dm: report which conflicting type caused error during table_load()

Eases troubleshooting to know the before vs after types.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>

diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 5acf77d..b810ea7 100644 (file)
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -1344,7 +1344,8 @@ static int table_load(struct file *filp, struct dm_ioctl *param, size_t param_si
                        goto err_unlock_md_type;
                }
        } else if (!is_valid_type(dm_get_md_type(md), dm_table_get_type(t))) {
-               DMWARN("can't change device type after initial table load.");
+               DMWARN("can't change device type (old=%u vs new=%u) after initial table load.",
+                      dm_get_md_type(md), dm_table_get_type(t));
                r = -EINVAL;
                goto err_unlock_md_type;
        }