linux-kernel - Re: [RFC V2 14/18] famfs_fuse: GET_DAXDEV message and daxdev

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: <CAJfpegv8Ta+w4CTb7gvYUTx3kka1-pxcWX_ik=17wteU9XBT1g@mail.gmail.com>
Date: Thu, 14 Aug 2025 20:25:23 +0200
From: Miklos Szeredi <miklos@...redi.hu>
To: "Darrick J. Wong" <djwong@...nel.org>
Cc: John Groves <John@...ves.net>, Dan Williams <dan.j.williams@...el.com>, 
	Bernd Schubert <bschubert@....com>, John Groves <jgroves@...ron.com>, Jonathan Corbet <corbet@....net>, 
	Vishal Verma <vishal.l.verma@...el.com>, Dave Jiang <dave.jiang@...el.com>, 
	Matthew Wilcox <willy@...radead.org>, Jan Kara <jack@...e.cz>, 
	Alexander Viro <viro@...iv.linux.org.uk>, Christian Brauner <brauner@...nel.org>, 
	Randy Dunlap <rdunlap@...radead.org>, Jeff Layton <jlayton@...nel.org>, 
	Kent Overstreet <kent.overstreet@...ux.dev>, linux-doc@...r.kernel.org, 
	linux-kernel@...r.kernel.org, nvdimm@...ts.linux.dev, 
	linux-cxl@...r.kernel.org, linux-fsdevel@...r.kernel.org, 
	Amir Goldstein <amir73il@...il.com>, Jonathan Cameron <Jonathan.Cameron@...wei.com>, 
	Stefan Hajnoczi <shajnocz@...hat.com>, Joanne Koong <joannelkoong@...il.com>, 
	Josef Bacik <josef@...icpanda.com>, Aravind Ramesh <arramesh@...ron.com>, 
	Ajay Joshi <ajayjoshi@...ron.com>
Subject: Re: [RFC V2 14/18] famfs_fuse: GET_DAXDEV message and daxdev_table

On Thu, 14 Aug 2025 at 19:19, Darrick J. Wong <djwong@...nel.org> wrote:
> What happens if you want to have a fuse server that hosts both famfs
> files /and/ backing files?  That'd be pretty crazy to mix both paths in
> one filesystem, but it's in theory possible, particularly if the famfs
> server wanted to export a pseudofile where everyone could find that
> shadow file?

Either FUSE_DEV_IOC_BACKING_OPEN detects what kind of object it has
been handed, or we add a flag that explicitly says this is a dax dev
or a block dev or a regular file.  I'd prefer the latter.

Thanks,
Miklos