PCI spec says:

For all accesses to MSI-X Table and MSI-X PBA fields, software must use
aligned full DWORD or aligned full QWORD transactions; otherwise, the
result is undefined.

However, since MSI-X was converted to use memory API, QEMU
started blocking qword transactions, only allowing DWORD
ones. Guests do not seem to use QWORD accesses, but let's
be spec compliant.

Fixes: 95524ae8dc8f ("msix: convert to memory API")
Signed-off-by: Michael S. Tsirkin <m...@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <phi...@redhat.com>
---
 hw/pci/msix.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/hw/pci/msix.c b/hw/pci/msix.c
index 29187898f2..e6a5559038 100644
--- a/hw/pci/msix.c
+++ b/hw/pci/msix.c
@@ -199,6 +199,9 @@ static const MemoryRegionOps msix_table_mmio_ops = {
     .endianness = DEVICE_LITTLE_ENDIAN,
     .valid = {
         .min_access_size = 4,
+        .max_access_size = 8,
+    },
+    .impl = {
         .max_access_size = 4,
     },
 };
@@ -227,6 +230,9 @@ static const MemoryRegionOps msix_pba_mmio_ops = {
     .endianness = DEVICE_LITTLE_ENDIAN,
     .valid = {
         .min_access_size = 4,
+        .max_access_size = 8,
+    },
+    .impl = {
         .max_access_size = 4,
     },
 };
-- 
MST


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