Re: [PATCH] dlm: don't set RSB_MASTER_UNCERTAIN on rsb with no master

From: Ameer Hamza

Date: Tue Nov 03 2026 - 04:31:40 EST


On Mon, Nov 02, 2026 at 05:22:54PM -0500, Alexander Aring wrote:
> Hi,
>
> On Mon, Nov 2, 2026 at 4:03 PM Ameer Hamza <ameer.hamza@xxxxxxxxxxx> wrote:
> >
> > On Mon, Nov 02, 2026 at 03:38:12PM -0500, Alexander Aring wrote:
> > > Hi,
> > >
> > > On Mon, Nov 2, 2026 at 3:03 PM Ameer Hamza <ameer.hamza@xxxxxxxxxxx> wrote:
> > > >
> > > > On Mon, Nov 02, 2026 at 02:49:04PM -0500, Alexander Aring wrote:
> > > > > question:
> > > > >
> > > > > how do you "pause" anything in DLM?
> > > >
> > > > The nodes are VMs, so I freeze the dir node from the QEMU monitor. It
> > > > stays a member but never answers the lookup, and after the cancel I
> > > > evict it through configfs. That is what happens on our HA systems when
> > > > the peer reboots without leaving the lockspace and a pending request
> > > > gets cancelled before the peer is evicted.
> > >
> > > Still, do you just randomly freeze it, or do you busy/poll wait on
> > > specific struct field changes?
> >
> > I don't poll anything. The peer is frozen before the request is made,
> > so the lookup to it can never complete. Then the request is cancelled,
> > the peer is evicted and the name is requested again, and it asserts
> > every time.
> >
>
> I see, do you use dlm_controld/corosync as cluster manager?
>
> I would assume at some point they should fence the frozen peer.

No, our HA manages the lockspace itself through the same configfs and
sysfs interface dlm_controld uses, with its own peer monitoring. The
peer does get evicted, but the monitoring first waits about a minute
in case it comes back, and the lockspace keeps running until then. The
requester cancels after 60 s, so the cancel can arrive before the
eviction.

Best Regards,
Ameer Hamza