How to map voice packet to egress priority queue

Unanswered Question

Voice packet was marked with DSCP EF, switch port was set to "trust dscp".

As I known, most of Cisco switch and modules support only CoS maps to egress certain queue before sending out.

My question is:

if I only trust dscp at ingress port, the dscp value is reserved in the switch, how about CoS? The CoS will be generated based on the internal/reserved DSCP based on DSCP-CoS mapping, right? And then, use the new CoS to map queue, right? That is to say, new CoS must be generated and rewrited to packets together reserved DSCP before mapping to a egress queue, right?

For example, trust dscp(EF) only at ingress port, CoS 5 will be generated internal, DSCP/COS 46/5 will be rewrited to packet based on the DSCP-COS mapping, then switch used CoS(5) to map egress priority queue and send packet out. Is it correct?

Appreciated for your comments.

I have this problem too.
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