Commit 2e2b8eb7 authored by Paolo Bonzini's avatar Paolo Bonzini Committed by Markus Armbruster
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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: default avatarPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
Message-Id: <1443689999-12182-2-git-send-email-armbru@redhat.com>
parent c6047e96

memory.c

+16 −1
Original line number Diff line number Diff line
@@ -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();



    mr->destructor(mr);

    memory_region_clear_coalescing(mr);

    g_free((char *)mr->name);