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>
This commit is contained in:
Avi Kivity 2011-10-18 19:43:12 +02:00 committed by Marcelo Tosatti
parent 626c427624
commit 1cae88b9f4

View File

@ -64,6 +64,7 @@ struct KVMState
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 @@ static int kvm_handle_internal_error(CPUState *env, struct kvm_run *run)
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 @@ void kvm_flush_coalesced_mmio_buffer(void)
ring->first = (ring->first + 1) % KVM_COALESCED_MMIO_MAX;
}
}
s->coalesced_flush_in_progress = false;
}
static void do_kvm_cpu_synchronize_state(void *_env)