Re: [PATCH] gcc-plugins: Change all version strings match kernel

[Guenter Roeck]

On Mon, May 23, 2022 at 12:28:20PM -0700, Kees Cook wrote:
> On Mon, May 23, 2022 at 07:30:54AM -0700, Guenter Roeck wrote:
> > On Tue, May 10, 2022 at 04:54:12PM -0700, Kees Cook wrote:
> > > It's not meaningful for the GCC plugins to track their versions separately
> > > from the rest of the kernel. Switch all versions to the kernel version.
> > > 
> > > Fix mismatched indenting while we're at it.
> > > 
> > > Cc: linux-hardening@xxxxxxxxxxxxxxx
> > > Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
> > 
> > I see random build failures with this patch in linux-next.
> > 
> > Error log:
> > cc1plus: fatal error: ./include/generated/utsrelease.h: No such file or directory
> > 
> > The problem doesn't happen all the time. Is there some missing dependency ?
> 
> I've seen 0-day reports on this too and but I haven't been able to reproduce
> it. AFAICT, utsrelease.h should be generated before the gcc plugins are
> built, but clearly something is wrong.
> 
I have seen it only in my test builds, only on arm targets so far,
and I have been unable to reproduce it manually.

> > >  plugin_cxxflags	= -Wp,-MMD,$(depfile) $(KBUILD_HOSTCXXFLAGS) -fPIC \
> > >  		  -include $(srctree)/include/linux/compiler-version.h \
> > > +		  -include $(objtree)/include/generated/utsrelease.h \
> 
> I wonder if include/generated/utsrelease.h needs to be explicitly added
> as a build dep to the plugin logic?
> 
Looks like it, but I have no idea how to set that up or test/confirm it.

Guenter