9 files changed, 31 insertions, 5 deletions

diff --git a/hw/core/loader.c b/hw/core/loader.c
index d56963699b..44311ff43d 100644
--- a/hw/core/loader.c
+++ b/hw/core/loader.c
@@ -727,6 +727,7 @@ int rom_load_all(void)
         addr += rom->romsize;
         section = memory_region_find(get_system_memory(), rom->addr, 1);
         rom->isrom = int128_nz(section.size) && memory_region_is_rom(section.mr);
+        memory_region_unref(section.mr);
     }
     qemu_register_reset(rom_reset, NULL);
     roms_loaded = 1;
diff --git a/hw/display/exynos4210_fimd.c b/hw/display/exynos4210_fimd.c
index d9088d9594..b520f524f7 100644
--- a/hw/display/exynos4210_fimd.c
+++ b/hw/display/exynos4210_fimd.c
@@ -1126,6 +1126,11 @@ static void fimd_update_memory_section(Exynos4210fimdState *s, unsigned win)
     /* Total number of bytes of virtual screen used by current window */
     w->fb_len = fb_mapped_len = (w->virtpage_width + w->virtpage_offsize) *
             (w->rightbot_y - w->lefttop_y + 1);
+
+    /* TODO: add .exit and unref the region there.  Not needed yet since sysbus
+     * does not support hot-unplug.
+     */
+    memory_region_unref(w->mem_section.mr);
     w->mem_section = memory_region_find(sysbus_address_space(&s->busdev),
             fb_start_addr, w->fb_len);
     assert(w->mem_section.mr);
@@ -1154,6 +1159,7 @@ static void fimd_update_memory_section(Exynos4210fimdState *s, unsigned win)
     return;
 
 error_return:
+    memory_region_unref(w->mem_section.mr);
     w->mem_section.mr = NULL;
     w->mem_section.size = int128_zero();
     w->host_fb_addr = NULL;
diff --git a/hw/display/framebuffer.c b/hw/display/framebuffer.c
index 49c9e59043..4546e42654 100644
--- a/hw/display/framebuffer.c
+++ b/hw/display/framebuffer.c
@@ -54,11 +54,11 @@ void framebuffer_update_display(
     src_len = src_width * rows;
 
     mem_section = memory_region_find(address_space, base, src_len);
+    mem = mem_section.mr;
     if (int128_get64(mem_section.size) != src_len ||
             !memory_region_is_ram(mem_section.mr)) {
-        return;
+        goto out;
     }
-    mem = mem_section.mr;
     assert(mem);
     assert(mem_section.offset_within_address_space == base);
 
@@ -68,10 +68,10 @@ void framebuffer_update_display(
        but it's not really worth it as dirty flag tracking will probably
        already have failed above.  */
     if (!src_base)
-        return;
+        goto out;
     if (src_len != src_width * rows) {
         cpu_physical_memory_unmap(src_base, src_len, 0, 0);
-        return;
+        goto out;
     }
     src = src_base;
     dest = surface_data(ds);
@@ -102,10 +102,12 @@ void framebuffer_update_display(
     }
     cpu_physical_memory_unmap(src_base, src_len, 0, 0);
     if (first < 0) {
-        return;
+        goto out;
     }
     memory_region_reset_dirty(mem, mem_section.offset_within_region, src_len,
                               DIRTY_MEMORY_VGA);
     *first_row = first;
     *last_row = last;
+out:
+    memory_region_unref(mem);
 }
diff --git a/hw/i386/kvmvapic.c b/hw/i386/kvmvapic.c
index 08da69e4d1..21b59122dd 100644
--- a/hw/i386/kvmvapic.c
+++ b/hw/i386/kvmvapic.c
@@ -605,6 +605,7 @@ static void vapic_map_rom_writable(VAPICROMState *s)
                              rom_size);
     memory_region_add_subregion_overlap(as, rom_paddr, &s->rom, 1000);
     s->rom_mapped_writable = true;
+    memory_region_unref(section.mr);
 }
 
 static int vapic_prepare(VAPICROMState *s)
diff --git a/hw/misc/vfio.c b/hw/misc/vfio.c
index e2e957d6f6..675bbfc97a 100644
--- a/hw/misc/vfio.c
+++ b/hw/misc/vfio.c
@@ -1969,6 +1969,7 @@ static void vfio_listener_region_add(MemoryListener *listener,
     DPRINTF("region_add %"HWADDR_PRIx" - %"HWADDR_PRIx" [%p]\n",
             iova, end - 1, vaddr);
 
+    memory_region_ref(section->mr);
     ret = vfio_dma_map(container, iova, end - iova, vaddr, section->readonly);
     if (ret) {
         error_report("vfio_dma_map(%p, 0x%"HWADDR_PRIx", "
@@ -2010,6 +2011,7 @@ static void vfio_listener_region_del(MemoryListener *listener,
             iova, end - 1);
 
     ret = vfio_dma_unmap(container, iova, end - iova);
+    memory_region_unref(section->mr);
     if (ret) {
         error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", "
                      "0x%"HWADDR_PRIx") = %d (%m)",
diff --git a/hw/virtio/dataplane/hostmem.c b/hw/virtio/dataplane/hostmem.c
index 7e46723eb1..901d98b8a0 100644
--- a/hw/virtio/dataplane/hostmem.c
+++ b/hw/virtio/dataplane/hostmem.c
@@ -64,8 +64,12 @@ out:
 static void hostmem_listener_commit(MemoryListener *listener)
 {
     HostMem *hostmem = container_of(listener, HostMem, listener);
+    int i;
 
     qemu_mutex_lock(&hostmem->current_regions_lock);
+    for (i = 0; i < hostmem->num_current_regions; i++) {
+        memory_region_unref(hostmem->current_regions[i].mr);
+    }
     g_free(hostmem->current_regions);
     hostmem->current_regions = hostmem->new_regions;
     hostmem->num_current_regions = hostmem->num_new_regions;
@@ -92,8 +96,11 @@ static void hostmem_append_new_region(HostMem *hostmem,
         .guest_addr = section->offset_within_address_space,
         .size = int128_get64(section->size),
         .readonly = section->readonly,
+        .mr = section->mr,
     };
     hostmem->num_new_regions++;
+
+    memory_region_ref(section->mr);
 }
 
 static void hostmem_listener_append_region(MemoryListener *listener,
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index baf84ea0bd..96ab62517a 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -497,6 +497,7 @@ static void vhost_region_add(MemoryListener *listener,
     dev->mem_sections = g_renew(MemoryRegionSection, dev->mem_sections,
                                 dev->n_mem_sections);
     dev->mem_sections[dev->n_mem_sections - 1] = *section;
+    memory_region_ref(section->mr);
     vhost_set_memory(listener, section, true);
 }
 
@@ -512,6 +513,7 @@ static void vhost_region_del(MemoryListener *listener,
     }
 
     vhost_set_memory(listener, section, false);
+    memory_region_unref(section->mr);
     for (i = 0; i < dev->n_mem_sections; ++i) {
         if (dev->mem_sections[i].offset_within_address_space
             == section->offset_within_address_space) {
diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
index a27051c2e7..3fa72a97b9 100644
--- a/hw/virtio/virtio-balloon.c
+++ b/hw/virtio/virtio-balloon.c
@@ -205,6 +205,7 @@ static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq)
             addr = section.offset_within_region;
             balloon_page(memory_region_get_ram_ptr(section.mr) + addr,
                          !!(vq == s->dvq));
+            memory_region_unref(section.mr);
         }
 
         virtqueue_push(vq, &elem, offset);
diff --git a/hw/xen/xen_pt.c b/hw/xen/xen_pt.c
index 15b489620b..c06a01821d 100644
--- a/hw/xen/xen_pt.c
+++ b/hw/xen/xen_pt.c
@@ -606,6 +606,7 @@ static void xen_pt_region_add(MemoryListener *l, MemoryRegionSection *sec)
     XenPCIPassthroughState *s = container_of(l, XenPCIPassthroughState,
                                              memory_listener);
 
+    memory_region_ref(sec->mr);
     xen_pt_region_update(s, sec, true);
 }
 
@@ -615,6 +616,7 @@ static void xen_pt_region_del(MemoryListener *l, MemoryRegionSection *sec)
                                              memory_listener);
 
     xen_pt_region_update(s, sec, false);
+    memory_region_unref(sec->mr);
 }
 
 static void xen_pt_io_region_add(MemoryListener *l, MemoryRegionSection *sec)
@@ -622,6 +624,7 @@ static void xen_pt_io_region_add(MemoryListener *l, MemoryRegionSection *sec)
     XenPCIPassthroughState *s = container_of(l, XenPCIPassthroughState,
                                              io_listener);
 
+    memory_region_ref(sec->mr);
     xen_pt_region_update(s, sec, true);
 }
 
@@ -631,6 +634,7 @@ static void xen_pt_io_region_del(MemoryListener *l, MemoryRegionSection *sec)
                                              io_listener);
 
     xen_pt_region_update(s, sec, false);
+    memory_region_unref(sec->mr);
 }
 
 static const MemoryListener xen_pt_memory_listener = {