Re: [PATCH v3 2/2] kbuild: Don't mess with the .cache.mk when root

[Nick Desaulniers]

On Mon, Mar 12, 2018 at 11:23 PM Doug Anderson <dianders@xxxxxxxxxxxx>
wrote:

> Hi,

> On Mon, Mar 12, 2018 at 11:16 PM, Ingo Molnar <mingo@xxxxxxxxxx> wrote:
> >
> > * Douglas Anderson <dianders@xxxxxxxxxxxx> wrote:
> >
> >> +# Don't create Makefile caches if running as root since they can't be
deleted
> >> +# easily; in the real world we might be root when doing "sudo make
install"
> >> +ifeq ($(shell id -u),0)
> >> +export KBUILD_NOCACHE := 1
> >> +endif
> >
> > Please don't do this - many prominent kernel developers build their
kernels as
> > root - this makes the build slower for them, and also bifurcates
testing.

> Ah, interesting.  I hadn't realized that!

> I'm OK with dropping this patch myself.  It was mostly addressing a
> potential problem pointed out by Masahiro Yamada when we were talking
> about .cache.mk, but I don't think anyone has actually experienced the
> problems listed in the CL description.

>    /bin/sh: ./.cache.mk: Permission denied

I feel like I've definitely seen that permission error before.

Is there any issue if I:

$ make clean
$ make
$ sudo make install
<hack around>
$ make

Or it's only a problem if:

$ make clean
$ sudo make install
<hack around>
$ make
--
Thanks,
~Nick Desaulniers