linux-kernel - Re: [PATCH 1/1] arm64: mm: add config options for page table configuration

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: <20161208100014.GE33075@MBP.local>
Date:   Thu, 8 Dec 2016 10:00:15 +0000
From:   Catalin Marinas <catalin.marinas@....com>
To:     Scott Branden <scott.branden@...adcom.com>
Cc:     Arnd Bergmann <arnd@...db.de>, Olof Johansson <olof@...om.net>,
        Will Deacon <will.deacon@....com>,
        BCM Kernel Feedback <bcm-kernel-feedback-list@...adcom.com>,
        linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH 1/1] arm64: mm: add config options for page table
 configuration

On Wed, Dec 07, 2016 at 11:40:00AM -0800, Scott Branden wrote:
> Make MAX_PHYSMEM_BITS and SECTIONS_SIZE_BITS configurable by adding
> config options.
> Default to current settings currently defined in sparesmem.h.
> For systems wishing to save memory the config options can be overridden.
> Example, changing MAX_PHYSMEM_BITS from 48 to 36 at the same time as
> changing SECTION_SIZE_BITS from 30 to 26 frees 13MB of memory.

I'm not keen on such change, it's a big departure from the single Image
aims. I would rather reduce SECTION_SIZE_BITS permanently where
feasible, like in this patch:

http://lkml.kernel.org/r/1465821119-3384-1-git-send-email-jszhang@marvell.com

-- 
Catalin