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Date:   Mon, 10 Sep 2018 16:19:46 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Pasha Tatashin <Pavel.Tatashin@microsoft.com>
Cc:     "zaslonko@linux.ibm.com" <zaslonko@linux.ibm.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Linux Memory Management List <linux-mm@kvack.org>,
        "osalvador@suse.de" <osalvador@suse.de>,
        "gerald.schaefer@de.ibm.com" <gerald.schaefer@de.ibm.com>
Subject: Re: [PATCH] memory_hotplug: fix the panic when memory end is not on
 the section boundary
Message-ID: <20180910141946.GJ10951@dhcp22.suse.cz>
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On Mon 10-09-18 14:11:45, Pavel Tatashin wrote:
> Hi Michal,
> 
> It is tricky, but probably can be done. Either change
> memmap_init_zone() or its caller to also cover the ends and starts of
> unaligned sections to initialize and reserve pages.
> 
> The same thing would also need to be done in deferred_init_memmap() to
> cover the deferred init case.

Well, I am not sure TBH. I have to think about that much more. Maybe it
would be much more simple to make sure that we will never add incomplete
memblocks and simply refuse them during the discovery. At least for now.
-- 
Michal Hocko
SUSE Labs