From: Prasad J Pandit <pjp@fedoraproject.org>

Add pci-intack mmio write method to avoid NULL pointer dereference
issue.

Reported-by: Lei Sun <slei.casper@gmail.com>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
---
 hw/pci-host/prep.c | 8 ++++++++
 1 file changed, 8 insertions(+)

Update v4: add Reviewed-by tag
  -> https://lists.nongnu.org/archive/html/qemu-devel/2020-07/msg05325.html

diff --git a/hw/pci-host/prep.c b/hw/pci-host/prep.c
index 4b93fd2b01..64b33af6c0 100644
--- a/hw/pci-host/prep.c
+++ b/hw/pci-host/prep.c
@@ -26,6 +26,7 @@
 #include "qemu/osdep.h"
 #include "qemu-common.h"
 #include "qemu/units.h"
+#include "qemu/log.h"
 #include "qapi/error.h"
 #include "hw/pci/pci.h"
 #include "hw/pci/pci_bus.h"
@@ -119,8 +120,15 @@ static uint64_t raven_intack_read(void *opaque, hwaddr addr,
     return pic_read_irq(isa_pic);
 }
 
+static void raven_intack_write(void *opaque, hwaddr addr,
+                                        uint64_t data, unsigned size)
+{
+    qemu_log_mask(LOG_UNIMP, "%s not implemented\n", __func__);
+}
+
 static const MemoryRegionOps raven_intack_ops = {
     .read = raven_intack_read,
+    .write = raven_intack_write,
     .valid = {
         .max_access_size = 1,
     },
-- 
2.26.2