linux-kernel - Re: [PATCH 0/2] KVM: do not assume PTE is writable after follow

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: <20210209081951.GA1704636@infradead.org>
Date:   Tue, 9 Feb 2021 08:19:51 +0000
From:   Christoph Hellwig <hch@...radead.org>
To:     Jason Gunthorpe <jgg@...pe.ca>
Cc:     Peter Xu <peterx@...hat.com>, dan.j.williams@...el.com,
        Paolo Bonzini <pbonzini@...hat.com>,
        linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
        linux-mm@...ck.org, Andrew Morton <akpm@...ux-foundation.org>
Subject: Re: [PATCH 0/2] KVM: do not assume PTE is writable after follow_pfn

On Mon, Feb 08, 2021 at 07:26:25PM -0400, Jason Gunthorpe wrote:
> > > page_mkclean() has some technique to make the notifier have the right
> > > size without becoming entangled in the PTL locks..
> > 
> > Right.  I guess it's because dax doesn't have "struct page*" on the
> > back, so it
> 
> It doesn't? I thought DAX cases did?

File system DAX has a struct page, device DAX does not.  Which means
everything using iomap should have a page available, but i'm adding
Dan as he should know the details :)