In the parts of the Kernel I work with, reviews are usually given by a plain
tag. I think this is not enough to keep a good code quality, so I'll start with
my theses first:

1) we need a better distinction between Acked-by: and Reviewed-by: and encourage
   stricter use of that

2) Reviewed-by should have a description of the review done (and the review not
   done)

3) trivial patches should rather get Acked-by

4) failing the above should be constructively criticized


Some more words about each item:

1) I am definitely not striving for a clear line, that's impossible. Yet, from
what I experience, the overlap between the two became large. It reduces the
extra value a Reviewed-by should have.

2) A short paragraph will usually do. Of course, trust helps a lot, but it
doesn't solve everything. Trusted people can be in a hurry, too, etc. And for
people I don't know, the plain tag doesn't tell me much. Examples for short
descriptions: "I can't say much about the media part, but the I2C part is
proper" or "I also checked the documentation and I think this is a good
approach to overcome the issue" or "All my concerns in the preceding
discussions have been addressed"

3) Again, no hard line on what is trivial can be made. Still, I think it will
add to the extra value of a review tag if it is only applied to something which
is non-trivial, so we should try to have a better distinction.

4) We are in such a need for people reviewing that it can be challenging for
maintainers to be picky about reviews (you can partly include me here). A
kernel-wide movement aiming for a better distinction between ack (= looks good)
and review helps both maintainers and developers, I think.

These things will hopefully help me as a maintainer to better evaluate trust
for a patch based on the tags given. So, I will try that in the I2C subsystem.
I would prefer, though, not to be an island but to have something which is
accepted kernel-wide.

Disclaimer: I am mainly active in the drivers section of Linux. If reviews are
handled differently in other parts, I am all ears.

Well, I am all ears, anyhow. Opinions?

Kind regards,

  Wolfram