runqemu-gen-tapdevs: Add note about NetworkManager & tap devices

NetworkManager can clobber tap devices if left alone, this gives a
note about how to set tap* as unmanaged

[YOCTO #8587]

(From OE-Core rev: 503a80de1cc9097fdc8f6b5b7d0e3a3991b0ecd2)

Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/scripts/runqemu-gen-tapdevs b/scripts/runqemu-gen-tapdevs
index d3b27be291..624deacb70 100755
--- a/scripts/runqemu-gen-tapdevs
+++ b/scripts/runqemu-gen-tapdevs
@@ -85,6 +85,15 @@ for ((index=0; index < $COUNT; index++)); do
         fi
 done
 
+if [ $COUNT -gt 0 ]; then
+        echo "Note: For systems running NetworkManager, it's recommended"
+        echo "Note: that the tap devices be set as unmanaged in the"
+        echo "Note: NetworkManager.conf file. Add the following lines to"
+        echo "Note: /etc/NetworkManager/NetworkManager.conf"
+        echo "[keyfile]"
+        echo "unmanaged-devices=interface-name:tap*"
+fi
+
 # The runqemu script will check for this file, and if it exists,
 # will use the existing bank of tap devices without creating
 # additional ones via sudo.