linux-kernel - Re: [PATCH v2 03/40] mm/rmap: introduce and use hugetlb_add_file

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <ZYPAoq0mIje00j+U@casper.infradead.org>
Date: Thu, 21 Dec 2023 04:35:46 +0000
From: Matthew Wilcox <willy@...radead.org>
To: David Hildenbrand <david@...hat.com>
Cc: linux-kernel@...r.kernel.org, linux-mm@...ck.org,
	Andrew Morton <akpm@...ux-foundation.org>,
	Hugh Dickins <hughd@...gle.com>,
	Ryan Roberts <ryan.roberts@....com>,
	Yin Fengwei <fengwei.yin@...el.com>,
	Mike Kravetz <mike.kravetz@...cle.com>,
	Muchun Song <muchun.song@...ux.dev>, Peter Xu <peterx@...hat.com>
Subject: Re: [PATCH v2 03/40] mm/rmap: introduce and use
 hugetlb_add_file_rmap()

On Wed, Dec 20, 2023 at 11:44:27PM +0100, David Hildenbrand wrote:
> hugetlb rmap handling differs quite a lot from "ordinary" rmap code.
> For example, hugetlb currently only supports entire mappings, and treats
> any mapping as mapped using a single "logical PTE". Let's move it out
> of the way so we can overhaul our "ordinary" rmap.
> implementation/interface.
> 
> Right now we're using page_dup_file_rmap() in some cases where "ordinary"
> rmap code would have used page_add_file_rmap(). So let's introduce and
> use hugetlb_add_file_rmap() instead. We won't be adding a
> "hugetlb_dup_file_rmap()" functon for the fork() case, as it would be
> doing the same: "dup" is just an optimization for "add".
> 
> What remains is a single page_dup_file_rmap() call in fork() code.
> 
> Add sanity checks that we end up with the right folios in the right
> functions.
> 
> Reviewed-by: Yin Fengwei <fengwei.yin@...el.com>
> Reviewed-by: Ryan Roberts <ryan.roberts@....com>
> Signed-off-by: David Hildenbrand <david@...hat.com>

Reviewed-by: Matthew Wilcox (Oracle) <willy@...radead.org>