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  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:   Wed, 15 Sep 2021 11:35:11 -0700
From:   Dan Williams <>
To:     Eric Sandeen <>
Cc:     linux-xfs <>,
        linux-ext4 <>,
        linux-fsdevel <>,
        Shiyang Ruan <>
Subject: Re: [PATCH 0/3 RFC] Remove DAX experimental warnings

On Wed, Sep 15, 2021 at 10:23 AM Eric Sandeen <> wrote:
> For six years now, when mounting xfs, ext4, or ext2 with dax, the drivers
> have logged "DAX enabled. Warning: EXPERIMENTAL, use at your own risk."
> IIRC, dchinner added this to the original XFS patchset, and Dan Williams
> followed suit for ext4 and ext2.
> After brief conversations with some ext4 and xfs developers and maintainers,
> it seems that it may be time to consider removing this warning.
> For XFS, we had been holding out for reflink+dax capability, but proposals
> which had seemed promising now appear to be indefinitely stalled, and
> I think we might want to consider that dax-without-reflink is no longer
> EXPERIMENTAL, while dax-with-reflink is simply an unimplemented future
> feature.

I do regret my gap in engagement since the last review as I got
distracted by CXL, but I've recently gotten my act together and picked
up the review again to help get Ruan's patches over the goal line [1].
I am currently awaiting Ruan's response to latest review feedback
(looks like a new posting this morning). During that review Christoph
identified some cleanups that would help Ruan's series, and those are
now merged upstream [2]. The last remaining stumbling block (further
block-device entanglements with dax-devices) I noted here [2]. The
proposal is to consider eliding device-mapper dax-reflink support for
now and proceed with just xfs-on-/dev/pmem until Mike, Jens, and
Christoph can chime in on the future of dax on block devices.

As far as I can see we have line of sight to land xfs-dax-reflink
support for v5.16, does anyone see that differently at this point?


Powered by blists - more mailing lists