Re: [Ksummit-discuss] [PATCH] media: add a subsystem profile documentation

[Joe Perches <joe@perches.com>]

On Thu, 2019-09-26 at 08:53 -0700, Kees Cook wrote:
> On Thu, Sep 26, 2019 at 08:14:03AM -0700, Joe Perches wrote:
> > On Wed, 2019-09-25 at 11:40 -0700, Kees Cook wrote:
> > > Is "6" a safe lower bound here? I thought 12 was the way to go?
> > []
> > > $ git log | egrep 'Fixes: [a-f0-9]{1,40}' | col2 | awk '{print length }' | sort | uniq -c | sort -n | tail
> > >     238 8
> > >     300 7
> > >     330 14
> > >     344 6
> > >     352 11
> > >     408 40
> > >     425 10
> > >     735 16
> > >    1866 13
> > >   31446 12
> > > 
> > > Hmpf, 6 is pretty high up there...
> > 
> > Yes, but your grep then col2 isn't right.
> > You are counting all the 'Fixes: commit <foo>' output
> > as 6 because that's the length of 'commit'.
> 
> the [a-f0-9]{1,40} already excludes "commit".

No it doesn't as commit starts with c which matches [a-f0-9]{1,40}

Try your original egrep command line yourself.

Maybe use:

$ git log | egrep 'Fixes: [a-f0-9]{1,40}' | awk '{ if (length($2) == 6) { print $0;} }'

The first few matches are

    the commit referenced in Fixes: below replaced the call to
    Fixes: commit 18a992787896 ("ARM: ux500: move soc_id driver to drivers/soc")
    Fixes: commit 0580dde59438 ("ASoC: simple-card-utils: add asoc_simple_debug_info()")
    Since Fixes: 8c5421c016a4 ("perf pmu: Display pmu name when printing
    Fixes: commit 961fb3c206dc ("ASoC: rockchip: rk3399_gru_sound: don't select unnecessary Platform")

> > I also think the length of the hex commit value doesn't
> > matter much as it's got to be a specific single commit
> > SHA1 anyway, otherwise the commit id lookup will fail.
> 
> Fail enough. We do already have 6-digit SHA1 collisions, so it seemed
> like using more than 6 would be nicer? *shrug* I don't have a strong
> opinion. :)
> 
> > > > > @@ -1031,6 +1040,7 @@ MAINTAINER field selection options:
> > > >      --roles => show roles (status:subsystem, git-signer, list, etc...)
> > > >      --rolestats => show roles and statistics (commits/total_commits, %)
> > > >      --file-emails => add email addresses found in -f file (default: 0 (off))
> > > > +    --fixes => for patches, add signatures of commits with 'Fixes: <commit>' (default: 1 (on))
> > > 
> > > Should "Tested-by" and "Co-developed-by" get added to @signature_tags ?
> > 
> > All "<foo>-by:" signatures are added.
> 
> Ah, I'd missed where that happened. I do note that's only when
> git-all-signature-types is set, which is default 0. (/me goes to add
> this to his invocations...)
> 
> my $email_git_all_signature_types = 0;
> ...
>     if ($email_git_all_signature_types) {
>         $signature_pattern = "(.+?)[Bb][Yy]:";
>     } else {
>         $signature_pattern = "\(" . join("|", @signature_tags) . "\)";
>     }
> 
> > > @commit_authors is unused?
> > 
> > Yes, authors are already required to sign-off so
> > it's just duplicating already existing signatures.
> 
> Sure, it just seemed odd to populate it if it wasn't going to be used.

It's a generic function.