linux-kernel - RE: [RFC PATCH 10/12] mm: add the buddy system interface

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

Date:	Fri, 26 Jun 2015 18:42:41 +0000
From:	"Luck, Tony" <tony.luck@...el.com>
To:	Xishi Qiu <qiuxishi@...wei.com>,
	Kamezawa Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
CC:	Andrew Morton <akpm@...ux-foundation.org>,
	"nao.horiguchi@...il.com" <nao.horiguchi@...il.com>,
	Yinghai Lu <yinghai@...nel.org>,
	"H. Peter Anvin" <hpa@...or.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	"mingo@...e.hu" <mingo@...e.hu>, Xiexiuqi <xiexiuqi@...wei.com>,
	Hanjun Guo <guohanjun@...wei.com>,
	Linux MM <linux-mm@...ck.org>,
	LKML <linux-kernel@...r.kernel.org>
Subject: RE: [RFC PATCH 10/12] mm: add the buddy system interface

> gfpflags_to_migratetype()
>   if (memory_mirror_enabled()) { /* We want to mirror all unmovable pages */
>       if (!(gfp_mask & __GFP_MOVABLE))
>            return MIGRATE_MIRROR
>   }

I'm not sure that we can divide memory into just two buckets of "mirrored" and "movable".

My expectation is that there will be memory that is neither mirrored, nor movable.  We'd
allocate that memory to user proceses.  Uncorrected errors in that memory would result
in the death of the process (except in the case where the page is a clean copy mapped from
a disk file ... e.g. .text mapping instructions from an executable).  Linux would offline
the affected 4K page so as not to hit the problem again.

-Tony
--
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/