On Fri, 6 Aug 2021 at 10:08, Amir Goldstein <amir73il@xxxxxxxxx> wrote: > > On Fri, Aug 6, 2021 at 10:52 AM Miklos Szeredi <miklos@xxxxxxxxxx> wrote: > > > > On Thu, 29 Jul 2021 at 07:27, Amir Goldstein <amir73il@xxxxxxxxx> wrote: > > > > > Given that today, subvolume mounts (or any mounts) on the lower layer > > > are not followed by overlayfs, I don't really see the difference > > > if mounts are created manually or automatically. > > > Miklos? > > > > Never tried overlay on btrfs. Subvolumes AFAIK do not use submounts > > currently, they are a sort of hack where the st_dev changes when > > crossing the subvolume boundary, but there's no sign of them in > > /proc/mounts (there's no d_automount in btrfs). > > That's what Niel's patch 11/11 is proposing to add and that's the reason > he was asking if this is going to break overlayfs over btrfs. > > My question was, regardless of btrfs, can ovl_lookup() treat automount > dentries gracefully as empty dirs or just read them as is, instead of > returning EREMOTE on lookup? > > The rationale is that we use a private mount and we are not following > across mounts from layers anyway, so what do we care about > auto or manual mounts? I guess that depends on the use cases. If no one cares (as is the case apparently), the simplest is to leave it the way it is. Thanks, Miklos