Re: [PATCH v2 2/8] kbuild: Support for Symbols.list creation

[Joao Moreira]

On 3/20/19 4:08 PM, Miroslav Benes wrote:
> > > diff --git a/scripts/Makefile.build b/scripts/Makefile.build
> > > index fd03d60f6c5a..1e28ad21314c 100644
> > > --- a/scripts/Makefile.build
> > > +++ b/scripts/Makefile.build
> > > @@ -247,6 +247,11 @@ cmd_gen_ksymdeps = \
> > >   	$(CONFIG_SHELL) $(srctree)/scripts/gen_ksymdeps.sh $@ >> $(dot-target).cmd
> > >   endif
> > >   
> > > +ifdef CONFIG_LIVEPATCH
> > > +cmd_livepatch = $(if $(LIVEPATCH_$(basetarget).o),			\
> > > +	$(shell touch $(MODVERDIR)/$(basetarget).livepatch))
> > > +endif
> > > +
> > >   define rule_cc_o_c
> > >   	$(call cmd,checksrc)
> > >   	$(call cmd_and_fixdep,cc_o_c)
> > > @@ -283,6 +288,7 @@ $(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) F
> > >   	$(call if_changed_rule,cc_o_c)
> > >   	@{ echo $(@:.o=.ko); echo $@; \
> > >   	   $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
> > > +	$(call cmd_livepatch)
> > >   
> > >   quiet_cmd_cc_lst_c = MKLST   $@
> > >         cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
> >
> > Since cmd_livepatch is only called for single-used-m, does this mean
> > that we can only klp-convert single object file livepatch modules?
> >
> > I stumbled upon this when trying to create a self-test module that
> > incorporated two object files.  I tried adding a $(call cmd_livepatch)
> > in the recipe for $(obj)/%.o, but that didn't help.  My kbuild foo
> > wasn't good enough to figure this one out.
>
> I looked at my original code and it is a bit different there. I placed it
> under rule_cc_o_c right after objtool command. If I remember correctly
> this is the correct recipe for .c->.o. Unfortunately I forgot the details
> and there is of course nothing about it in my notes.
>
> Does it help?
>
> Joao, is there a reason you moved it elsewhere?

Hi,

Unfortunately I can't remember why the chunk was moved to where it is in 
this version of the patch, sorry. Yet, I did try to move this into the 
rule cc_o_c and it seemed to work with not damage.

Joe, would you kindly verify and squash properly the patch below, which 
places cmd_livepatch in rule_cc_o_c?

Thank you.

Subject: [PATCH] Move cmd_klp_convert to the right place 



Signed-off-by: Joao Moreira <jmoreira@xxxxxxx> 

--- 

 scripts/Makefile.build | 2 +- 

 1 file changed, 1 insertion(+), 1 deletion(-) 



diff --git a/scripts/Makefile.build b/scripts/Makefile.build 

index 1e28ad21314c..5f66106a47d6 100644 

--- a/scripts/Makefile.build 

+++ b/scripts/Makefile.build 

@@ -260,6 +260,7 @@ define rule_cc_o_c 

        $(call cmd,objtool) 

        $(call cmd,modversions_c) 

        $(call cmd,record_mcount) 

+       $(call cmd,livepatch) 

 endef 



 define rule_as_o_S 

@@ -288,7 +289,6 @@ $(single-used-m): $(obj)/%.o: $(src)/%.c 
$(recordmcount_source) $(objtool_dep) F
        $(call if_changed_rule,cc_o_c) 

        @{ echo $(@:.o=.ko); echo $@; \ 

           $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod) 

-       $(call cmd_livepatch) 



 quiet_cmd_cc_lst_c = MKLST   $@ 

       cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \ 

--

2.16.4


> Miroslav