Index: head/sys/kern/uipc_sockbuf.c
===================================================================
--- head/sys/kern/uipc_sockbuf.c
+++ head/sys/kern/uipc_sockbuf.c
@@ -112,7 +112,42 @@
 
 	for (m = m0; m != end; m = m->m_next) {
 		MPASS((m->m_flags & M_NOTREADY) == 0);
+		/*
+		 * NB: In sbcompress(), 'n' is the last mbuf in the
+		 * socket buffer and 'm' is the new mbuf being copied
+		 * into the trailing space of 'n'.  Here, the roles
+		 * are reversed and 'n' is the next mbuf after 'm'
+		 * that is being copied into the trailing space of
+		 * 'm'.
+		 */
+		n = m->m_next;
+#ifdef KERN_TLS
+		/* Try to coalesce adjacent ktls mbuf hdr/trailers. */
+		if ((n != NULL) && (n != end) && (m->m_flags & M_EOR) == 0 &&
+		    (m->m_flags & M_NOMAP) &&
+		    (n->m_flags & M_NOMAP) &&
+		    !mbuf_has_tls_session(m) &&
+		    !mbuf_has_tls_session(n)) {
+			struct mbuf_ext_pgs *mpgs, *npgs;
+			int hdr_len, trail_len;
 
+			mpgs = m->m_ext.ext_pgs;
+			npgs = n->m_ext.ext_pgs;
+			hdr_len = npgs->hdr_len;
+			trail_len = mpgs->trail_len;
+			if (trail_len != 0 && hdr_len != 0 &&
+			    trail_len + hdr_len <= MBUF_PEXT_TRAIL_LEN) {
+				/* copy n's header to m's trailer */
+				memcpy(&mpgs->trail[trail_len], npgs->hdr,
+				    hdr_len);
+				mpgs->trail_len += hdr_len;
+				m->m_len += hdr_len;
+				npgs->hdr_len = 0;
+				n->m_len -= hdr_len;
+			}
+		}
+#endif
+
 		/* Compress small unmapped mbufs into plain mbufs. */
 		if ((m->m_flags & M_NOMAP) && m->m_len <= MLEN &&
 		    !mbuf_has_tls_session(m)) {
@@ -124,15 +159,6 @@
 			}
 		}
 
-		/*
-		 * NB: In sbcompress(), 'n' is the last mbuf in the
-		 * socket buffer and 'm' is the new mbuf being copied
-		 * into the trailing space of 'n'.  Here, the roles
-		 * are reversed and 'n' is the next mbuf after 'm'
-		 * that is being copied into the trailing space of
-		 * 'm'.
-		 */
-		n = m->m_next;
 		while ((n != NULL) && (n != end) && (m->m_flags & M_EOR) == 0 &&
 		    M_WRITABLE(m) &&
 		    (m->m_flags & M_NOMAP) == 0 &&