netdev - Re: [RESEND PATCH 0/7] Add FOLL_LONGTERM to GUP fast and use it

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]

Date:   Thu, 21 Mar 2019 01:40:49 -0700
From:   Ira Weiny <ira.weiny@...el.com>
To:     Andrew Morton <akpm@...ux-foundation.org>
Cc:     John Hubbard <jhubbard@...dia.com>, Michal Hocko <mhocko@...e.com>,
        "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Jason Gunthorpe <jgg@...pe.ca>,
        Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Paul Mackerras <paulus@...ba.org>,
        "David S. Miller" <davem@...emloft.net>,
        Martin Schwidefsky <schwidefsky@...ibm.com>,
        Heiko Carstens <heiko.carstens@...ibm.com>,
        Rich Felker <dalias@...c.org>,
        Yoshinori Sato <ysato@...rs.sourceforge.jp>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        Ralf Baechle <ralf@...ux-mips.org>,
        James Hogan <jhogan@...nel.org>, linux-mm@...ck.org,
        linux-kernel@...r.kernel.org, linux-mips@...r.kernel.org,
        linuxppc-dev@...ts.ozlabs.org, linux-s390@...r.kernel.org,
        linux-sh@...r.kernel.org, sparclinux@...r.kernel.org,
        linux-rdma@...r.kernel.org, netdev@...r.kernel.org,
        Dan Williams <dan.j.williams@...el.com>
Subject: Re: [RESEND PATCH 0/7] Add FOLL_LONGTERM to GUP fast and use it

On Tue, Mar 19, 2019 at 03:19:30PM -0700, Andrew Morton wrote:
> On Sun, 17 Mar 2019 11:34:31 -0700 ira.weiny@...el.com wrote:
> 
> > Resending after rebasing to the latest mm tree.
> > 
> > HFI1, qib, and mthca, use get_user_pages_fast() due to it performance
> > advantages.  These pages can be held for a significant time.  But
> > get_user_pages_fast() does not protect against mapping FS DAX pages.
> > 
> > Introduce FOLL_LONGTERM and use this flag in get_user_pages_fast() which
> > retains the performance while also adding the FS DAX checks.  XDP has also
> > shown interest in using this functionality.[1]
> > 
> > In addition we change get_user_pages() to use the new FOLL_LONGTERM flag and
> > remove the specialized get_user_pages_longterm call.
> 
> It would be helpful to include your response to Christoph's question
> (http://lkml.kernel.org/r/20190220180255.GA12020@iweiny-DESK2.sc.intel.com)
> in the changelog.  Because if one person was wondering about this,
> others will likely do so.
> 
> We have no record of acks or reviewed-by's.  At least one was missed
> (http://lkml.kernel.org/r/CAOg9mSTTcD-9bCSDfC0WRYqfVrNB4TwOzL0c4+6QXi-N_Y43Vw@mail.gmail.com),
> but that is very very partial.

That is my bad.  Sorry to Mike.  And I have added him.

> 
> This patchset is fairly DAX-centered, but Dan wasn't cc'ed!

Agreed, I'm new to changing things which affect this many sub-systems and I
struggled with who should be CC'ed (get_maintainer.pl returned a very large
list  :-(.

I fear I may have cc'ed too many people, and the wrong people apparently, so
that may be affecting the review...

So again my apologies.  I don't know if Dan is going to get a chance to put a
reviewed-by on them this week but I thought I would send this note to let you
know I'm not ignoring your feedback.  Just waiting a bit before resending to
hopefully get some more acks/reviewed bys.

Thanks,
Ira

> 
> So ho hum.  I'll scoop them up and shall make the above changes to the
> [1/n] changelog, but we still have some work to do.
>