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
| ||
|
Message-ID: <1527959.PBej7RR7ig@vostro.rjw.lan> Date: Sun, 14 Sep 2014 18:43:31 +0200 From: "Rafael J. Wysocki" <rjw@...ysocki.net> To: Tejun Heo <tj@...nel.org> Cc: Michal Hocko <mhocko@...e.cz>, Cong Wang <xiyou.wangcong@...il.com>, LKML <linux-kernel@...r.kernel.org>, David Rientjes <rientjes@...gle.com>, Andrew Morton <akpm@...ux-foundation.org> Subject: Re: [Patch v4 1/2] freezer: check OOM kill while being frozen On Saturday, September 13, 2014 08:59:35 AM Tejun Heo wrote: > On Thu, Sep 11, 2014 at 06:30:04PM +0200, Michal Hocko wrote: > > > I am wondering if the folllowing check makes any sense with regarding > > > to rule out PM freeze: > > > > > > if ((!pm_nosig_freezing && !pm_freezing) && > > > cgroup_freezing(current) && test_thread_flag(TIF_MEMDIE)) > > > return true; > > Doesn't this mean that if PM freezing and OOM killing race each other, > the system may hang? Driver PM operation may try to allocate memory > -> triggers OOM -> OOM killer selects an already frozen task -> > nothing happens. I wonder whether OOM killing and PM operations > should be mutually exclusive at a higher level. e.g. make OOM killing > always override freezing but let hibernation abort operation before > taking snapshot if OOM killing has happened since the beginning of the > PM operation. As Michal noted, we do oom_killer_disable() in freeze_processes(), so the scenario above cannot actually happen to my eyes. Or am I missing anything? -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- 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/
Powered by blists - more mailing lists