linux-kernel - Re: [PATCH 1/1] pagemap clear_refs: modify to specify anon or mapped vma clearing

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:	Tue, 28 Jul 2009 16:52:45 -0700
From:	Andrew Morton <akpm@...ux-foundation.org>
To:	"Moussa A. Ba" <moussa.a.ba@...il.com>
Cc:	linux-kernel@...r.kernel.org, rientjes@...gle.com,
	xiyou.wangcong@...il.com, adobriyan@...il.com, mpm@...enic.com,
	mel@....ul.ie, yinghan@...gle.com, npiggin@...e.de,
	jaredeh@...il.com
Subject: Re: [PATCH 1/1] pagemap clear_refs: modify to specify anon or
 mapped vma clearing

On Tue, 28 Jul 2009 15:52:05 -0700
"Moussa A. Ba" <moussa.a.ba@...il.com> wrote:

> This patch adds anonymous and file backed filters to the clear_refs interface.
> echo 1 > /proc/PID/clear_refs resets the bits on all pages
> echo 2 > /proc/PID/clear_refs resets the bits on anonymous pages only
> echo 3 > /proc/PID/clear_refs resets the bits on file backed pages only
> Any other value is ignored

The changelog is missing any rationale for making this change. 
Originally we were told that it "makes the clear_refs proc interface a
bit more versatile", but that's a bit thin.

How do we justify making this change to Linux?  What value does it
have?  Can you describe a usage scenario which would help people
understand the usefulness of the change?

Thanks.
--
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/