[PATCH v8 6/7] spapr: use DEVICE_UNPLUG_GUEST_ERROR to report unplug errors

[Daniel Henrique Barboza <danielhb413@gmail.com>]

Linux Kernel 5.12 is now unisolating CPU DRCs in the device_removal
error path, signalling that the hotunplug process wasn't successful.
This allow us to send a DEVICE_UNPLUG_GUEST_ERROR in drc_unisolate_logical()
to signal this error to the management layer.

We also have another error path in spapr_memory_unplug_rollback() for
configured LMB DRCs. Kernels older than 5.13 will not unisolate the LMBs
in the hotunplug error path, but it will reconfigure them. Let's send
the DEVICE_UNPLUG_GUEST_ERROR event in that code path as well to cover the
case of older kernels.

Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
---
 hw/ppc/spapr.c     | 10 +++++++++-
 hw/ppc/spapr_drc.c |  9 +++++----
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 4f1ee90e9e..206c536d3a 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -29,6 +29,7 @@
 #include "qemu/datadir.h"
 #include "qapi/error.h"
 #include "qapi/qapi-events-machine.h"
+#include "qapi/qapi-events-qdev.h"
 #include "qapi/visitor.h"
 #include "sysemu/sysemu.h"
 #include "sysemu/hostmem.h"
@@ -3686,11 +3687,18 @@ void spapr_memory_unplug_rollback(SpaprMachineState *spapr, DeviceState *dev)
 
     /*
      * Tell QAPI that something happened and the memory
-     * hotunplug wasn't successful.
+     * hotunplug wasn't successful. Keep sending
+     * MEM_UNPLUG_ERROR even while sending
+     * DEVICE_UNPLUG_GUEST_ERROR until the deprecation of
+     * MEM_UNPLUG_ERROR is due.
      */
     qapi_error = g_strdup_printf("Memory hotunplug rejected by the guest "
                                  "for device %s", dev->id);
+
     qapi_event_send_mem_unplug_error(dev->id ? : "", qapi_error);
+
+    qapi_event_send_device_unplug_guest_error(!!dev->id, dev->id,
+                                              dev->canonical_path);
 }
 
 /* Callback to be called during DRC release. */
diff --git a/hw/ppc/spapr_drc.c b/hw/ppc/spapr_drc.c
index a4d9496f76..f8ac0a10df 100644
--- a/hw/ppc/spapr_drc.c
+++ b/hw/ppc/spapr_drc.c
@@ -17,6 +17,8 @@
 #include "hw/ppc/spapr_drc.h"
 #include "qom/object.h"
 #include "migration/vmstate.h"
+#include "qapi/error.h"
+#include "qapi/qapi-events-qdev.h"
 #include "qapi/visitor.h"
 #include "qemu/error-report.h"
 #include "hw/ppc/spapr.h" /* for RTAS return codes */
@@ -173,10 +175,9 @@ static uint32_t drc_unisolate_logical(SpaprDrc *drc)
                              "for device %s", drc->dev->id);
             }
 
-            /*
-             * TODO: send a QAPI DEVICE_UNPLUG_ERROR event when
-             * it is implemented.
-             */
+            qapi_event_send_device_unplug_guest_error(!!drc->dev->id,
+                                                      drc->dev->id,
+                                                      drc->dev->canonical_path);
         }
 
         return RTAS_OUT_SUCCESS; /* Nothing to do */
-- 
2.31.1