[PATCH v2 09/10] accel/kvm: Assert vCPU is created when calling kvm_dirty_ring_reap*()

[Igor Mammedov <imammedo@xxxxxxxxxx>]

From: Philippe Mathieu-Daudé <philmd@xxxxxxxxxx>

Previous commits made sure vCPUs are realized before accelerators
(such KVM) use them. Ensure that by asserting the vCPU is created,
no need to return.

For more context, see commit 56adee407fc ("kvm: dirty-ring: Fix race
with vcpu creation").

Signed-off-by: Philippe Mathieu-Daudé <philmd@xxxxxxxxxx>
Reviewed-by: Richard Henderson <richard.henderson@xxxxxxxxxx>
Signed-off-by: Igor Mammedov <imammedo@xxxxxxxxxx>
---
CC: kvm@xxxxxxxxxxxxxxx
CC: peterx@xxxxxxxxxx
---
 accel/kvm/kvm-all.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index c65b790433..cb56d120a9 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -831,13 +831,11 @@ static uint32_t kvm_dirty_ring_reap_one(KVMState *s, CPUState *cpu)
     uint32_t count = 0, fetch = cpu->kvm_fetch_index;
 
     /*
-     * It's possible that we race with vcpu creation code where the vcpu is
+     * It's not possible that we race with vcpu creation code where the vcpu is
      * put onto the vcpus list but not yet initialized the dirty ring
-     * structures.  If so, skip it.
+     * structures.
      */
-    if (!cpu->created) {
-        return 0;
-    }
+    assert(cpu->created);
 
     assert(dirty_gfns && ring_size);
     trace_kvm_dirty_ring_reap_vcpu(cpu->cpu_index);
-- 
2.43.0