diff --git a/conf/machine/am335x-evm.conf b/conf/machine/am335x-evm.conf
index ba452dbd..9c871c2d 100644
--- a/conf/machine/am335x-evm.conf
+++ b/conf/machine/am335x-evm.conf
@@ -25,7 +25,7 @@ SERIAL_CONSOLES_CHECK = "${SERIAL_CONSOLES}"
 # UBI: logical eraseblock size:    126976 bytes
 # from ubiattach stdout:
 # UBI device number 0, total 1988 LEBs
-MKUBIFS_ARGS = "-F -m 2048 -e 126976 -c 8300"
+MKUBIFS_ARGS = "-F -m 2048 -e 126976 -c 8600"
 
 # do ubiattach /dev/ubi_ctrl -m 7 -O 2048
 # from dmesg:
diff --git a/conf/machine/am437x-evm.conf b/conf/machine/am437x-evm.conf
index 06ce4f8b..63c2b9cc 100644
--- a/conf/machine/am437x-evm.conf
+++ b/conf/machine/am437x-evm.conf
@@ -22,7 +22,7 @@ SERIAL_CONSOLE = "115200 ttyS0"
 # UBI: logical eraseblock size:    253952 bytes
 # from ubiattach stdout:
 # UBI device number 0, total 994 LEBs
-MKUBIFS_ARGS = "-F -m 4096 -e 253952 -c 4000"
+MKUBIFS_ARGS = "-F -m 4096 -e 253952 -c 4200"
 
 # do ubiattach /dev/ubi_ctrl -m 11 -O 4096
 # from dmesg: