kvm: avoid reentring kvm_flush_coalesced_mmio_buffer()
mmio callbacks invoked by kvm_flush_coalesced_mmio_buffer() may
themselves indirectly call kvm_flush_coalesced_mmio_buffer().
Prevent reentering the function by checking a flag that indicates
we're processing coalesced mmio requests.
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/kvm-all.c b/kvm-all.c
index e7faf5c..c09ddf7 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -64,6 +64,7 @@
int vmfd;
int coalesced_mmio;
struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;
+ bool coalesced_flush_in_progress;
int broken_set_mem_region;
int migration_log;
int vcpu_events;
@@ -876,6 +877,13 @@
void kvm_flush_coalesced_mmio_buffer(void)
{
KVMState *s = kvm_state;
+
+ if (s->coalesced_flush_in_progress) {
+ return;
+ }
+
+ s->coalesced_flush_in_progress = true;
+
if (s->coalesced_mmio_ring) {
struct kvm_coalesced_mmio_ring *ring = s->coalesced_mmio_ring;
while (ring->first != ring->last) {
@@ -888,6 +896,8 @@
ring->first = (ring->first + 1) % KVM_COALESCED_MMIO_MAX;
}
}
+
+ s->coalesced_flush_in_progress = false;
}
static void do_kvm_cpu_synchronize_state(void *_env)
