diff mbox series

[11/12] xen: Expect xenstore write to fail when restricted

Message ID 1520535787-6223-12-git-send-email-ian.jackson@eu.citrix.com
State New
Headers show
Series [01/12] checkpatch: Add xendevicemodel_handle to the list of types | expand

Commit Message

Ian Jackson March 8, 2018, 7:03 p.m. UTC 
From: Ross Lagerwall <ross.lagerwall@citrix.com>

Saving the current state to xenstore may fail when running restricted
(in particular, after a migration). Therefore, don't report the error or
exit when running restricted.  Toolstacks that want to allow running
QEMU restricted should instead make use of QMP events to listen for
state changes.

CC: Ian Jackson <ian.jackson@eu.citrix.com>
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Ian Jackson <ian.jackson@eu.citrix.com>

---
v6: New patch in this version of the series
---
 hw/xen/xen-common.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

Comments

Anthony PERARD March 9, 2018, 3:46 p.m. UTC | #1 
On Thu, Mar 08, 2018 at 07:03:06PM +0000, Ian Jackson wrote:
> From: Ross Lagerwall <ross.lagerwall@citrix.com>
> 
> Saving the current state to xenstore may fail when running restricted
> (in particular, after a migration). Therefore, don't report the error or
> exit when running restricted.  Toolstacks that want to allow running
> QEMU restricted should instead make use of QMP events to listen for
> state changes.
> 
> CC: Ian Jackson <ian.jackson@eu.citrix.com>
> Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
> Reviewed-by: Ian Jackson <ian.jackson@eu.citrix.com>

Acked-by: Anthony PERARD <anthony.perard@citrix.com>

Thanks,
diff mbox series

Patch

diff --git a/hw/xen/xen-common.c b/hw/xen/xen-common.c
index f73b416..8ede246 100644
--- a/hw/xen/xen-common.c
+++ b/hw/xen/xen-common.c
@@ -101,7 +101,12 @@  static void xenstore_record_dm_state(struct xs_handle *xs, const char *state)
     }
 
     snprintf(path, sizeof (path), "device-model/%u/state", xen_domid);
-    if (!xs_write(xs, XBT_NULL, path, state, strlen(state))) {
+    /*
+     * This call may fail when running restricted so don't make it fatal in
+     * that case. Toolstacks should instead use QMP to listen for state changes.
+     */
+    if (!xs_write(xs, XBT_NULL, path, state, strlen(state)) &&
+            !xen_domid_restrict) {
         error_report("error recording dm state");
         exit(1);
     }