Merge remote-tracking branch 'remotes/aperard/tags/pull-xen-20190204' into staging

Xen queue

* xen-block, the Xen PV backend, now handles resize.
* configure cleanup.
* xen-bus fix.

# gpg: Signature made Mon 04 Feb 2019 11:16:13 GMT
# gpg:                using RSA key F80C006308E22CFD8A92E7980CF5572FD7FB55AF
# gpg:                issuer "anthony.perard@citrix.com"
# gpg: Good signature from "Anthony PERARD <anthony.perard@gmail.com>" [marginal]
# gpg:                 aka "Anthony PERARD <anthony.perard@citrix.com>" [marginal]
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 5379 2F71 024C 600F 778A  7161 D8D5 7199 DF83 42C8
#      Subkey fingerprint: F80C 0063 08E2 2CFD 8A92  E798 0CF5 572F D7FB 55AF

* remotes/aperard/tags/pull-xen-20190204:
  xen-block: handle resize callback
  xen: fix xen-bus state model to allow frontend re-connection
  configure: Don't add Xen's libs to LDFLAGS
  configure: xen: Stop build-testing for xc_domain_create

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 19 insertions, 13 deletions

diff --git a/hw/xen/xen-bus.c b/hw/xen/xen-bus.c
index 3aeccec69c..49a725e8c7 100644
--- a/hw/xen/xen-bus.c
+++ b/hw/xen/xen-bus.c
@@ -547,20 +547,15 @@ static void xen_device_backend_changed(void *opaque)
     }
 
     /*
-     * If a backend is still 'online' then its state should be cycled
-     * back round to InitWait in order for a new frontend instance to
-     * connect. This may happen when, for example, a frontend driver is
-     * re-installed or updated.
-     * If a backend is not 'online' then the device should be destroyed.
+     * If a backend is still 'online' then we should leave it alone but,
+     * if a backend is not 'online', then the device should be destroyed
+     * once the state is Closed.
      */
-    if (xendev->backend_online &&
-        xendev->backend_state == XenbusStateClosed) {
-        xen_device_backend_set_state(xendev, XenbusStateInitWait);
-    } else if (!xendev->backend_online &&
-               (xendev->backend_state == XenbusStateClosed ||
-                xendev->backend_state == XenbusStateInitialising ||
-                xendev->backend_state == XenbusStateInitWait ||
-                xendev->backend_state == XenbusStateUnknown)) {
+    if (!xendev->backend_online &&
+        (xendev->backend_state == XenbusStateClosed ||
+         xendev->backend_state == XenbusStateInitialising ||
+         xendev->backend_state == XenbusStateInitWait ||
+         xendev->backend_state == XenbusStateUnknown)) {
         Error *local_err = NULL;
 
         if (!xen_backend_try_device_destroy(xendev, &local_err)) {
@@ -715,6 +710,17 @@ static void xen_device_frontend_changed(void *opaque)
 
     xen_device_frontend_set_state(xendev, state);
 
+    if (state == XenbusStateInitialising &&
+        xendev->backend_state == XenbusStateClosed &&
+        xendev->backend_online) {
+        /*
+         * The frontend is re-initializing so switch back to
+         * InitWait.
+         */
+        xen_device_backend_set_state(xendev, XenbusStateInitWait);
+        return;
+    }
+
     if (xendev_class->frontend_changed) {
         Error *local_err = NULL;