linux-kernel - Re: [patch 2/3] CONFIG_HIGHPTE vs. sub-page page tables.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 2 Jan 2008 22:24:38 +0100 (CET)
From:	Geert Uytterhoeven <geert@...ux-m68k.org>
To:	Christoph Hellwig <hch@...radead.org>
cc:	schwidefsky@...ibm.com, akpm@...ux-foundation.org,
	linux-kernel@...r.kernel.org, linux-arch@...r.kernel.org,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>
Subject: Re: [patch 2/3] CONFIG_HIGHPTE vs. sub-page page tables.

On Wed, 2 Jan 2008, Christoph Hellwig wrote:
> On Mon, Nov 12, 2007 at 03:30:11PM +0100, schwidefsky@...ibm.com wrote:
> > From: Martin Schwidefsky <schwidefsky@...ibm.com>
> > Solution: The only solution I found to this dilemma is a new typedef:
> > a pgtable_t. For s390 pgtable_t will be a (pte *) - to be introduced
> > with a later patch. For everybody else it will be a (struct page *).
> > The additional problem with the initialization of the ptl lock and the
> > NR_PAGETABLE accounting is solved with a constructor pgtable_page_ctor
> > and a destructor pgtable_page_dtor. The page table allocation and free
> > functions need to call these two whenever a page table page is allocated
> > or freed. pmd_populate will get a pgtable_t instead of a struct page
> > pointer. To get the pgtable_t back from a pmd entry that has been
> > installed with pmd_populate a new function pmd_pgtable is added. It
> > replaces the pmd_page call in free_pte_range and apply_to_pte_range.
> 
> Can we please just nuke CONFIG_HIGHPTE?  There's only been a small
> amount of 32bit machines with so much memory that they'd need it
> and they can happily stay on the currently supported enterprise
> distro releases instead of dragging this cruft around forever.

And all MMU-equipped FR-V machines with more than 256 MiB of RAM,
according to arch/frv/Kconfig?

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@...ux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/