[PATCH 1/4] um: virtio_uml: send SET_MEM_TABLE message with the exact size

[Benjamin Berg <benjamin@sipsolutions.net>]

From: Benjamin Berg <benjamin.berg@intel.com>

The rust based userspace vhost devices are very strict and will not
accept the message if it is longer than required. So, only include the
data for the first memory region.

Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
---
 arch/um/drivers/virtio_uml.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/um/drivers/virtio_uml.c b/arch/um/drivers/virtio_uml.c
index 4d3e9b9f5b61..c602892f329f 100644
--- a/arch/um/drivers/virtio_uml.c
+++ b/arch/um/drivers/virtio_uml.c
@@ -623,7 +623,7 @@ static int vhost_user_set_mem_table(struct virtio_uml_device *vu_dev)
 {
 	struct vhost_user_msg msg = {
 		.header.request = VHOST_USER_SET_MEM_TABLE,
-		.header.size = sizeof(msg.payload.mem_regions),
+		.header.size = offsetof(typeof(msg.payload.mem_regions), regions[1]),
 		.payload.mem_regions.num = 1,
 	};
 	unsigned long reserved = uml_reserved - uml_physmem;
-- 
2.47.0