Re: [PATCH v5 1/3] Provide in-kernel headers to make extending kernel easier

From: Greg Kroah-Hartman
Date: Tue Apr 16 2019 - 10:22:47 EST


On Tue, Apr 16, 2019 at 09:45:09AM -0400, Steven Rostedt wrote:
> On Tue, 16 Apr 2019 09:32:37 -0400
> Karim Yaghmour <karim.yaghmour@xxxxxxxxxxx> wrote:
>
> > >>> Then we should perhaps make a new file system call tarballs ;-)
> > >>>
> > >>> /sys/kernel/tarballs/
> > >>>
> > >>> and place everything there. That way it removes it from /proc (which is
> > >>> the worse place for that) and also makes it something other than debug.
> > >>> That's what I did for tracefs.
> > >>
> > >> As horrible as that suggestion is, it does kind of make sense :)
> > >>
> > >> We can't put this in debugfs as that's only for debugging and systems
> > >> should never have that mounted for normal operations (users want to
> > >> build ebpf programs), and /proc really should be for processes but that
> > >> horse is long left the barn.
> > >>
> > >> But, I'm willing to consider putting this either in a system-fs-like
> > >> filesystem, or just in sysfs itself, we do have /sys/kernel/ to play
> > >> around in if the main objection is that we should not be cluttering up
> > >> /proc with stuff like this.
> > >>
> > >
> > > I am ok with the suggestion of /sys/kernel for the archive. That also seems
> > > to fit well with the idea that the headers are kernel related and probably
> > > belong here more strictly speaking, than /proc.
> >
> > This makes sense. And if it alleviates concerns regarding extending
> > /proc ABIs then might as well switch to this.
> >
> > Olof, what do you think of this?
>
> BTW, the name "tarballs" was kind of a joke. Probably should come up
> with a better name. Although, I'm fine with tarballsfs ;-)

No need to have this be a separate filesystem, we can use a binary sysfs
file in /sys/kernel/ for this as the kernel is not doing any "parsing"
of the data, it is just dumping it out to userspace.

If I make /sys/kernel/config.gz be the same thing as /proc/config.gz
will you fix up 'make localmodconfig' to use it? :)

thanks,

greg k-h