Michael Brown 2afeec08ab xen-netback: Check for hotplug-status existence before watching ... The logic in connect() is currently written with the assumption that xenbus_watch_pathfmt() will return an error for a node that does not exist. This assumption is incorrect: xenstore does allow a watch to be registered for a nonexistent node (and will send notifications should the node be subsequently created). As of commit 1f2565780 ("xen-netback: remove 'hotplug-status' once it has served its purpose"), this leads to a failure when a domU transitions into XenbusStateConnected more than once. On the first domU transition into Connected state, the "hotplug-status" node will be deleted by the hotplug_status_changed() callback in dom0. On the second or subsequent domU transition into Connected state, the hotplug_status_changed() callback will therefore never be invoked, and so the backend will remain stuck in InitWait. This failure prevents scenarios such as reloading the xen-netfront module within a domU, or booting a domU via iPXE. There is unfortunately no way for the domU to work around this dom0 bug. Fix by explicitly checking for existence of the "hotplug-status" node, thereby creating the behaviour that was previously assumed to exist. Signed-off-by: Michael Brown <mbrown@fensystems.co.uk> Reviewed-by: Paul Durrant <paul@xen.org> Signed-off-by: David S. Miller <davem@davemloft.net>		2021-04-13 15:24:14 -07:00
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Makefile	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
common.h	skbuff: Add skb parameter to the ubuf zerocopy callback	2021-01-07 16:06:37 -08:00
hash.c	treewide: Use fallthrough pseudo-keyword	2020-08-23 17:36:59 -05:00
interface.c	xen/events: link interdomain events to associated xenbus device	2021-02-11 14:47:00 -08:00
netback.c	Merge git://git.kernel.org:/pub/scm/linux/kernel/git/netdev/net	2021-03-09 17:15:56 -08:00
rx.c	xen/netback: avoid race in xenvif_rx_ring_slots_available()	2021-02-04 10:54:37 -08:00
xenbus.c	xen-netback: Check for hotplug-status existence before watching	2021-04-13 15:24:14 -07:00