Hi, > -----Original Message----- > From: Maayan Kashani <[email protected]> > Sent: Thursday, July 30, 2026 11:45 PM > To: [email protected] > Cc: Maayan Kashani <[email protected]>; Raslan Darawsheh > <[email protected]>; Dariusz Sosnowski <[email protected]>; Slava > Ovsiienko <[email protected]>; Bing Zhao <[email protected]>; Ori Kam > <[email protected]>; Suanming Mou <[email protected]>; Matan Azrad > <[email protected]> > Subject: [PATCH] doc/mlx5: document modify field limitation on group 0 > > Document that on the root table, two sequential MODIFY_FIELD actions where > the second uses a field modified by the first as src are not > supported: the second action is handled before the first change is > applied. Only immediate src types (VALUE/POINTER) are allowed on group 0 > for sync HWS non-template and DV flows. > > Signed-off-by: Maayan Kashani <[email protected]> > --- > doc/guides/nics/mlx5.rst | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/doc/guides/nics/mlx5.rst b/doc/guides/nics/mlx5.rst index > 9b035b878e0..aa751669444 100644 > --- a/doc/guides/nics/mlx5.rst > +++ b/doc/guides/nics/mlx5.rst > @@ -3425,6 +3425,12 @@ Limitations > > #. In template tables of group 0, the modify action must be fully masked. > > +#. On group 0 (root table), when using sync API, two sequential > + ``RTE_FLOW_ACTION_TYPE_MODIFY_FIELD`` actions where the first modifies > a > + packet or metadata field and the second uses that field as ``src`` are > not > + supported. On the root table the second action is handled before the > first > + change is applied, so the source still reads the original field value. > + > #. Modification of an arbitrary place in a packet via > the special ``RTE_FLOW_FIELD_START`` field ID is not supported. > > -- > 2.21.0
Acked-by: Bing Zhao <[email protected]>
