[dpdk-dev] [PATCH] doc: add note for vhost builtin example

[Xuan Ding]

Add memory pre-allocation note for vhost example when enabling
"builtin-net-driver".

Signed-off-by: Xuan Ding <xuan.ding at intel.com>
---
 doc/guides/sample_app_ug/vhost.rst | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/doc/guides/sample_app_ug/vhost.rst b/doc/guides/sample_app_ug/vhost.rst
index a71ada654..1db3ae931 100644
--- a/doc/guides/sample_app_ug/vhost.rst
+++ b/doc/guides/sample_app_ug/vhost.rst
@@ -201,3 +201,9 @@ Common Issues
 
   QEMU vhost net device start will fail if protocol feature is not negotiated.
   DPDK virtio-user pmd can be the replacement of QEMU.
+
+* Device start fails when enabling "builtin-net-driver" without memory
+  pre-allocation
+
+  The builtin example doesn't support dynamic memory allocation. "--socket-mem"
+  option need to be added when enabling "builtin-net-driver".
-- 
2.17.1