From 48fe2389e08e8badd5232392e7e1195c96dbdb19 Mon Sep 17 00:00:00 2001
From: Kroese <kroese@users.noreply.github.com>
Date: Thu, 9 Oct 2025 11:47:32 +0200
Subject: [PATCH 1/2] feat: Make Passt MTU configurable

---
 src/network.sh | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/network.sh b/src/network.sh
index 29e78229..17e32413 100644
--- a/src/network.sh
+++ b/src/network.sh
@@ -20,6 +20,7 @@ set -Eeuo pipefail
 : "${VM_NET_MASK:="255.255.255.0"}"
 
 : "${PASST:="passt"}"
+: "${PASST_MTU:=""}"
 : "${PASST_OPTS:=""}"
 : "${PASST_DEBUG:=""}"
 
@@ -337,6 +338,7 @@ configurePasst() {
   PASST_OPTS+=" -a $ip"
   PASST_OPTS+=" -g $gateway"
   PASST_OPTS+=" -n $VM_NET_MASK"
+  [ -n "$PASST_MTU" ] && PASST_OPTS+=" -m $PASST_MTU"
 
   exclude=$(getHostPorts "$HOST_PORTS")
 
@@ -797,10 +799,9 @@ else
   esac
 
   if [[ "${NETWORK,,}" == "user"* ]]; then
-    if [[ "${ADAPTER,,}" != "rtl8139" ]]; then
-      NETWORK="passt"
-    else
-      NETWORK="slirp"
+    NETWORK="passt"
+    if [[ "${ADAPTER,,}" == "rtl8139" ]]; then
+      PASST_MTU="$MTU"
     fi
   fi
 

From fbd61aaed1731050c83bba6fca1e456ae05710f2 Mon Sep 17 00:00:00 2001
From: Kroese <kroese@users.noreply.github.com>
Date: Thu, 9 Oct 2025 12:48:56 +0200
Subject: [PATCH 2/2] Update network.sh

---
 src/network.sh | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/src/network.sh b/src/network.sh
index 17e32413..eedace38 100644
--- a/src/network.sh
+++ b/src/network.sh
@@ -338,6 +338,8 @@ configurePasst() {
   PASST_OPTS+=" -a $ip"
   PASST_OPTS+=" -g $gateway"
   PASST_OPTS+=" -n $VM_NET_MASK"
+
+  [[ "${ADAPTER,,}" == "rtl8139" ]] && [ -z "$PASST_MTU" ] && PASST_MTU="$MTU"  
   [ -n "$PASST_MTU" ] && PASST_OPTS+=" -m $PASST_MTU"
 
   exclude=$(getHostPorts "$HOST_PORTS")
@@ -423,7 +425,7 @@ configureNAT() {
   else
     ip="172.31.$base"
   fi
-  
+
   [ -n "$VM_NET_IP" ] && ip="$VM_NET_IP"
 
   local gateway=""
@@ -567,7 +569,7 @@ closeWeb() {
 closeNetwork() {
 
   if [[ "${WEB:-}" != [Nn]* ]]; then
-    closeWeb  
+    closeWeb
   fi
 
   [[ "$NETWORK" == [Nn]* ]] && return 0
@@ -799,9 +801,10 @@ else
   esac
 
   if [[ "${NETWORK,,}" == "user"* ]]; then
-    NETWORK="passt"
-    if [[ "${ADAPTER,,}" == "rtl8139" ]]; then
-      PASST_MTU="$MTU"
+    if [[ "${ADAPTER,,}" != "rtl8139" ]]; then
+      NETWORK="passt"
+    else
+      NETWORK="slirp"
     fi
   fi