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Date:   Fri, 22 Mar 2019 09:22:35 +0100
From:   Michal Hocko <mhocko@kernel.org>
To:     Souptick Joarder <jrdr.linux@gmail.com>
Cc:     Qian Cai <cai@lca.pw>, Andrew Morton <akpm@linux-foundation.org>,
        osalvador@suse.de, anshuman.khandual@arm.com,
        Linux-MM <linux-mm@kvack.org>, linux-kernel@vger.kernel.org,
        stable@vger.kernel.org
Subject: Re: [RESEND PATCH] mm/hotplug: fix notification in offline error path
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On Fri 22-03-19 12:20:12, Souptick Joarder wrote:
> On Thu, Mar 21, 2019 at 2:13 AM Qian Cai <cai@lca.pw> wrote:
> >
> > When start_isolate_page_range() returned -EBUSY in __offline_pages(), it
> > calls memory_notify(MEM_CANCEL_OFFLINE, &arg) with an uninitialized
> > "arg". As the result, it triggers warnings below. Also, it is only
> > necessary to notify MEM_CANCEL_OFFLINE after MEM_GOING_OFFLINE.
> 
> For my clarification, if test_pages_in_a_zone() failed in  __offline_pages(),
> we have the similar scenario as well. If yes, do we need to capture it
> in change log ?

Yes this is the same situation. We can add a note that the same applies
to test_pages_in_a_zone failure path but I do not think it is strictly
necessary. Thanks for the note anyway.
-- 
Michal Hocko
SUSE Labs