diff --git a/modules/installer/cd-dvd/iso-image.nix b/modules/installer/cd-dvd/iso-image.nix
index 7b050f8dd6a..cf76151c2ae 100644
--- a/modules/installer/cd-dvd/iso-image.nix
+++ b/modules/installer/cd-dvd/iso-image.nix
@@ -205,7 +205,9 @@ in
     else
       [ config.boot.kernelPackages.aufs ];
 
-  boot.initrd.kernelModules = [ "aufs" "squashfs" "iso9660" "loop" ];
+  boot.initrd.availableKernelModules = [ "aufs" "squashfs" "iso9660" ];
+
+  boot.initrd.kernelModules = [ "loop" ];
 
   boot.kernelModules = pkgs.stdenv.lib.optional config.isoImage.makeEfiBootable "efivars";
 
diff --git a/modules/system/boot/stage-1-init.sh b/modules/system/boot/stage-1-init.sh
index 33eaee826aa..cc12ccaa738 100644
--- a/modules/system/boot/stage-1-init.sh
+++ b/modules/system/boot/stage-1-init.sh
@@ -184,21 +184,28 @@ onACPower() {
 
 # Check the specified file system, if appropriate.
 checkFS() {
+    local device="$1"
+    local fsType="$2"
+    
     # Only check block devices.
-    if ! test -b "$device"; then return 0; fi
-
-    FSTYPE=$(blkid -o value -s TYPE "$device" || true)
+    if [ ! -b "$device" ]; then return 0; fi
 
     # Don't check ROM filesystems.
-    if test "$FSTYPE" = iso9660 -o "$FSTYPE" = udf; then return 0; fi
+    if [ "$fsType" = iso9660 -o "$fsType" = udf ]; then return 0; fi
+
+    # If we couldn't figure out the FS type, then skip fsck.
+    if [ "$fsType" = auto ]; then
+        echo 'cannot check filesystem with type "auto"!'
+        return 0
+    fi
 
     # Optionally, skip fsck on journaling filesystems.  This option is
     # a hack - it's mostly because e2fsck on ext3 takes much longer to
     # recover the journal than the ext3 implementation in the kernel
     # does (minutes versus seconds).
     if test -z "@checkJournalingFS@" -a \
-        \( "$FSTYPE" = ext3 -o "$FSTYPE" = ext4 -o "$FSTYPE" = reiserfs \
-        -o "$FSTYPE" = xfs -o "$FSTYPE" = jfs \)
+        \( "$fsType" = ext3 -o "$fsType" = ext4 -o "$fsType" = reiserfs \
+        -o "$fsType" = xfs -o "$fsType" = jfs \)
     then
         return 0
     fi
@@ -210,7 +217,9 @@ checkFS() {
         return 0
     fi
 
-    FSTAB_FILE="/etc/mtab" fsck -V -C -a "$device"
+    echo "checking $device..."
+
+    fsck -V -a "$device"
     fsckResult=$?
 
     if test $(($fsckResult | 2)) = $fsckResult; then
@@ -240,7 +249,16 @@ mountFS() {
     local options="$3"
     local fsType="$4"
 
-    checkFS "$device"
+    if [ "$fsType" = auto ]; then
+        fsType=$(blkid -o value -s TYPE "$device")
+        if [ -z "$fsType" ]; then fsType=auto; fi
+    fi
+
+    echo "$device /mnt-root$mountPoint $fsType $options" >> /etc/fstab
+
+    checkFS "$device" "$fsType"
+
+    echo "mounting $device on $mountPoint..."
 
     mkdir -p "/mnt-root$mountPoint" || true
 
@@ -250,7 +268,7 @@ mountFS() {
         if [ "$fsType" = "nfs" ]; then
           nfsmount "$device" "/mnt-root$mountPoint" && break
         else
-          mount -t "$fsType" -o "$options" "$device" "/mnt-root$mountPoint" && break
+          mount "/mnt-root$mountPoint" && break
         fi
         if [ "$fsType" != cifs -o "$n" -ge 10 ]; then fail; break; fi
         echo "retrying..."
@@ -311,8 +329,6 @@ while read -u 3 mountPoint; do
     # doing something with $device right now.
     udevadm settle || true
 
-    echo "mounting $device on $mountPoint..."
-
     mountFS "$device" "$mountPoint" "$options" "$fsType"
 done