add kenrel command line cookie to mips-vm script

now we can have flashable and tftpboot in the same configuration

devices/gl-mt300n-v2/default.nix

@@ -167,6 +167,10 @@
           BRIDGE_VLAN_FILTERING = "y";
           BRIDGE_IGMP_SNOOPING = "y";
 
+          WATCHDOG = "y";
+          RALINK_WDT = "y";  # watchdog
+          MT7621_WDT = "y";  # or it might be this one
+
           GPIOLIB="y";
           GPIO_MT7621 = "y";
 

examples/arhcive.nix

@@ -34,7 +34,8 @@ in rec {
   imports = [
     ../modules/tftpboot.nix
     ../modules/wlan.nix
-    # ./modules/flashable.nix
+    ../modules/flashable.nix
+    ../modules/kexecboot.nix
   ];
 
   hostname = "arhcive";
@@ -181,12 +182,13 @@ in rec {
       };
       configFile = writeText "rsync.conf" ''
         pid file = /run/rsyncd.pid
-        uid = store
+        uid = backup
         [srv]
           path = /srv
           use chroot = yes
           auth users = backup
           read only = false
+          gid = backup
           secrets file = ${secrets_file}/.outputs/secrets
       '';
     in longrun {
@@ -201,12 +203,12 @@ in rec {
       ] ;
     };
 
-    services.default = target {
+  services.default = target {
     name = "default";
     contents =
       let links = config.hardware.networkInterfaces;
       in with config.services; [
-        links.lo links.eth links.wlan
+        links.lo
         defaultroute4
         resolvconf
         sshd
@@ -222,9 +224,12 @@ in rec {
     # ];
   };
 
-  users.store = {
+  users.backup = {
     uid=500; gid=500; gecos="Storage owner"; dir="/srv";
-    shell="/dev/null"; # authorizedKeys = [];
+    shell="/dev/null";
+  };
+  groups.backup = {
+    gid=500; usernames = ["backup"];
   };
 
   defaultProfile.packages = with pkgs; [e2fsprogs strace tcpdump ];

modules/flashable.nix

@@ -17,6 +17,10 @@ in {
       };
     };
 
+    programs.busybox.applets = [
+      "flashcp"
+    ];
+
     outputs.firmware =
       let o = config.outputs; in
       pkgs.runCommand "firmware" {} ''

modules/kexecboot.nix

@@ -26,7 +26,6 @@ in {
 
     outputs.boot-sh =
       let
-        inherit (pkgs) kexec-tools;
         inherit (pkgs.lib.trivial) toHexString;
         inherit (config.outputs) squashfs kernel;
         cmdline = concatStringsSep " " config.boot.commandLine;

overlay.nix

@@ -17,6 +17,13 @@ extraPkgs // {
   strace = prev.strace.override { libunwind = null; };
 
   kexec-tools = prev.kexec-tools.overrideAttrs(o: {
+    # For kexecboot we copy kexec into a ramdisk on the system being
+    # upgraded from. This is more likely to work if kexec is
+    # statically linked so doesn't have dependencies on store paths that
+    # may not exist on that machine. (We can't nix-copy-closure as
+    # the store may not be on a writable filesystem)
+    LDFLAGS = "-static";
+
     patches = o.patches ++ [
       (fetchpatch {
         # merge user command line options into DTB chosen

pkgs/mips-vm/mips-vm.sh

@@ -29,7 +29,7 @@ echo $QEMU_OPTIONS
 qemu-system-mips \
     -M malta -m 256 \
     -echr 16 \
-    -append "default console=ttyS0,38400n8 panic=10 oops=panic init=$INIT loglevel=8 root=/dev/vda" \
+    -append "liminix default console=ttyS0,38400n8 panic=10 oops=panic init=$INIT loglevel=8 root=/dev/vda" \
     -drive file=$2,format=raw,readonly=on,if=virtio \
     -netdev socket,id=access,mcast=230.0.0.1:1234,localaddr=127.0.0.1 \
     -device virtio-net-pci,disable-legacy=on,disable-modern=off,netdev=access,mac=ba:ad:1d:ea:21:02 \