[PATCH v2] modules_install: warn when missing System.map file

[Randy Dunlap]

From: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>

If there is no System.map file for "make modules_install",
scripts/depmod.sh will silently exit with success, having done
nothing.  Since this is an unexpected situation, change it to
report a Warning for the missing file.  The behavior is not
changed except for the Warning message.

The (previous) silent success and new Warning can be reproduced
by:
$ make mrproper; make defconfig
$ make modules; make modules_install

and since System.map is produced by "make vmlinux", the steps
above omit producing the System.map file.

Reported-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
---
v2: add Yamada-san's suggestions for >&2 and Skipping depmod.

 scripts/depmod.sh |    1 +
 1 file changed, 1 insertion(+)

--- lnx-419-rc1.orig/scripts/depmod.sh
+++ lnx-419-rc1/scripts/depmod.sh
@@ -11,6 +11,7 @@ DEPMOD=$1
 KERNELRELEASE=$2
 
 if ! test -r System.map ; then
+	echo "Warning: modules_install: missing 'System.map' file. Skipping depmod." >&2
 	exit 0
 fi