linux-kernel - Re: flush_dcache_page vs kunmap

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: <YYQowGK3oIAA5Yei@casper.infradead.org>
Date:   Thu, 4 Nov 2021 18:38:56 +0000
From:   Matthew Wilcox <willy@...radead.org>
To:     Linus Torvalds <torvalds@...ux-foundation.org>
Cc:     Christoph Hellwig <hch@....de>,
        linux-arch <linux-arch@...r.kernel.org>,
        Ira Weiny <ira.weiny@...el.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Thomas Gleixner <tglx@...utronix.de>
Subject: Re: flush_dcache_page vs kunmap_local

On Thu, Nov 04, 2021 at 08:30:55AM -0700, Linus Torvalds wrote:
> Why did this come up? Do you actually have some hardware or situation
> that cares?

Oh, we're doing review of the XFS/iomap folio patches, which led to
looking at zero_user_segments(), and I realised that memzero_page()
was now functionally identical to zero_user().  And you'd been quite
specific about not having flush_dcache_page() in there, so ... I wondered
if you'd had a change of mind.