under TCG (and
probably other TCG boards using an IOMMU), which now
assert:

$ ./build/x86/qemu-system-arm --machine mps3-an547 -serial stdio
-kernel /tmp/an547-mwe/build/test.elf
qemu-system-arm: ../../softmmu/memory.c:1903:
memory_region_register_iommu_notifier: Assertion `n->end <=
memory_region_size(mr)' failed.

This is because tcg_register_iommu_notifier() registers
an IOMMU notifier which covers the entire address space,
so the assertion added in this commit is not correct.

For the 8.0 release, just revert this commit as it is
only an optimization.

Fixes: 6da24341866f ("memory: Optimize replay of guest mapping")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 917c1c552b2d1b732f9a86c6a90684c3a5e4cada.1680640587.git.mst@redhat.com

hw/i386/intel_iommu.c

diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index faade7d..a628967 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -3850,7 +3850,7 @@
                 .domain_id = vtd_get_domain_id(s, &ce, vtd_as->pasid),
             };
 
-            vtd_page_walk(s, &ce, n->start, n->end, &info, vtd_as->pasid);
+            vtd_page_walk(s, &ce, 0, ~0ULL, &info, vtd_as->pasid);
         }
     } else {
         trace_vtd_replay_ce_invalid(bus_n, PCI_SLOT(vtd_as->devfn),

softmmu/memory.c

diff --git a/softmmu/memory.c b/softmmu/memory.c
index 5305aca..b1a6cae 100644
--- a/softmmu/memory.c
+++ b/softmmu/memory.c
@@ -1900,7 +1900,6 @@
     iommu_mr = IOMMU_MEMORY_REGION(mr);
     assert(n->notifier_flags != IOMMU_NOTIFIER_NONE);
     assert(n->start <= n->end);
-    assert(n->end <= memory_region_size(mr));
     assert(n->iommu_idx >= 0 &&
            n->iommu_idx < memory_region_iommu_num_indexes(iommu_mr));
 
@@ -1924,6 +1923,7 @@
 
 void memory_region_iommu_replay(IOMMUMemoryRegion *iommu_mr, IOMMUNotifier *n)
 {
+    MemoryRegion *mr = MEMORY_REGION(iommu_mr);
     IOMMUMemoryRegionClass *imrc = IOMMU_MEMORY_REGION_GET_CLASS(iommu_mr);
     hwaddr addr, granularity;
     IOMMUTLBEntry iotlb;
@@ -1936,7 +1936,7 @@
 
     granularity = memory_region_iommu_get_min_page_size(iommu_mr);
 
-    for (addr = n->start; addr < n->end; addr += granularity) {
+    for (addr = 0; addr < memory_region_size(mr); addr += granularity) {
         iotlb = imrc->translate(iommu_mr, addr, IOMMU_NONE, n->iommu_idx);
         if (iotlb.perm != IOMMU_NONE) {
             n->notify(n, &iotlb);