diff --git a/board/aarch64/bananapi-bpi-r3/genimage.cfg.in b/board/aarch64/bananapi-bpi-r3/genimage.cfg.in
index c3734ad4..67d5413a 100644
--- a/board/aarch64/bananapi-bpi-r3/genimage.cfg.in
+++ b/board/aarch64/bananapi-bpi-r3/genimage.cfg.in
@@ -4,16 +4,23 @@ image cfg.ext4 {
         size = 128M
         ext4 {
                 label = "cfg"
+                use-mke2fs = true
+                features = "uninit_bg"
+                extraargs = "-m 0 -i 4096"
         }
 }
 
+# The /var partition will be expanded automatically at first boot
+# to use the full size of the SD-card or eMMC media.
 image var.ext4 {
         empty = true
         temporary = true
-        size = 1G
+        size = 128M
         ext4 {
                 label = "var"
                 use-mke2fs = true
+                features = "uninit_bg"
+                extraargs = "-m 0 -i 4096"
         }
 }
 
diff --git a/board/aarch64/friendlyarm-nanopi-r2s/genimage.cfg.in b/board/aarch64/friendlyarm-nanopi-r2s/genimage.cfg.in
index 6a069181..8c0031b4 100644
--- a/board/aarch64/friendlyarm-nanopi-r2s/genimage.cfg.in
+++ b/board/aarch64/friendlyarm-nanopi-r2s/genimage.cfg.in
@@ -5,17 +5,24 @@ image cfg.ext4 {
 
 	ext4 {
 		label = "cfg"
+                use-mke2fs = true
+                features = "uninit_bg"
+                extraargs = "-m 0 -i 4096"
 	}
 }
 
+# The /var partition will be expanded automatically at first boot
+# to use the full size of the SD-card or eMMC media.
 image var.ext4 {
 	empty = true
 	temporary = true
-	size = 512M
+	size = 128M
 
 	ext4 {
 		label = "var"
-		use-mke2fs = true
+                use-mke2fs = true
+                features = "uninit_bg"
+                extraargs = "-m 0 -i 4096"
 	}
 }
 
diff --git a/board/aarch64/raspberrypi-rpi64/genimage.cfg.in b/board/aarch64/raspberrypi-rpi64/genimage.cfg.in
index 51e45bd2..8e7b356e 100644
--- a/board/aarch64/raspberrypi-rpi64/genimage.cfg.in
+++ b/board/aarch64/raspberrypi-rpi64/genimage.cfg.in
@@ -15,17 +15,24 @@ image cfg.ext4 {
 
 	ext4 {
 		label = "cfg"
+                use-mke2fs = true
+                features = "uninit_bg"
+                extraargs = "-m 0 -i 4096"
 	}
 }
 
+# The /var partition will be expanded automatically at first boot
+# to use the full size of the SD-card or eMMC media.
 image var.ext4 {
 	empty = true
 	temporary = true
-	size = 512M
+	size = 128M
 
 	ext4 {
 		label = "var"
-		use-mke2fs = true
+                use-mke2fs = true
+                features = "uninit_bg"
+                extraargs = "-m 0 -i 4096"
 	}
 }
 
diff --git a/board/common/mkaux.sh b/board/common/mkaux.sh
index 3f139452..0adf9f0f 100755
--- a/board/common/mkaux.sh
+++ b/board/common/mkaux.sh
@@ -11,7 +11,8 @@ image aux.ext4 {
 	ext4 {
 		label = "aux"
 		use-mke2fs = true
-		features = "^metadata_csum,^metadata_csum_seed"
+		features = "^metadata_csum,^metadata_csum_seed,uninit_bg"
+                extraargs = "-m 0 -i 4096"
 	}
 }
 
diff --git a/board/common/rootfs/etc/fstab b/board/common/rootfs/etc/fstab
index 6c56c7f7..fc5850c7 100644
--- a/board/common/rootfs/etc/fstab
+++ b/board/common/rootfs/etc/fstab
@@ -15,9 +15,9 @@ cfgfs		/config		configfs	nofail,noauto		0	0
 # The chosen backing storage for the overlays placed on /cfg, /etc,
 # /home, /root, and /var, are determined dynamically by /usr/libexec/infix/mnt
 # depending on the available devices.
-mnttmp		/mnt/tmp	tmpfs		defaults			0	0
-LABEL=aux	/mnt/aux	auto		noatime,nodiratime,noauto	0	0
-LABEL=var	/mnt/var	auto		noatime,nodiratime,noauto	0	0
-LABEL=cfg	/mnt/cfg	auto		noatime,nodiratime,noauto	0	0
-hostfs		/mnt/host	9p		cache=none,msize=16384,noauto	0	0
-/usr/libexec/infix/mnt#	/cfg	helper		none				0	0
+mnttmp		/mnt/tmp	tmpfs	defaults				0	0
+LABEL=aux	/mnt/aux	auto	noatime,nodiratime,noauto,commit=30,errors=remount-ro	0 0
+LABEL=var	/mnt/var	auto	noatime,nodiratime,noauto,commit=30,errors=remount-ro	0 0
+LABEL=cfg	/mnt/cfg	auto	noatime,nodiratime,noauto,commit=30,errors=remount-ro	0 0
+hostfs		/mnt/host	9p	cache=none,msize=16384,noauto		0	0
+/usr/libexec/infix/mnt#	/cfg	helper	none					0	0
diff --git a/board/common/rootfs/usr/libexec/infix/mnt b/board/common/rootfs/usr/libexec/infix/mnt
index 844db878..d46af0c6 100755
--- a/board/common/rootfs/usr/libexec/infix/mnt
+++ b/board/common/rootfs/usr/libexec/infix/mnt
@@ -19,6 +19,7 @@ set -e
 
 nm=$(basename "$0")
 err=0
+mmc=""
 opt="-k"
 
 # External button or bootloader changed kernel command line
@@ -53,17 +54,22 @@ factory_reset()
 
 is_mmc()
 {
+    [ -n "$mmc" ] && return $mmc
+
     # Check if primary or secondary partition (our rootfs) is on MMC
     for label in primary secondary; do
         devname=$(find_partition_by_label "$label" 2>/dev/null)
         if [ -n "$devname" ]; then
             case "$devname" in
                 mmcblk*)
+		    mmc=0
                     return 0
                     ;;
             esac
         fi
     done
+
+    mmc=1
     return 1
 }
 
@@ -89,8 +95,15 @@ find_partition_by_label()
 
     for diskpath in /sys/class/block/*; do
 	devname=$(basename "$diskpath")
+
+	# Skip partitions, only check whole disks
 	[ -f "$diskpath/partition" ] && continue
 
+	# Skip ram, loop, and other virtual devices
+	case "$devname" in
+	    ram*|loop*|nullb*|dm-*) continue ;;
+	esac
+
 	disk="/dev/$devname"
 	result=$(sgdisk -p "$disk" 2>/dev/null | awk -v label="$label" -v devname="$devname" '
 	    /^  *[0-9]/ {
@@ -275,6 +288,9 @@ mount_rw()
     fi
 
     # TODO: Also look for UBI partitions
+
+    # 
+    tune2fs -c 0 -i 0 LABEL="$1" 2>/dev/null 
     mount LABEL="$1" 2>/dev/null && return 0
 
     return 1