[PATCH v3] doc: add known issue in intel VF guide

[Steve Yang]

Add a known issue: configuring VLAN filters from VF is unsupported
for i40e driver 2.17.15.

Signed-off-by: Steve Yang <stevex.yang at intel.com>
---
 doc/guides/nics/intel_vf.rst | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/doc/guides/nics/intel_vf.rst b/doc/guides/nics/intel_vf.rst
index 09e1eb7685..d582f831da 100644
--- a/doc/guides/nics/intel_vf.rst
+++ b/doc/guides/nics/intel_vf.rst
@@ -697,3 +697,10 @@ i40e: Vlan strip of VF
 ~~~~~~~~~~~~~~~~~~~~~~
 
 The VF vlan strip function is only supported in the i40e kernel driver >= 2.1.26.
+
+i40e: Vlan filtering of VF
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+For i40e driver 2.17.15, configuring VLAN filters from the DPDK VF is unsupported.
+When applying VLAN filters on the VF it must first be configured from the
+corresponding PF.
-- 
2.25.1