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Date:   Tue, 27 Aug 2019 09:22:42 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Alastair D'Silva <alastair@d-silva.org>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Oscar Salvador <osalvador@suse.de>,
        Mike Rapoport <rppt@linux.ibm.com>,
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        David Hildenbrand <david@redhat.com>, Qian Cai <cai@lca.pw>,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] mm: don't hide potentially null memmap pointer in
 sparse_remove_section
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On Tue 27-08-19 17:00:16, Alastair D'Silva wrote:
[...]
> The NULL check was added in commit:
> 95a4774d055c ("memory-hotplug: update mce_bad_pages when removing the
> memory")
> where memmap was originally inited to NULL, and only conditionally
> given a value.
> 
> With this in mind, since that situation is no longer true, I think we
> could instead drop the NULL check.

This would be much more preferable to the original patch.

-- 
Michal Hocko
SUSE Labs