From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Hildenbrand <david@redhat.com>
Subject: Re: [PATCH RFC] mm/madvise: introduce MADV_POPULATE to
 prefault/prealloc memory
Date: Sat, 20 Feb 2021 10:01:00 +0100
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To: Mike Kravetz <mike.kravetz@oracle.com>, Peter Xu <peterx@redhat.com>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>, Arnd Bergmann <arnd@arndb.de>, Michal Hocko <mhocko@suse.com>, Oscar Salvador <osalvador@suse.de>, Matthew Wilcox <willy@infradead.org>, Andrea Arcangeli <aarcange@redhat.com>, Minchan Kim <minchan@kernel.org>, Jann Horn <jannh@google.com>, Jason Gunthorpe <jgg@ziepe.ca>, Dave Hansen <dave.hansen@intel.com>, Hugh Dickins <hughd@google.com>, Rik van Riel <riel@surriel.com>, "Michael S . Tsirkin" <mst@redhat.com>, "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>, Vlastimil Babka <vbabka@suse.cz>, Richard Henderson <rth@twiddle.net>, Ivan Kokshaysky <ink@jurassic.park.msu.ru>, Matt Turner <mattst88@gmail.com>, Thomas Bogendoerfer <tsbogend@alpha.franken.d>

> Sorry, for jumping in late ... hugetlb keyword just hit my mail filters :)
> 

Sorry for not realizing to cc you before I sent out the man page update :)

> Yes, it is true that hugetlb reservations are not numa aware.  So, even if
> pages are reserved at mmap time one could still SIGBUS if a fault is
> restricted to a node with insufficient pages.
> 
> I looked into this some years ago, and there really is not a good way to
> make hugetlb reservations numa aware.  preallocation, or on demand
> populating as proposed here is a way around the issue.


Thanks for confirming, this makes a lot of sense to me now.


-- 
Thanks,

David / dhildenb