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Subject: Re: [Cake] [PATCH net] sch_cake: Interpret fwmark parameter as a
	bitmask
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From: Toke H=F8iland-J=F8rgensen <toke@redhat.com>
Date: Thu, 14 Mar 2019 23:08:22 +0100

> We initially interpreted the fwmark parameter as a flag that simply t=
urned
> on the feature, using the whole skb->mark field as the index into the=
 CAKE
> tin_order array. However, it is quite common for different applicatio=
ns to
> use different parts of the mask field for their own purposes, each us=
ing a
> different mask.
> =

> Support this use of subsets of the mark by interpreting the TCA_CAKE_=
FWMARK
> parameter as a bitmask to apply to the fwmark field when reading it. =
The
> result will be right-shifted by the number of unset lower bits of the=
 mask
> before looking up the tin.
> =

> In the original commit message we also failed to credit Felix Resch w=
ith
> originally suggesting the fwmark feature back in 2017; so the Suggest=
ed-By
> in this commit covers the whole fwmark feature.
> =

> Fixes: 0b5c7efdfc6e ("sch_cake: Permit use of connmarks as tin classi=
fiers")
> Suggested-by: Felix Resch <fuller@beif.de>
> Signed-off-by: Toke H=F8iland-J=F8rgensen <toke@redhat.com>

You are lucky you decided to do this before a released kernel had this =
UAPI
available.

Applied.