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: Thu, 18 Feb 2021 12:27:14 +0100
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To: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Vlastimil Babka <vbabka@suse.cz>, David Hildenbrand <david@redhat.com>, 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>, Richard Henderson <rth@twiddle.net>, Ivan Kokshaysky <ink@jurassic.park.msu.ru>, Matt Turner <mattst88@gmail.com>


> Am 18.02.2021 um 12:15 schrieb Rolf Eike Beer <eike-kernel@sf-tec.de>:
>=20
> =EF=BB=BF
>>=20
>>> Let's introduce MADV_POPULATE with the following semantics
>>> 1. MADV_POPULATED does not work on PROT_NONE and special VMAs. It works
>>>   on everything else.
>>> 2. Errors during MADV_POPULATED (especially OOM) are reported. If we hit=

>>>   hardware errors on pages, ignore them - nothing we really can or
>>>   should do.
>>> 3. On errors during MADV_POPULATED, some memory might have been
>>>   populated. Callers have to clean up if they care.
>>> 4. Concurrent changes to the virtual memory layour are tolerated - we
>                                                    ^t
>>>   process each and every PFN only once, though.
>>> 5. If MADV_POPULATE succeeds, all memory in the range can be accessed
>>>   without SIGBUS. (of course, not if user space changed mappings in the
>>>   meantime or KSM kicked in on anonymous memory).
>=20
> You are talking both about MADV_POPULATE and MADV_POPULATED here.
>=20

Already fixed up :) thanks!

> Eike
>=20