diff --git a/dracut-kdump.sh b/dracut-kdump.sh
index 969ea94..b69bc98 100755
--- a/dracut-kdump.sh
+++ b/dracut-kdump.sh
@@ -1,7 +1,7 @@
 #!/bin/sh
 #
-# The main kdump routine in capture kernel
-#
+# The main kdump routine in capture kernel, bash may not be the
+# default shell. Any code added must be POSIX compliant.
 
 . /lib/dracut-lib.sh
 . /lib/kdump-logger.sh
diff --git a/kdump-lib-initramfs.sh b/kdump-lib-initramfs.sh
index 0cdb465..c1fd75f 100755
--- a/kdump-lib-initramfs.sh
+++ b/kdump-lib-initramfs.sh
@@ -1,7 +1,7 @@
 #!/bin/sh
 #
-# Function and variables used in initramfs environment, POSIX compatible
-#
+# The code in this file will be used in initramfs environment, bash may
+# not be the default shell. Any code added must be POSIX compliant.
 
 DEFAULT_PATH="/var/crash/"
 KDUMP_CONFIG_FILE="/etc/kdump.conf"
diff --git a/kdump-logger.sh b/kdump-logger.sh
index 98c4eea..3fd433d 100755
--- a/kdump-logger.sh
+++ b/kdump-logger.sh
@@ -34,6 +34,8 @@
 # First of all you have to start with dlog_init() function which initializes
 # required variables. Don't call any other logging function before that one!
 #
+# The code in this file might be run in an environment without bash.
+# Any code added must be POSIX compliant.
 
 # Define vairables for the log levels in this module.
 kdump_stdloglvl=""