[PATCH] Fix kallsyms dependency

[PATCH] Fix kallsyms dependency

[Russell King]

Hi,

It appears that kallsyms data is not updated if the kallsyms program is
changed.  The following patch adds an appropriate dependency.

(if we can make the kallsyms program depend on the targets generated by
it, could we drop it from being always built ?)

diff -up -x BitKeeper -x ChangeSet -x SCCS -x _xlk -x *.orig -x *.rej orig/Makefile linux/Makefile
--- orig/Makefile	Sun Aug  8 12:14:09 2004
+++ linux/Makefile	Sun Aug  8 12:24:27 2004
@@ -581,7 +581,7 @@ cmd_kallsyms = $(NM) -n $< | $(KALLSYMS)
 .tmp_kallsyms1.o .tmp_kallsyms2.o .tmp_kallsyms3.o: %.o: %.S scripts FORCE
 	$(call if_changed_dep,as_o_S)
 
-.tmp_kallsyms%.S: .tmp_vmlinux%
+.tmp_kallsyms%.S: .tmp_vmlinux% $(KALLSYMS)
 	$(call cmd,kallsyms)
 
 .tmp_vmlinux1: $(vmlinux-objs) arch/$(ARCH)/kernel/vmlinux.lds.s FORCE

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:  2.6 PCMCIA      - http://pcmcia.arm.linux.org.uk/
                 2.6 Serial core

Re: [PATCH] Fix kallsyms dependency

[Sam Ravnborg]

On Sun, Aug 08, 2004 at 12:32:30PM +0100, Russell King wrote:
> Hi,
> 
> It appears that kallsyms data is not updated if the kallsyms program is
> changed.  The following patch adds an appropriate dependency.

Added, and implemented your suggestion in scripts/Makefile
with a few other CONFIG selections.

Btw. any specific reason to hack kallsyms? Just curious if something
shows up in this area.

Patch added for reference.

	Sam
	
===== Makefile 1.510 vs edited =====
--- 1.510/Makefile	2004-08-07 21:35:27 +02:00
+++ edited/Makefile	2004-08-08 17:26:49 +02:00
@@ -584,7 +584,7 @@
 .tmp_kallsyms1.o .tmp_kallsyms2.o .tmp_kallsyms3.o: %.o: %.S scripts FORCE
 	$(call if_changed_dep,as_o_S)
 
-.tmp_kallsyms%.S: .tmp_vmlinux%
+.tmp_kallsyms%.S: .tmp_vmlinux% $(KALLSYMS)
 	$(call cmd,kallsyms)
 
 .tmp_vmlinux1: $(vmlinux-objs) arch/$(ARCH)/kernel/vmlinux.lds.s FORCE
===== scripts/Makefile 1.40 vs edited =====
--- 1.40/scripts/Makefile	2004-07-23 01:27:54 +02:00
+++ edited/scripts/Makefile	2004-08-08 17:31:59 +02:00
@@ -5,11 +5,14 @@
 # docproc: 	 Preprocess .tmpl file in order to generate .sgml docs
 # conmakehash:	 Create arrays for initializing the kernel console tables
 
-host-progs	:= conmakehash kallsyms pnmtologo bin2c
+host-progs-$(CONFIG_KALLSYMS) += kallsyms
+host-progs-$(CONFIG_LOGO)     += pnmtologo
+
+host-progs	:= $(host-progs-y) conmakehash bin2c
 always		:= $(host-progs)
 
-subdir-$(CONFIG_MODVERSIONS)	+= genksyms
-subdir-y	+= mod
+subdir-$(CONFIG_MODVERSIONS) += genksyms
+subdir-$(CONFIG_MODULES)     += mod
 
 # Let clean descend into subdirs
 subdir-	+= basic lxdialog kconfig package

Re: [PATCH] Fix kallsyms dependency

[Russell King]

On Sun, Aug 08, 2004 at 05:46:10PM +0200, Sam Ravnborg wrote:
> On Sun, Aug 08, 2004 at 12:32:30PM +0100, Russell King wrote:
> > Hi,
> > 
> > It appears that kallsyms data is not updated if the kallsyms program is
> > changed.  The following patch adds an appropriate dependency.
> 
> Added, and implemented your suggestion in scripts/Makefile
> with a few other CONFIG selections.
> 
> Btw. any specific reason to hack kallsyms? Just curious if something
> shows up in this area.

Yes - later ARM binutils adds extra symbols like "$a" and "$d" to the
symbol table as "mapping symbols" (binutils terminology).  It's not
clear whether these will continue to be visible via normal tools or
not, and I was considering getting kallsyms to filter them out.

Depending on the outcome of the binutils side depends whether or not
I end up modifying kallsyms to ignore these symbols and whether we
end up saying "binutils earlier than <todays latest and greatest
release> can not be used for ARM."

If a release of binutils is imminent which solves both the mapping
symbol visibility problem and the undefined symbol issue, then I
suspect its just all round easier to prevent the ARM kernel being
built with older binutils versions.

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:  2.6 PCMCIA      - http://pcmcia.arm.linux.org.uk/
                 2.6 Serial core