Re: [PATCH v3 0/2] Ajust lockdep static allocations for sparc

From: Peter Zijlstra
Date: Tue Nov 29 2016 - 07:29:34 EST


On Tue, Nov 29, 2016 at 12:52:04PM +0100, Geert Uytterhoeven wrote:
> > Nah, users don't need more senseless options. This is really only useful
> > for dinky platforms or platforms with limited static image size (like
> > sparc64).
> >
> > If you make this user selectable, someone will do, and then an endless
> > stream of table not big enough warnings will be posted.
> >
> > Also, its only 4MB (IIRC), so who cares.
>
> I care :-)
>
> Not because of platforms with not limited memory, but because of platforms
> with boot loaders that have silly kernel size limitations, and start
> scribbling over the DTB or even theirselves when copying a large kernel image.

Right, that's the weird platforms clause above, and those can select the
option.

> BTW, is there any particular reason these huge arrays are in BSS, and not
> allocated dynamically? That would solve my problems as well...

Is there a memory allocator available before _any_ locks are used, and
that itself also doesn't use locks?