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Date:   Thu, 26 Mar 2020 16:16:38 -0400
From:   Rafael Aquini <aquini@redhat.com>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     Michal Hocko <mhocko@kernel.org>,
        Shakeel Butt <shakeelb@google.com>,
        LKML <linux-kernel@vger.kernel.org>,
        linux-kselftest@vger.kernel.org, shuah@kernel.org,
        Eric B Munson <emunson@akamai.com>
Subject: Re: [PATCH] tools/testing/selftests/vm/mlock2-tests: fix mlock2
 false-negative errors
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On Thu, Mar 26, 2020 at 12:58:09PM -0700, Andrew Morton wrote:
> On Thu, 26 Mar 2020 07:49:09 +0100 Michal Hocko <mhocko@kernel.org> wrote:
> 
> > On Wed 25-03-20 17:49:49, Andrew Morton wrote:
> > > On Tue, 24 Mar 2020 11:49:10 -0400 Rafael Aquini <aquini@redhat.com> wrote:
> > > 
> > > > Thanks Michal!
> > > > 
> > > >  
> > > > Acked-by: Rafael Aquini <aquini@redhat.com>
> > > 
> > > I'll add
> > > Fixes: 9c4e6b1a7027f ("mm, mlock, vmscan: no more skipping pagevecs")
> > 
> > Wouldn't be this misleading? It would suggest that this commit is
> > somehow incorrect. I would consider b3b0d09c7a23 ("selftests: vm: add
> > tests for lock on fault") to be a better fit.
> 
> Yes, it's a bit misleading.
> 
> Or maybe not.  b3b0d09c7a23 was merged in 2015 and worked OK (afaik)
> until 9c4e6b1a7027f came along in 2020.  So arguably, 2020's
> 9c4e6b1a7027f was correct but incomplete, since it failed to repair the
> impact upon the test code.
>

That's correct, and it was my reading, as well.
 
> I don't think that kernels prior to 2020's 9c4e6b1a7027f require this
> change(?), so we only need to backport this into 5.6.x, which is what
> my proposed Fixes: and cc:stable expresses.
> 

Agreed

-- Rafael