[CRIU] [PATCH v2 3/3] mount: handle tracefs more gracefully

[Tycho Andersen]

On Thu, May 12, 2016 at 09:34:10PM +0300, Pavel Emelyanov wrote:
> On 05/12/2016 06:39 PM, Tycho Andersen wrote:
> > On Thu, May 12, 2016 at 05:22:18PM +0300, Pavel Emelyanov wrote:
> >>> +		if (new->fstype->code == FSTYPE__TRACEFS) {
> >>> +			pr_info("\tskipping tracefs mounted at %s\n", new->mountpoint + 1);
> >>> +			mnt_entry_free(new);
> >>> +			new = NULL;
> >>> +			goto end;
> >>> +		}
> >>> +
> >>>  		pr_info("\ttype %s source %s mnt_id %d s_dev %#x %s @ %s flags %#x options %s\n",
> >>>  				fsname, new->source,
> >>>  				new->mnt_id, new->s_dev, new->root, new->mountpoint,
> >>
> >> Why do we need to drop this entry? AFAIU this is only required to make
> >> restore skip mounting one and let 'mount -t debugfs' do the thing, right?
> >> If yes, then we should keep this entry parsed and skip one on restore.
> >> I would say -- the debugfs' -> parse callback should walk all tracefs'
> >> MI's and set mounted on them to true.
> > 
> > Hmm, actually I'm a little confused about this. Do you mean ->mount
> > here?
> 
> Yup. I wrote ->parse by mistake :(

The problem here is still that it's a bind mount for us, so debugfs'
->mount never gets called :(

Tycho

> > I don't think setting mounted=true on dump via ->parse will skip
> > it on restore.
> 
> Of course :)
> 
> -- Pavel