Re: [PATCH] init/do_mounts.c: Add root="fstag:<tag>" syntax for root device

[Dominique Martinet]

... And that's why I told Changbin Du a few times his patches needed
more Ccs :/

FWIW: we just got last month a couple of patches that would allow
initrd-less 9p root mount (using the nfs/cifs method described below
with root=/dev/v9fs)

Vivek Goyal wrote on Tue, Jun 08, 2021 at 11:35:24AM -0400:
> NFS and CIFS use "root=/dev/nfs" and CIFS passes "root=/dev/cifs" and
> actual root device details come from filesystem specific kernel
> command line options.
> 
> virtiofs does not seem to fit in any of the above categories. In fact
> we have 9pfs which can be used to boot from but it also does not
> have a proper syntax to specify rootfs and does not fit into any of
> the existing syntax. They both expect a device "tag" to be passed
> in a device to be mounted. And filesystem knows how to parse and
> use "tag".
> 
> So this patch proposes that we add a new prefix "fstag:" which specifies
> that identifier which follows is filesystem specific tag and its not
> a block device. Just pass this tag to filesystem and filesystem will
> figure out how to mount it.


...However I agree something more generic would be welcome in my
opinion, so I like this approach.

I'll give it a try for 9p over the weekend and report back.

-- 
Dominique