[Virtio-fs] [PATCH] virtiofsd: Show submounts

[Miklos Szeredi]

On Tue, Apr 28, 2020 at 9:15 PM Dr. David Alan Gilbert
<dgilbert at redhat.com> wrote:

> So our current sequence is:
>
>    (new namespace)
>  1)    if (mount(NULL, "/", NULL, MS_REC | MS_SLAVE, NULL) < 0) {
>  2)   if (mount("proc", "/proc", "proc",
>            ....
>  3)   if (mount(source, source, NULL, MS_BIND | MS_REC, NULL) < 0) {
>  4)  (chdir newroot, pivot, chdir oldroot)
>  5)   if (mount("", ".", "", MS_SLAVE | MS_REC, NULL) < 0) {
>  6)   if (umount2(".", MNT_DETACH) < 0) {
>
> So are you saying we need a:
>        if (mount(NULL, "/", NULL, MS_REC | MS_SHARED, NULL) < 0) {
>
>   and can this go straight after (1) ?

Or right before (3).   Important thing is that that new mount will
only receive propagation if the type of the mount at source (before
(3) is performed) is shared.

Thanks,
Miklos