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Date:   Wed, 10 Apr 2019 14:28:14 +0200
From:   Oscar Salvador <osalvador@suse.de>
To:     David Hildenbrand <david@redhat.com>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Michal Hocko <mhocko@suse.com>,
        Pavel Tatashin <pasha.tatashin@soleen.com>,
        Wei Yang <richard.weiyang@gmail.com>, Qian Cai <cai@lca.pw>,
        Arun KS <arunks@codeaurora.org>,
        Mathieu Malaterre <malat@debian.org>
Subject: Re: [PATCH] mm/memory_hotplug: Drop memory device reference after
 find_memory_block()
Message-ID: <20190410122811.jqlusigqc2a22647@d104.suse.de>
References: <20190410101455.17338-1-david@redhat.com>
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On Wed, Apr 10, 2019 at 12:14:55PM +0200, David Hildenbrand wrote:
> While current node handling is probably terribly broken for memory block
> devices that span several nodes (only possible when added during boot,
> and something like that should be blocked completely), properly put the
> device reference we obtained via find_memory_block() to get the nid.

We even have nodes sharing sections, so tricky to "fix".
But I agree that the way memblocks are being handled now sucks big time.

> 
> Fixes: d0dc12e86b31 ("mm/memory_hotplug: optimize memory hotplug")
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Oscar Salvador <osalvador@suse.de>
> Cc: Michal Hocko <mhocko@suse.com>
> Cc: David Hildenbrand <david@redhat.com>
> Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
> Cc: Wei Yang <richard.weiyang@gmail.com>
> Cc: Qian Cai <cai@lca.pw>
> Cc: Arun KS <arunks@codeaurora.org>
> Cc: Mathieu Malaterre <malat@debian.org>
> Signed-off-by: David Hildenbrand <david@redhat.com>

Well spotted David ;-)

Reviewed-by: Oscar Salvador <osalvador@suse.de>

-- 
Oscar Salvador
SUSE L3