On 10/05/13 06:17, Russell King - ARM Linux wrote: > Hi, > > I've noticed that kbuild always rebuilds the compressed piggy image > on ARM. Here's the output from running make with V=2: > > CALL /home/rmk/git/linux-rmk/scripts/checksyscalls.sh - due to target missing > CHK include/generated/compile.h > Kernel: arch/arm/boot/Image is ready > Building modules, stage 2. > LZO arch/arm/boot/compressed/piggy.lzo - due to command line change > MODPOST 17 modules - due to target is PHONY > AS arch/arm/boot/compressed/piggy.lzo.o - due to: arch/arm/boot/compressed/piggy.lzo > LD arch/arm/boot/compressed/vmlinux - due to: arch/arm/boot/compressed/piggy.lzo.o > OBJCOPY arch/arm/boot/zImage - due to: arch/arm/boot/compressed/vmlinux > Kernel: arch/arm/boot/zImage is ready > > and with V=1: > > ... > make -f /home/rmk/git/linux-rmk/scripts/Makefile.build obj=arch/arm/boot/compressed arch/arm/boot/compressed/vmlinux > make -f /home/rmk/git/linux-rmk/scripts/Makefile.modpost > find .tmp_versions -name '*.mod' | xargs -r grep -h '\.ko$' | sort -u | sed 's/\.ko$/.o/' | scripts/mod/modpost -m -a -o /home/rmk/git/build/imx6/Module.symvers -S -s -T - > (cat arch/arm/boot/compressed/../Image | lzop -9 && printf \\010\\224\\034\\002) > arch/arm/boot/compressed/piggy.lzo || (rm -f arch/arm/boot/compressed/piggy.lzo ; false) There are double slashes here '\\' > make -f /home/rmk/git/linux-rmk/scripts/Makefile.fwinst obj=firmware __fw_modbuild > ... > > The arch/arm/boot/compressed/.piggy.lzo.cmd file contains this: > > cmd_arch/arm/boot/compressed/piggy.lzo := (cat arch/arm/boot/compressed/../Image | lzop -9 && printf \\\\010\\\\224\\\\034\\\\002) > arch/arm/boot/compressed/piggy.lzo || (rm -f arch/arm/boot/compressed/piggy.lzo ; false) But then there are quadruple slashes here '\\\\'. That seems to be causing kbuild to rebuild each time. > > Any ideas why it thinks that the command has changed? This hack seems to work, but I'm not convinced it's the right solution. diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index 547e15d..bfc0b79 100644 --- 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 \#,\\\#,$(subst $$,$$$$,$(call escsq,$(cmd_$(1)))))) +make-cmd = $(subst \#,\\\#,$(subst $$,$$$$,$(call escsq,$(cmd_$(1))))) # Find any prerequisites that is newer than target or that does not exist. # PHONY targets skipped in both cases. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
