Re: [RFC PATCH net-next 2/2] net: dcb: add new apptrust attribute

Hi Daniel,

On Thu, Sep 08, 2022 at 02:04:42PM +0200, Daniel Machon wrote:

Add a new apptrust extension attribute to the 8021Qaz APP managed
object.

The new attribute is meant to allow drivers, whose hw supports the
notion of trust, to be able to set whether a particular app selector is
to be trusted - and also the order of precedence of selectors.

A new structure ieee_apptrust has been created, which contains an array
of selectors, where lower indexes has higher precedence.

Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
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Let's say I have a switch which only looks at VLAN PCP/DEI if the bridge
vlan_filtering setting is enabled (otherwise, the switch is completely
VLAN unaware, including for QoS purposes).

Would it be ok to report through ieee_getapptrust() that the PCP
selector is trusted when under a vlan_filtering bridge, not trusted when
not under a vlan_filtering bridge, and deny changes to ieee_setapptrust()
for the PCP selector? I see the return value is not cached anywhere
within the kernel, just passed to the user.