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Date:   Fri, 25 Oct 2019 11:21:43 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Robert Stupp <snazy@snazy.de>
Cc:     Randy Dunlap <rdunlap@infradead.org>, linux-kernel@vger.kernel.org,
        Linux MM <linux-mm@kvack.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        "Potyra, Stefan" <Stefan.Potyra@elektrobit.com>
Subject: Re: mlockall(MCL_CURRENT) blocking infinitely
Message-ID: <20191025092143.GE658@dhcp22.suse.cz>
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On Thu 24-10-19 16:34:46, Randy Dunlap wrote:
> [adding linux-mm + people]
> 
> I see only one change in the last 4 years:
> 
> commit dedca63504a204dc8410d98883fdc16dffa8cb80
> Author: Potyra, Stefan <Stefan.Potyra@elektrobit.com>
> Date:   Thu Jun 13 15:55:55 2019 -0700
> 
>     mm/mlock.c: mlockall error for flag MCL_ONFAULT
> 
> 
> On 10/24/19 12:36 AM, Robert Stupp wrote:
> > Hi guys,
> > 
> > I've got an issue with `mlockall(MCL_CURRENT)` after upgrading Ubuntu 19.04 to 19.10 - i.e. kernel version change from 5.0.x to 5.3.x.
> > 
> > The following simple program hangs forever with one CPU running at 100% (kernel):

Can you capture everal snapshots of proc/$(pidof $YOURTASK)/stack while
this is happening?
-- 
Michal Hocko
SUSE Labs