linux-kernel - Re: [PATCH 00/11] x86, memblock: Allocate memory near kernel image before SRAT parsed.

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>] [day] [month] [year] [list]

Date:	Mon, 9 Sep 2013 09:58:15 -0400
From:	Tejun Heo <tj@...nel.org>
To:	Wanpeng Li <liwanp@...ux.vnet.ibm.com>
Cc:	rjw@...k.pl, lenb@...nel.org, tglx@...utronix.de, mingo@...e.hu,
	hpa@...or.com, akpm@...ux-foundation.org, trenn@...e.de,
	yinghai@...nel.org, jiang.liu@...wei.com, wency@...fujitsu.com,
	laijs@...fujitsu.com, isimatu.yasuaki@...fujitsu.com,
	izumi.taku@...fujitsu.com, mgorman@...e.de, minchan@...nel.org,
	mina86@...a86.com, gong.chen@...ux.intel.com,
	vasilis.liaskovitis@...fitbricks.com, lwoodman@...hat.com,
	riel@...hat.com, jweiner@...hat.com, prarit@...hat.com,
	zhangyanfei@...fujitsu.com, x86@...nel.org,
	linux-doc@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-mm@...ck.org, linux-acpi@...r.kernel.org
Subject: Re: [PATCH 00/11] x86, memblock: Allocate memory near kernel image
 before SRAT parsed.

Hello,

On Mon, Sep 09, 2013 at 07:56:34PM +0800, Wanpeng Li wrote:
> If allocate from low to high as what this patchset done will occupy the
> precious memory you mentioned?

Yeah, and that'd be the reason why this behavior is dependent on a
kernel option.  That said, allocating some megs on top of kernel isn't
a big deal.  The wretched ISA DMA is mostly gone now and some megs
isn't gonna hurt 32bit DMAs in any noticeable way.  I wouldn't be too
surprised if nobody notices after switching the default behavior to
allocate early mem close to kernel.  Maybe the only case which might
be impacted is 32bit highmem configs, but they're messed up no matter
what anyway and even they shouldn't be affected noticeably if large
mapping is in use.

Thanks.

-- 
tejun
--
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/