Warn if secure data flag requested but not supported by kernel.

diff --git a/libdm/ioctl/libdm-iface.c b/libdm/ioctl/libdm-iface.c
index 9ff8b36eb44f6fa268c63a7d22a07c7c5c954eff..a8bbbccbe675265bb084b36bc3f83fb3e2833a13 100644 (file)
--- a/libdm/ioctl/libdm-iface.c
+++ b/libdm/ioctl/libdm-iface.c
@@ -1541,8 +1541,12 @@ static struct dm_ioctl *_flatten(struct dm_task *dmt, unsigned repeat_count)
                dmi->flags |= DM_READONLY_FLAG;
        if (dmt->skip_lockfs)
                dmi->flags |= DM_SKIP_LOCKFS_FLAG;
-       if (dmt->secure_data)
+       if (dmt->secure_data) {
+               if (_dm_version_minor < 20)
+                       log_warn("WARNING: Secure data flag unsupported by "
+                                "kernel.  Buffers will not be wiped after use.");
                dmi->flags |= DM_SECURE_DATA_FLAG;
+       }
        if (dmt->query_inactive_table) {
                if (_dm_version_minor < 16)
                        log_warn("WARNING: Inactive table query unsupported "