kbuild: make: fix if_changed when command contains backslashes

The call if_changed mechanism does not work when the command contains
backslashes.  This basically is an issue with lzo and bzip2 compressed
kernels.  The compressed binaries do not contain the uncompressed image
size, so these use size_append to append the size.  This results in
backslashes in the executed command.  With this if_changed always
detects a change in the command and rebuilds the compressed image even
if nothing has changed.

Fix this by escaping backslashes in make-cmd

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Jan Luebbe <jlu@pengutronix.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Bernhard Walle <bernhard@bwalle.de>
Cc: Michal Marek <mmarek@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
index 6a3ee981931d3c2b4438cff1d220ec2e8039bd7e..afa44595f34868184bef73440f0c68f71c538452 100644 (file)
--- a/scripts/Kbuild.include
+++ b/scripts/Kbuild.include
@@ -209,7 +209,7 @@ endif
 # >$< substitution to preserve $ when reloading .cmd file
 # note: when using inline perl scripts [perl -e '...$$t=1;...']
 # in $(cmd_xxx) double $$ your perl vars
-make-cmd = $(subst \#,\\\#,$(subst $$,$$$$,$(call escsq,$(cmd_$(1)))))
+make-cmd = $(subst \\,\\\\,$(subst \#,\\\#,$(subst $$,$$$$,$(call escsq,$(cmd_$(1))))))
 
 # Find any prerequisites that is newer than target or that does not exist.
 # PHONY targets skipped in both cases.