msi: Guard msi/msix_write_config with msi_present

Terminate msi/msix_write_config early if support is not enabled. This
allows to remove checks at the caller site if MSI is optional.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/hw/msi.c b/hw/msi.c
index b2903fc93c..da12f33728 100644
--- a/hw/msi.c
+++ b/hw/msi.c
@@ -276,7 +276,8 @@ void msi_write_config(PCIDevice *dev, uint32_t addr, uint32_t val, int len)
     unsigned int vector;
     uint32_t pending;
 
-    if (!ranges_overlap(addr, len, dev->msi_cap, msi_cap_sizeof(flags))) {
+    if (!msi_present(dev) ||
+        !ranges_overlap(addr, len, dev->msi_cap, msi_cap_sizeof(flags))) {
         return;
     }