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Date:   Wed, 26 Jun 2019 10:15:16 +0200
From:   Oscar Salvador <osalvador@suse.de>
To:     David Hildenbrand <david@redhat.com>
Cc:     akpm@linux-foundation.org, mhocko@suse.com,
        dan.j.williams@intel.com, pasha.tatashin@soleen.com,
        Jonathan.Cameron@huawei.com, anshuman.khandual@arm.com,
        vbabka@suse.cz, linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 0/5] Allocate memmap from hotadded memory
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On Wed, Jun 26, 2019 at 10:11:06AM +0200, David Hildenbrand wrote:
> Back then, I already mentioned that we might have some users that
> remove_memory() they never added in a granularity it wasn't added. My
> concerns back then were never fully sorted out.
> 
> arch/powerpc/platforms/powernv/memtrace.c
> 
> - Will remove memory in memory block size chunks it never added
> - What if that memory resides on a DIMM added via MHP_MEMMAP_DEVICE?
> 
> Will it at least bail out? Or simply break?
> 
> IOW: I am not yet 100% convinced that MHP_MEMMAP_DEVICE is save to be
> introduced.

Uhm, I will take a closer look and see if I can clear your concerns.
TBH, I did not try to use arch/powerpc/platforms/powernv/memtrace.c
yet.

I will get back to you once I tried it out.

-- 
Oscar Salvador
SUSE L3