linux-kernel - Re: [PATCH repost] mm,x86: remove debug_pagealloc

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]

Message-ID: <20111205150019.GA5434@redhat.com>
Date:	Mon, 5 Dec 2011 16:00:22 +0100
From:	Stanislaw Gruszka <sgruszka@...hat.com>
To:	Ingo Molnar <mingo@...e.hu>
Cc:	linux-mm@...ck.org, x86@...nel.org, linux-kernel@...r.kernel.org,
	Mel Gorman <mgorman@...e.de>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Ingo Molnar <mingo@...hat.com>,
	"H. Peter Anvin" <hpa@...or.com>,
	Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [PATCH repost] mm,x86: remove debug_pagealloc_enabled

On Mon, Dec 05, 2011 at 12:06:56PM +0100, Ingo Molnar wrote:
> 
> * Stanislaw Gruszka <sgruszka@...hat.com> wrote:
> 
> > When (no)bootmem finish operation, it pass pages to buddy allocator.
> > Since debug_pagealloc_enabled is not set, we will do not protect pages,
> > what is not what we want with CONFIG_DEBUG_PAGEALLOC=y.
> > 
> > To fix remove debug_pagealloc_enabled. That variable was introduced by
> > commit 12d6f21e "x86: do not PSE on CONFIG_DEBUG_PAGEALLOC=y" to get
> > more CPA (change page attribude) code testing. But currently we have
> > CONFIG_CPA_DEBUG, which test CPA.
> > 
> > Signed-off-by: Stanislaw Gruszka <sgruszka@...hat.com>
> > Acked-by: Mel Gorman <mgorman@...e.de>
> > ---
> >  arch/x86/mm/pageattr.c |    6 ------
> >  include/linux/mm.h     |   10 ----------
> >  init/main.c            |    5 -----
> >  mm/debug-pagealloc.c   |    3 ---
> >  4 files changed, 0 insertions(+), 24 deletions(-)
> 
> I'm getting this boot crash with the patch applied:

I'm sorry for breaking the boot. I tried to reproduce problem on my
laptop, but failed. I plan to test patch with your config on some other
machines.

On the meantime can you test attached incremental patch and see if it
workaround the crash? I suspect memblock reuse pages that it passed
already to buddy allocator.

Thanks
Stanislaw

View attachment "init_highmem_pages_first.patch" of type "text/plain" (737 bytes)