It is no need to dirty-track MMIO regions or other readonly regions.

Before we start or stop to dirty-track a memory region, check the type of
the memory region. The region must be a writeable ram to be dirty-tracked.

Signed-off-by: Yan-Jie Wang <ubzeme@gmail.com>
---
 accel/hvf/hvf-mem.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/accel/hvf/hvf-mem.c b/accel/hvf/hvf-mem.c
index 2f70ceb307..b215386bc8 100644
--- a/accel/hvf/hvf-mem.c
+++ b/accel/hvf/hvf-mem.c
@@ -180,6 +180,11 @@ static void hvf_set_dirty_tracking(MemoryRegionSection *section, bool on)
 {
     HVFSlot *slot;
 
+    if (!memory_region_is_ram(section->mr) || memory_region_is_rom(section)) {
+        /* do not consider memory regions which are not directly writeable */
+        return;
+    }
+
     qemu_mutex_lock(&memlock);
 
     slot = hvf_find_overlap_slot(
-- 
2.32.0 (Apple Git-132)