diff options
authorPaolo Bonzini <pbonzini@redhat.com>2015-10-01 10:59:50 +0200
committerMarkus Armbruster <armbru@redhat.com>2015-10-09 15:25:56 +0200
commit2e2b8eb70fdb7dfbec39f3a19b20f9a73f2f813e (patch)
parentc6047e9621f77a65993bcda8f58b676996e24bb5 (diff)
memory: allow destroying a non-empty MemoryRegion
This is legal; the MemoryRegion will simply unreference all the existing subregions and possibly bring them down with it as well. However, it requires a bit of care to avoid an infinite loop. Finalizing a memory region cannot trigger an address space update, but memory_region_del_subregion errs on the side of caution and might trigger a spurious update: avoid that by resetting mr->enabled first. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1443689999-12182-2-git-send-email-armbru@redhat.com>
1 files changed, 16 insertions, 1 deletions
diff --git a/memory.c b/memory.c
index 1b03d2251c..2eb1597518 100644
--- a/memory.c
+++ b/memory.c
@@ -1304,7 +1304,22 @@ static void memory_region_finalize(Object *obj)
MemoryRegion *mr = MEMORY_REGION(obj);
- assert(QTAILQ_EMPTY(&mr->subregions));
+ assert(!mr->container);
+ /* We know the region is not visible in any address space (it
+ * does not have a container and cannot be a root either because
+ * it has no references, so we can blindly clear mr->enabled.
+ * memory_region_set_enabled instead could trigger a transaction
+ * and cause an infinite loop.
+ */
+ mr->enabled = false;
+ memory_region_transaction_begin();
+ while (!QTAILQ_EMPTY(&mr->subregions)) {
+ MemoryRegion *subregion = QTAILQ_FIRST(&mr->subregions);
+ memory_region_del_subregion(mr, subregion);
+ }
+ memory_region_transaction_commit();
g_free((char *)mr->name);