[Qemu-devel] [PATCH 1/2] Vring: vring's listener's priority should higher than kvm

[Liu Ping Fan <qemulist@gmail.com>]

From: Liu Ping Fan <pingfank@linux.vnet.ibm.com>

Hosts threads which handle vring should have high MemoryListener priority
than kvm. For currently code, take the following scenario:
  kvm_region_add() run earlier before vhost_region_add(), then in guest,
vring's desc[i] can refer to addressX in the new region known by guest.
But vhost does not know this new region yet, and the vring handler will
fail.

Signed-off-by: Liu Ping Fan <pingfank@linux.vnet.ibm.com>
---
 hw/virtio/dataplane/hostmem.c |    2 +-
 hw/virtio/vhost.c             |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/hw/virtio/dataplane/hostmem.c b/hw/virtio/dataplane/hostmem.c
index 37292ff..67cbce1 100644
--- a/hw/virtio/dataplane/hostmem.c
+++ b/hw/virtio/dataplane/hostmem.c
@@ -158,7 +158,7 @@ void hostmem_init(HostMem *hostmem)
         .eventfd_del = hostmem_listener_eventfd_dummy,
         .coalesced_mmio_add = hostmem_listener_coalesced_mmio_dummy,
         .coalesced_mmio_del = hostmem_listener_coalesced_mmio_dummy,
-        .priority = 10,
+        .priority = 9,
     };
 
     memory_listener_register(&hostmem->listener, &address_space_memory);
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index fbabf99..91c313b 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -856,7 +856,7 @@ int vhost_dev_init(struct vhost_dev *hdev, int devfd, const char *devpath,
         .log_global_stop = vhost_log_global_stop,
         .eventfd_add = vhost_eventfd_add,
         .eventfd_del = vhost_eventfd_del,
-        .priority = 10
+        .priority = 9
     };
     hdev->mem = g_malloc0(offsetof(struct vhost_memory, regions));
     hdev->n_mem_sections = 0;
-- 
1.7.4.4