[Qemu-devel] [PATCH v3 8/8] qemu_ram_resize: document assumptions

["Michael S. Tsirkin" <mst@redhat.com>]

Document that when using qemu_ram_resize for anything mapped into guest
address space, it's the job of the resize function to update guest
visible state.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 exec.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/exec.c b/exec.c
index 71af138..58ac6d6 100644
--- a/exec.c
+++ b/exec.c
@@ -1301,6 +1301,13 @@ static int memory_try_enable_merging(void *addr, size_t len)
     return qemu_madvise(addr, len, QEMU_MADV_MERGEABLE);
 }
 
+/* Only legal before guest might have detected the memory size: e.g. on
+ * incoming migration, or right after reset.
+ *
+ * As memory core doesn't know how is memory accessed, it is up to
+ * resize callback to update device state and/or add assertions to detect
+ * misuse, if necessary.
+ */
 int qemu_ram_resize(ram_addr_t base, ram_addr_t newsize, Error **errp)
 {
     RAMBlock *block = find_ram_block(base);
-- 
MST