On Tue, Jun 4, 2019 at 5:18 AM Ilya Dryomov <idryomov@xxxxxxxxx> wrote: > > On Mon, Jun 3, 2019 at 10:23 PM Gregory Farnum <gfarnum@xxxxxxxxxx> wrote: > > > > On Mon, Jun 3, 2019 at 1:07 PM Ilya Dryomov <idryomov@xxxxxxxxx> wrote: > > > Can we also discuss how useful is allowing to recover a mount after it > > > has been blacklisted? After we fail everything with EIO and throw out > > > all dirty state, how many applications would continue working without > > > some kind of restart? And if you are restarting your application, why > > > not get a new mount? > > > > > > IOW what is the use case for introducing a new debugfs knob that isn't > > > that much different from umount+mount? > > > > People don't like it when their filesystem refuses to umount, which is > > what happens when the kernel client can't reconnect to the MDS right > > now. I'm not sure there's a practical way to deal with that besides > > some kind of computer admin intervention. (Even if you umount -l, that > > by design doesn't reply to syscalls and let the applications exit.) > > Well, that is what I'm saying: if an admin intervention is required > anyway, then why not make it be umount+mount? That is certainly more > intuitive than an obscure write-only file in debugfs... > I think 'umount -f' + 'mount -o remount' is better than the debugfs file > We have umount -f, which is there for tearing down a mount that is > unresponsive. It should be able to deal with a blacklisted mount, if > it can't it's probably a bug. > > Thanks, > > Ilya
