miragesdk: do not die brutally when the calf terminates

Signed-off-by: Thomas Gazagnaire <thomas@gazagnaire.org>

projects/miragesdk/examples/mirage-dhcp.yml

@@ -19,7 +19,7 @@ system:
     command: [/usr/bin/binfmt, -dir, /etc/binfmt.d/, -mount, /binfmt_misc]
   - name: dhcp-client
     network_mode: host
-    image: "mobylinux/dhcp-client:da4e4b37ecd11ce411b0b45bde988281c2b35e3a"
+    image: "mobylinux/dhcp-client:aaf811d77ff8d8b2e16ca4dd9d0a2849ef8977b6"
     capabilities:
      - CAP_NET_ADMIN # to bring eth0 up
      - CAP_NET_RAW   # to read /dev/eth0

projects/miragesdk/src/sdk/init.ml

@@ -78,9 +78,7 @@ module Fd = struct
     let buf = Bytes.create len in
     let rec loop () =
       Lwt_unix.read src.fd buf 0 len >>= fun len ->
-      if len = 0 then
-        (* FIXME: why this ever happen *)
-        Fmt.kstrf Lwt.fail_with "FORWARD[%a => %a]: EOF" pp src pp dst
+      if len = 0 then Lwt.return_unit (* EOF *)
       else (
         Log.debug (fun l ->
             l "FORWARD[%a => %a]: %S (%d)"