linux-kernel - Re: [PATCH RFC v2 4/4] mm/mempolicy: add nodes_empty check in SYSC_migrate

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: <alpine.DEB.2.20.1711080900050.6161@nuc-kabylake>
Date:   Wed, 8 Nov 2017 09:02:36 -0600 (CST)
From:   Christopher Lameter <cl@...ux.com>
To:     Yisheng Xie <xieyisheng1@...wei.com>
cc:     Vlastimil Babka <vbabka@...e.cz>, akpm@...ux-foundation.org,
        mhocko@...e.com, mingo@...nel.org, rientjes@...gle.com,
        n-horiguchi@...jp.nec.com, salls@...ucsb.edu, linux-mm@...ck.org,
        linux-kernel@...r.kernel.org, tanxiaojun@...wei.com,
        linux-api@...r.kernel.org, Andi Kleen <ak@...ux.intel.com>
Subject: Re: [PATCH RFC v2 4/4] mm/mempolicy: add nodes_empty check in
 SYSC_migrate_pages

On Wed, 8 Nov 2017, Yisheng Xie wrote:

> Another case is current process is *not* the same as target process, and
> when current process try to migrate pages of target process from old_nodes
> to new_nodes, the new_nodes should be a subset of target process cpuset.

The caller of migrate_pages should be able to migrate the target process
pages anywhere the caller can allocate memory. If that is outside the
target processes cpuset then that is fine. Pagecache pages that are not
allocated by the target process already are not subject to the target
processes restriction. So this is not that unusual.