Re: [PATCH net-next v3 01/16] mctp: Add MCTP base

[Steven Rostedt]

On Thu, 12 Aug 2021 19:15:24 +0800
Jeremy Kerr <jk@xxxxxxxxxxxxxxxxxxxx> wrote:

> Hi Geert,
> 
> Thanks for the testing!
> 
> > When building an allmodconfig kernel, I got:  
> 
> [...]
> 
> I don't see this on a clean allmodconfig build, nor when building the
> previous commit then the MCTP commit with something like:
> 
>   git checkout bc49d81^
>   make O=obj.allmodconfig allmodconfig
>   make O=obj.allmodconfig -j16
>   git checkout bc49d81
>   make O=obj.allmodconfig -j16
> 
> - but it seems like it might be up to the ordering of a parallel build.
> 
> >From your description, it does sound like it's not regenerating flask.h;  
> the kbuild rules would seem to have a classmap.h -> flask.h dependency:
> 
>   $(addprefix $(obj)/,$(selinux-y)): $(obj)/flask.h
>   
>   quiet_cmd_flask = GEN     $(obj)/flask.h $(obj)/av_permissions.h
>         cmd_flask = scripts/selinux/genheaders/genheaders $(obj)/flask.h $(obj)/av_permissions.h
>   
>   targets += flask.h av_permissions.h
>   $(obj)/flask.h: $(src)/include/classmap.h FORCE
>   	$(call if_changed,flask)
> 
> however, classmap.h is #include-ed as part of the genheaders binary
> build, rather than read at runtime; maybe $(obj)/flask.h should depend
> on the genheaders binary, rather than $(src)/include/classmap.h ?
> 
> If you can reproduce, can you compare the ctimes with:
> 
>   stat scripts/selinux/genheaders/genheaders security/selinux/flask.h

I just hit the exact same issue. I build with O=../build/ and by removing
security/selinux/flask.h and av_permission.h, it built fine afterward.
Appears to be a dependency issue.

-- Steve

> 
> in your object dir?
> 
> Cheers,
> 
> 
> Jeremy
>