[dpdk-dev] [PATCH v2] doc: add virtio lsc note

[Zhiyong Yang]

Virtio PMD has already supported link status change(lsc), but VM which
must be created by qemu 2.7.0 and above can support it when vhost
user disconnects, since the capability to detect vhost user disconnection
is introduced in qemu 2.7.0. The patch updates doc to let user know that.

Signed-off-by: Zhiyong Yang <zhiyong.yang at intel.com>
---

Changes in v2:
reword the doc and commit log.

 doc/guides/nics/virtio.rst | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/doc/guides/nics/virtio.rst b/doc/guides/nics/virtio.rst
index 4d6a83768..abf42dff5 100644
--- a/doc/guides/nics/virtio.rst
+++ b/doc/guides/nics/virtio.rst
@@ -291,6 +291,11 @@ interrupt, Rx interrupts, and Tx interrupts. Config interrupt is used for
 notification of device configuration changes, especially link status (lsc).
 Interrupt mode is translated into Rx interrupts in the context of DPDK.
 
+.. Note:: Virtio PMD has already supported to receive lsc from qemu when link
+status changes, especially when vhost user disconnects, but it fails to do that if VM
+is created by qemu 2.6.2 or below, since the capability to detect vhost user
+disconnection is introduced in qemu 2.7.0.
+
 Prerequisites for Rx interrupts
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-- 
2.13.3