[Qemu-devel] [PATCH] RDMA: Reduce restriction on block length match

["Dr. David Alan Gilbert (git)" <dgilbert@redhat.com>]

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

My e4d633207 patch has an over zealous sanity check that checked
the lengths of the RAM Blocks on source/destination were the same.  This
isn't true because of the 'used_length' trick for RAM blocks like the
ACPI table that vary in size.

Prior to that patch RDMA would also fail in this case, but it should
now work with the changes in the set e4d633207 is in.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

Fixes: e4d633207c129dc5b7d145240ac4a1997ef3902f
---
 migration/rdma.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/migration/rdma.c b/migration/rdma.c
index f106b2a..1d094b0 100644
--- a/migration/rdma.c
+++ b/migration/rdma.c
@@ -3338,14 +3338,15 @@ static int qemu_rdma_registration_stop(QEMUFile *f, void *opaque,
         for (i = 0; i < nb_dest_blocks; i++) {
             network_to_dest_block(&rdma->dest_blocks[i]);
 
-            /* We require that the blocks are in the same order */
+            /* We require that the blocks are in the same order,
+             * but the used_length trick for acpi blocks means that
+             * the destination can validly be larger than the source
+             */
             if (rdma->dest_blocks[i].length != local->block[i].length) {
-                ERROR(errp, "Block %s/%d has a different length %" PRIu64
-                            "vs %" PRIu64, local->block[i].block_name, i,
-                            local->block[i].length,
+                fprintf(stderr, "INFO: Block %s/%d has a different length %"
+                            PRIu64 "vs %" PRIu64, local->block[i].block_name,
+                            i, local->block[i].length,
                             rdma->dest_blocks[i].length);
-                rdma->error_state = -EINVAL;
-                return -EINVAL;
             }
             local->block[i].remote_host_addr =
                     rdma->dest_blocks[i].remote_host_addr;
-- 
2.4.3