[PATCH 4.16 278/279] ARM: replace unnecessary perl with sed and the shell $(( )) operator

[Greg Kroah-Hartman]

4.16-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>

[ Upstream commit 6cea14f55474ec71f1098228e0ae5dd2a8f22c0a ]

You can build a kernel in a cross compiling environment that doesn't
have perl in the $PATH. Commit 429f7a062e3b broke that for 32 bit
ARM. Fix it.

As reported by Stephen Rothwell, it appears that the symbols can be
either part of the BSS section or absolute symbols depending on the
binutils version.  When they're an absolute symbol, the $(( ))
operator errors out and the build fails.  Fix this as well.

Fixes: 429f7a062e3b ("ARM: decompressor: fix BSS size calculation")
Reported-by: Rob Landley <rob@xxxxxxxxxxx>
Reported-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Acked-by: Rob Landley <rob@xxxxxxxxxxx>
Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 arch/arm/boot/compressed/Makefile |    8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

--- a/arch/arm/boot/compressed/Makefile
+++ b/arch/arm/boot/compressed/Makefile
@@ -117,11 +117,9 @@ ccflags-y := -fpic -mno-single-pic-base
 asflags-y := -DZIMAGE
 
 # Supply kernel BSS size to the decompressor via a linker symbol.
-KBSS_SZ = $(shell $(CROSS_COMPILE)nm $(obj)/../../../../vmlinux | \
-		perl -e 'while (<>) { \
-			$$bss_start=hex($$1) if /^([[:xdigit:]]+) B __bss_start$$/; \
-			$$bss_end=hex($$1) if /^([[:xdigit:]]+) B __bss_stop$$/; \
-		}; printf "%d\n", $$bss_end - $$bss_start;')
+KBSS_SZ = $(shell echo $$(($$($(CROSS_COMPILE)nm $(obj)/../../../../vmlinux | \
+		sed -n -e 's/^\([^ ]*\) [AB] __bss_start$$/-0x\1/p' \
+		       -e 's/^\([^ ]*\) [AB] __bss_stop$$/+0x\1/p') )) )
 LDFLAGS_vmlinux = --defsym _kernel_bss_size=$(KBSS_SZ)
 # Supply ZRELADDR to the decompressor via a linker symbol.
 ifneq ($(CONFIG_AUTO_ZRELADDR),y)