On Donnerstag, 29. August 2019 18:27:30 CEST Greg Kurz wrote:
> > diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
> > index 586a6dccba..8cc65c2c67 100644
> > --- a/hw/9pfs/9p.c
> > +++ b/hw/9pfs/9p.c
> > @@ -572,10 +572,18 @@ static void coroutine_fn virtfs_reset(V9fsPDU *pdu)
> >
> > P9_STAT_MODE_SOCKET)
> >
> > /* This is the algorithm from ufs in spfs */
> >
> > -static void stat_to_qid(const struct stat *stbuf, V9fsQID *qidp)
> > +static int stat_to_qid(V9fsPDU *pdu, const struct stat *stbuf, V9fsQID
> > *qidp)>
> > {
> >
> > size_t size;
> >
> > + if (pdu->s->dev_id != stbuf->st_dev) {
> > + error_report_once(
> > + "9p: Multiple devices detected in same VirtFS export. "
> > + "You must use a separate export for each device."
> > + );
> > + return -ENODEV;
>
> As explained in the v5 review, we don't necessarily want to break existing
> cross-device setups that just happen to work. Moreover, the next patch
> re-allows them since remap_inodes=ignore is the default. I would thus
> only do:
>
> warn_report_once(
> "9p: Multiple devices detected in same VirtFS export, "
> "which might lead to file ID collisions and severe "
> "misbehaviours on guest! You should use a separate "
> "export for each device shared from host."
> );
>
> So I've just changed that and applied to 9p-next since it is
> a valuable improvement. Note that I've kept the signature change
> of stat_to_qid() for simplicity even if it isn't needed before
> the next patch.
I'm fine with your changes.
Dropping "return -ENODEV" in this patch was beyond my default level for
details since this is really just a very detailed sort of git history
tweaking. :) Like you already pointed out, not aborting (as default behaviour)
would have been addressed with the subsequent patch anyway.
