linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
* Bug: kbuild always rebuilds compressed images on ARM
@ 2013-10-05 13:17 Russell King - ARM Linux
  2013-10-07 20:03 ` Stephen Boyd
  0 siblings, 1 reply; 2+ messages in thread
From: Russell King - ARM Linux @ 2013-10-05 13:17 UTC (permalink / raw)
  To: linux-arm-kernel

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)
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)

Any ideas why it thinks that the command has changed?

Thanks.

^ permalink raw reply	[flat|nested] 2+ messages in thread

* Bug: kbuild always rebuilds compressed images on ARM
  2013-10-05 13:17 Bug: kbuild always rebuilds compressed images on ARM Russell King - ARM Linux
@ 2013-10-07 20:03 ` Stephen Boyd
  0 siblings, 0 replies; 2+ messages in thread
From: Stephen Boyd @ 2013-10-07 20:03 UTC (permalink / raw)
  To: linux-arm-kernel

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

^ permalink raw reply related	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2013-10-07 20:03 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-10-05 13:17 Bug: kbuild always rebuilds compressed images on ARM Russell King - ARM Linux
2013-10-07 20:03 ` Stephen Boyd

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).