[Qemu-devel] [PATCH 7/7] spapr: Perform machine reset in a more sensible order

[David Gibson <david@gibson.dropbear.id.au>]

We've made several changes in the past to the machine reset order to fix
specific problems.  However, we've ended up with an order that doesn't make
a lot of logical sense.  This is an attempt to rectify this.

First we reset global CAS options, since that should depend on nothing
else.  Then we reset the CPUs, which shouldn't depend on external devices.
Then the irq subsystem, then the bulk of devices (which might rely on
irqs).  Finally we set up the entry state ready for boot, which could
potentially rely on a bunch of other things.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
 hw/ppc/spapr.c | 47 +++++++++++++++++++++++++----------------------
 1 file changed, 25 insertions(+), 22 deletions(-)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 5a919a6cc1..1560a11738 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -1724,6 +1724,28 @@ static void spapr_machine_reset(MachineState *machine)
     void *fdt;
     int rc;
 
+    /*
+     * If this reset wasn't generated by CAS, we should reset our
+     * negotiated options and start from scratch
+     */
+    if (!spapr->cas_reboot) {
+        spapr_ovec_cleanup(spapr->ov5_cas);
+        spapr->ov5_cas = spapr_ovec_new();
+
+        ppc_set_compat_all(spapr->max_compat_pvr, &error_fatal);
+    }
+
+    /*
+     * There is no CAS under qtest. Simulate one to please the code that
+     * depends on spapr->ov5_cas. This is especially needed to test device
+     * unplug, so we do that before resetting the DRCs.
+     */
+    if (qtest_enabled()) {
+        spapr_ovec_cleanup(spapr->ov5_cas);
+        spapr->ov5_cas = spapr_ovec_clone(spapr->ov5);
+    }
+
+    /* Reset the CPUs */
     spapr_caps_apply(spapr);
 
     first_ppc_cpu = POWERPC_CPU(first_cpu);
@@ -1741,34 +1763,15 @@ static void spapr_machine_reset(MachineState *machine)
         spapr_setup_hpt_and_vrma(spapr);
     }
 
-    qemu_devices_reset();
-
-    /*
-     * If this reset wasn't generated by CAS, we should reset our
-     * negotiated options and start from scratch
-     */
-    if (!spapr->cas_reboot) {
-        spapr_ovec_cleanup(spapr->ov5_cas);
-        spapr->ov5_cas = spapr_ovec_new();
-
-        ppc_set_compat_all(spapr->max_compat_pvr, &error_fatal);
-    }
-
+    /* Reset IRQ subsystem */
     /*
      * This is fixing some of the default configuration of the XIVE
      * devices. To be called after the reset of the machine devices.
      */
     spapr_irq_reset(spapr, &error_fatal);
 
-    /*
-     * There is no CAS under qtest. Simulate one to please the code that
-     * depends on spapr->ov5_cas. This is especially needed to test device
-     * unplug, so we do that before resetting the DRCs.
-     */
-    if (qtest_enabled()) {
-        spapr_ovec_cleanup(spapr->ov5_cas);
-        spapr->ov5_cas = spapr_ovec_clone(spapr->ov5);
-    }
+    /* Reset other devices */
+    qemu_devices_reset();
 
     /* DRC reset may cause a device to be unplugged. This will cause troubles
      * if this device is used by another device (eg, a running vhost backend
-- 
2.21.0