Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
MIME-Version: 1.0
References: <20200311123848.118638-1-shile.zhang@linux.alibaba.com>
 <20200401154217.GQ22681@dhcp22.suse.cz> <dfc0014a-9b85-5eeb-70ea-d622ccf5d988@redhat.com>
 <20200401160048.GU22681@dhcp22.suse.cz> <20200401160929.jwekhr24tb44odea@ca-dmjordan1.us.oracle.com>
 <20200401161243.GW22681@dhcp22.suse.cz> <20200401161810.xvqikca2x46yqrlx@ca-dmjordan1.us.oracle.com>
 <20200401162655.GX22681@dhcp22.suse.cz> <CA+CK2bCGpG6kBjkGd-QP06kNtwezj8mW13Jdvbxs6ExzRaJSpQ@mail.gmail.com>
 <20200401164654.GY22681@dhcp22.suse.cz>
In-Reply-To: <20200401164654.GY22681@dhcp22.suse.cz>
From:   Pavel Tatashin <pasha.tatashin@soleen.com>
Date:   Wed, 1 Apr 2020 12:51:56 -0400
Message-ID: <CA+CK2bCKxok9Ho2NJd0kWR=YCi+eQqyfv6fg1Je3Lmov9PqzwQ@mail.gmail.com>
Subject: Re: [PATCH v3] mm: fix tick timer stall during deferred page init
To:     Michal Hocko <mhocko@kernel.org>
Cc:     Daniel Jordan <daniel.m.jordan@oracle.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        David Hildenbrand <david@redhat.com>,
        Shile Zhang <shile.zhang@linux.alibaba.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Kirill Tkhai <ktkhai@virtuozzo.com>,
        linux-mm <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

> > I do not remember seeing any real failures, this was a theoretical
> > window. So, we could potentially simply remove these locks until we
> > see a real boot failure in some interrupt thread. The allocation has
> > to be rather large as well.
>
> Yes please! We are really great at over complicating and over
> engineering stuff based on theoretical issues and build on top of that
> and make the code even more complex because nobody dares to re-evaluate
> and so on.

I will submit a patch (or revert) whichever is cleaner.

Pasha