Yep. I do that with the powerpc tree sometimes, too: I'll ACK a
drivers/net change that is obviously PPC-specific, and that drivers/net
change will go in via paulus.
Like you said, it's done on a per-patch not git tree basis at the moment.
That sort of cooperation has become common: in areas of shared
responsibility, request an ack, and then the "most obvious" person
(generally the one with most merge dependencies) merges that
shared-responsibility change along with some other changes specific to
their own tree.
Jeff
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