linux-kernel - Re: [PATCH v5 1/9] lib: zstd: Add zstd compatibility wrapper

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: <812F138F-FB74-447C-86FB-5179E128078D@fb.com>
Date:   Tue, 10 Nov 2020 20:38:33 +0000
From:   Nick Terrell <terrelln@...com>
To:     Christoph Hellwig <hch@...radead.org>
CC:     Chris Mason <clm@...com>, Nick Terrell <nickrterrell@...il.com>,
        "Herbert Xu" <herbert@...dor.apana.org.au>,
        "linux-crypto@...r.kernel.org" <linux-crypto@...r.kernel.org>,
        "linux-btrfs@...r.kernel.org" <linux-btrfs@...r.kernel.org>,
        "squashfs-devel@...ts.sourceforge.net" 
        <squashfs-devel@...ts.sourceforge.net>,
        "linux-f2fs-devel@...ts.sourceforge.net" 
        <linux-f2fs-devel@...ts.sourceforge.net>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        Kernel Team <Kernel-team@...com>, Petr Malat <oss@...at.biz>,
        Johannes Weiner <jweiner@...com>,
        Niket Agarwal <niketa@...com>, Yann Collet <cyan@...com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Subject: Re: [PATCH v5 1/9] lib: zstd: Add zstd compatibility wrapper



> On Nov 10, 2020, at 10:39 AM, Christoph Hellwig <hch@...radead.org> wrote:
> 
> On Mon, Nov 09, 2020 at 02:01:41PM -0500, Chris Mason wrote:
>> You do consistently ask for a shim layer, but you haven???t explained what
>> we gain by diverging from the documented and tested API of the upstream zstd
>> project.  It???s an important discussion given that we hope to regularly
>> update the kernel side as they make improvements in zstd.
> 
> An API that looks like every other kernel API, and doesn't cause endless
> amount of churn because someone decided they need a new API flavor of
> the day.  Btw, I'm not asking for a shim layer - that was the compromise
> we ended up with.

I will put up a version of the patch set with the shim layer. I will follow the
kernel style guide for the shim, which will involve function renaming. I will
prefix the functions with “zstd_” instead of “ZSTD_” to make it clear that
this is not the upstream zstd API, but rather a kernel wrapper (and be closer
to the style guide).

Other than renaming to follow the kernel style guide, I will keep the API as
similar as possible to the existing API, to minimize churn.

Please let me know if you have any particular requests for the shim that I
haven't mentioned, or if you would prefer something else. Alternatively, 
comment on the patches once I put them up. Expect them later this week
or weekend.

Best,
Nick

> If zstd folks can't maintain a sane code base maybe we should just drop
> this childish churning code base from the tree.