> -----Original Message----- > From: Roger Pau Monné <roger....@citrix.com> > Sent: 09 December 2019 17:18 > To: Durrant, Paul <pdurr...@amazon.com> > Cc: linux-ker...@vger.kernel.org; xen-devel@lists.xenproject.org; Juergen > Gross <jgr...@suse.com>; Stefano Stabellini <sstabell...@kernel.org>; > Boris Ostrovsky <boris.ostrov...@oracle.com> > Subject: Re: [Xen-devel] [PATCH 2/4] xenbus: limit when state is forced to > closed > > On Mon, Dec 09, 2019 at 04:26:15PM +0000, Durrant, Paul wrote: > > > > If you want unbind to actually do a proper unplug then that's extra > work > > > and not really something I want to tackle (and re-bind would still > need to > > > be toolstack initiated as something would have to re-create the > xenstore > > > area). > > > > > > Why do you say the xenstore area would need to be recreated? > > > > > > Setting state to closed shouldn't cause any cleanup of the xenstore > > > area, as that should already happen for example when using pvgrub > > > since in that case grub itself disconnects and already causes a > > > transition to closed and a re-attachment afterwards by the guest > > > kernel. > > > > > > > For some reason, when I originally tested, the xenstore area > disappeared. I checked again and it did not this time. I just ended up > with a frontend stuck in state 5 (because it is the system disk and won't > go offline) trying to talk to a non-existent backend. Upon re-bind the > backend goes into state 5 (because it sees the 5 in the frontend) and > leaves the guest wedged. > > Likely blkfront should go back to init state, but anyway, that's not > something that needs fixing as part of this series. >
Ok, cool. I am wondering though whether we ought to suppress bind/unbind for drivers that don't whitelist themselves (through the new xenbus_driver flag that I'll add). It's somewhat misleading that the nodes are there but don't necessarily work. Paul _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
