From 0da7bca639dab94cb744e25820da62d2c0edfb11 Mon Sep 17 00:00:00 2001
From: P J P <ppandit@redhat.com>
Date: Tue, 5 Nov 2013 16:57:04 +1100
Subject: [PATCH] 
 initramfs-read-config_rd_-variables-for-initramfs-compression-fix

I've patched 'gen_initramfs_list.sh' script to check if a selected
compression command is accessible or not; And fall-back to the default
gzip(1) format when it is not.  usr/Makefile also defaults to '.gz' format
when all are enabled.

Signed-off-by: P J P <prasad@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 scripts/gen_initramfs_list.sh | 19 ++++++++++++-------
 usr/Makefile                  |  6 +++---
 2 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/scripts/gen_initramfs_list.sh b/scripts/gen_initramfs_list.sh
index 576197375680..2889a837c40a 100644
--- a/scripts/gen_initramfs_list.sh
+++ b/scripts/gen_initramfs_list.sh
@@ -240,13 +240,18 @@ case "$arg" in
 		output_file="$1"
 		cpio_list="$(mktemp ${TMPDIR:-/tmp}/cpiolist.XXXXXX)"
 		output=${cpio_list}
-		echo "$output_file" | grep -q "\.gz$" && compr="gzip -n -9 -f"
-		echo "$output_file" | grep -q "\.bz2$" && compr="bzip2 -9 -f"
-		echo "$output_file" | grep -q "\.lzma$" && compr="lzma -9 -f"
-		echo "$output_file" | grep -q "\.xz$" && \
-				compr="xz --check=crc32 --lzma2=dict=1MiB"
-		echo "$output_file" | grep -q "\.lzo$" && compr="lzop -9 -f"
-		echo "$output_file" | grep -q "\.lz4$" && compr="lz4 -9 -f"
+		echo "$output_file" | grep -q "\.gz$" && [ -x "/bin/gzip" ] \
+                && compr="gzip -n -9 -f"
+		echo "$output_file" | grep -q "\.bz2$" && [ -x "/bin/bzip2" ] \
+                && compr="bzip2 -9 -f"
+		echo "$output_file" | grep -q "\.lzma$" && [ -x "/bin/lzma" ] \
+                && compr="lzma -9 -f"
+		echo "$output_file" | grep -q "\.xz$" && [ -x "/bin/xz" ] \
+                && compr="xz --check=crc32 --lzma2=dict=1MiB"
+		echo "$output_file" | grep -q "\.lzo$" && [ -x "/bin/lzop" ] \
+                && compr="lzop -9 -f"
+		echo "$output_file" | grep -q "\.lz4$" && [ -x "/bin/lz4" ] \
+                && compr="lz4 -9 -f"
 		echo "$output_file" | grep -q "\.cpio$" && compr="cat"
 		shift
 		;;
diff --git a/usr/Makefile b/usr/Makefile
index 06ad94829b6c..e767f019accf 100644
--- a/usr/Makefile
+++ b/usr/Makefile
@@ -6,9 +6,6 @@ klibcdirs:;
 PHONY += klibcdirs
 
 
-# Gzip
-suffix_$(CONFIG_RD_GZIP)   = .gz
-
 # Bzip2
 suffix_$(CONFIG_RD_BZIP2)  = .bz2
 
@@ -24,6 +21,9 @@ suffix_$(CONFIG_RD_LZO)    = .lzo
 # Lz4
 suffix_$(CONFIG_RD_LZ4)    = .lz4
 
+# Gzip
+suffix_$(CONFIG_RD_GZIP)   = .gz
+
 AFLAGS_initramfs_data.o += -DINITRAMFS_IMAGE="usr/initramfs_data.cpio$(suffix_y)"
 
 # Generate builtin.o based on initramfs_data.o
-- 
2.39.5