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: <ZInVmrJdLWxOEkeD@casper.infradead.org>
Date:   Wed, 14 Jun 2023 15:58:34 +0100
From:   Matthew Wilcox <willy@...radead.org>
To:     Peter Xu <peterx@...hat.com>
Cc:     linux-kernel@...r.kernel.org, linux-mm@...ck.org,
        Andrea Arcangeli <aarcange@...hat.com>,
        John Hubbard <jhubbard@...dia.com>,
        Mike Rapoport <rppt@...nel.org>,
        David Hildenbrand <david@...hat.com>,
        Vlastimil Babka <vbabka@...e.cz>,
        "Kirill A . Shutemov" <kirill@...temov.name>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Mike Kravetz <mike.kravetz@...cle.com>,
        James Houghton <jthoughton@...gle.com>,
        Hugh Dickins <hughd@...gle.com>
Subject: Re: [PATCH 6/7] mm/gup: Accelerate thp gup even for "pages != NULL"

On Tue, Jun 13, 2023 at 05:53:45PM -0400, Peter Xu wrote:
> +			if (page_increm > 1)
> +				WARN_ON_ONCE(
> +				    try_grab_folio(compound_head(page),

You don't need to call compound_head() here; try_grab_folio() works
on tail pages just fine.

> +						   page_increm - 1,
> +						   foll_flags) == NULL);
> +
> +			for (j = 0; j < page_increm; j++) {
> +				subpage = nth_page(page, j);
> +				pages[i+j] = subpage;
> +				flush_anon_page(vma, subpage, start + j * PAGE_SIZE);
> +				flush_dcache_page(subpage);

You're better off calling flush_dcache_folio() right at the end.

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ