diff --git a/cmn/objlist_utils.go b/cmn/objlist_utils.go
index 44aec9867db..80dcb2256e5 100644
--- a/cmn/objlist_utils.go
+++ b/cmn/objlist_utils.go
@@ -225,12 +225,14 @@ func TokenGreaterEQ(token, objName string) bool { return token >= objName }
 // an alternative name for this function could be smth. like SameBranch()
 // see also: cos.TrimPrefix
 func DirHasOrIsPrefix(dirPath, prefix string) bool {
-	return prefix == "" || (strings.HasPrefix(prefix, dirPath) || strings.HasPrefix(dirPath, prefix))
+	debug.Assert(prefix != "")
+	return strings.HasPrefix(prefix, dirPath) || strings.HasPrefix(dirPath, prefix)
 }
 
 // see also: cos.TrimPrefix
 func ObjHasPrefix(objName, prefix string) bool {
-	return prefix == "" || strings.HasPrefix(objName, prefix)
+	debug.Assert(prefix != "")
+	return strings.HasPrefix(objName, prefix)
 }
 
 // no recursion (LsNoRecursion) helper function:
diff --git a/reb/globrun.go b/reb/globrun.go
index c262a12b0a8..9de6ec8eb5c 100644
--- a/reb/globrun.go
+++ b/reb/globrun.go
@@ -10,6 +10,7 @@ import (
 	"io"
 	"net/http"
 	"path/filepath"
+	"strings"
 	"sync"
 	ratomic "sync/atomic"
 	"time"
@@ -834,8 +835,14 @@ func (rj *rebJogger) _lwalk(lom *core.LOM, fqn string) error {
 	if rj.rargs.prefix != "" {
 		debug.Assert(rj.rargs.bck != nil)
 		if !cmn.ObjHasPrefix(lom.ObjName, rj.rargs.prefix) {
-			if len(lom.ObjName) > len(rj.rargs.prefix)+1 {
-				nlog.Warningln(rj.rargs.logHdr, "skip-dir", lom.ObjName)
+			//
+			// TODO: unify via (fs.WalkBck => validateCb => cmn.DirHasOrIsPrefix)
+			//
+			i := strings.IndexByte(lom.ObjName, filepath.Separator)
+			if i > 0 && !cmn.DirHasOrIsPrefix(lom.ObjName[:i], rj.rargs.prefix) {
+				if cmn.Rom.FastV(4, cos.SmoduleReb) {
+					nlog.Warningln(rj.rargs.logHdr, "skip-dir", lom.ObjName, "prefix", rj.rargs.prefix)
+				}
 				return filepath.SkipDir
 			}
 			return cmn.ErrSkip
diff --git a/xact/xs/wi_lso.go b/xact/xs/wi_lso.go
index decaebbaba6..50031c3d2d4 100644
--- a/xact/xs/wi_lso.go
+++ b/xact/xs/wi_lso.go
@@ -66,7 +66,7 @@ func (wi *walkInfo) processDir(fqn string) error {
 		return nil
 	}
 
-	if !cmn.DirHasOrIsPrefix(ct.ObjectName(), wi.msg.Prefix) {
+	if wi.msg.Prefix != "" && !cmn.DirHasOrIsPrefix(ct.ObjectName(), wi.msg.Prefix) {
 		return filepath.SkipDir
 	}
 
@@ -81,7 +81,7 @@ func (wi *walkInfo) processDir(fqn string) error {
 }
 
 func (wi *walkInfo) match(objName string) bool {
-	if !cmn.ObjHasPrefix(objName, wi.msg.Prefix) {
+	if wi.msg.Prefix != "" && !cmn.ObjHasPrefix(objName, wi.msg.Prefix) {
 		return false
 	}
 	return wi.msg.ContinuationToken == "" || !cmn.TokenGreaterEQ(wi.msg.ContinuationToken, objName)