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

Joao Moreira
2019-03-26T14:41:31Z

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@suse.de>

---

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
>