Mismerge at r330897 in stable/11, Audit report

[Rodney W. Grimes]

> On Wed, Mar 28, 2018 at 07:49:06PM -0700, Rodney W. Grimes wrote:
> > > On Wed, Mar 28, 2018 at 07:17:20PM -0700, Eitan Adler wrote:
> > > > On 28 March 2018 at 19:04, Rodney W. Grimes
> > > > <freebsd at pdx.rh.cn85.dnsmgr.net> wrote:
> > > > >> On 28 March 2018 at 18:35, Rodney W. Grimes
> > > > >> <freebsd at pdx.rh.cn85.dnsmgr.net> wrote:
> > > > >> >> >> Hi!
> > > > >> >> >>
> > > > >> >> >> This part of the MFC is wrong:
> > > > >> >> >>
> > > > >> >> >> https://svnweb.freebsd.org/base/stable/11/sys/sys/random.h?limit_changes=0&r1=330897&r2=330896&pathrev=330897
> > > > >> >
> > > > >> > Can we try to identify exactly what rXXXXXX that is a merge of?
> > > > >> >
> > > > >> >> >> Could you please MFC back the other random related changes too? Some
> > > > >> >> >> of them made by cem at .
> > > > >> >> >>
> > > > >> >> >> On 3/14/18, Eitan Adler <eadler at freebsd.org> wrote:
> > > > >> >> >>> Author: eadler
> > > > >> >> >>> Date: Wed Mar 14 03:19:51 2018
> > > > >> >> >>> New Revision: 330897
> > > > >> >> >>> URL: https://svnweb.freebsd.org/changeset/base/330897
> > > > >> >> >>>
> > > > >> >> >>> Log:
> > > > >> >> >>>   Partial merge of the SPDX changes
> > > > >> >> >>>
> > > > >> >> >>>   These changes are incomplete but are making it difficult
> > > > >> >> >>>   to determine what other changes can/should be merged.
> > > > >> >> >>>
> > > > >> >> >>>   No objections from:        pfg
> > > > >> >> >>>
> > > > >> >> > Am I missing something? If this MFC was supposed to be of the SPDX
> > > > >> >> > license tagging, why does it have any functional changes?
> > > > >> >> >
> > > > >> >> > Especially changes to random(4)?
> > > > >> >>
> > > > >> >> This was my failure. I only spot checked & compile-checked the diff
> > > > >> >> since I expected all changes to be comments/SPDX.
> > > > >> >>
> > > > >> >> However, I must have gotten carried away and included a few too many
> > > > >> >> revisions. Unfortunately some people have already merged fixes to my
> > > > >> >> failure and thus this can't be reverted as is without also reverting
> > > > >> >> those fixes.
> > > > >> >>
> > > > >> >> That said, I should do that since this commit message is utterly wrong.
> > > > >> >
> > > > >> > We do not have to revert r330897, with what follows I think
> > > > >> > we can easily find the revisions to revert from stable/11.
> > > > >> > ...
> > > > >>
> > > > >> While we don't have to revert it I'd rather do so than have bogus history.
> > > > >
> > > > > Reverting wont remove that history, thats a one way deal,
> > > > > and I think if we revert the bogus merges with the wrong
> > > > > history thats as good as its gona get.
> > > > >
> > > > >>
> > > > >> >From a look it seems the following was also merged:
> > > > >> r316370, r317095, r324394, and a few others.
> > > > >>
> > > > >> Is there a reason you don't want me to revert the changes?
> > > > >
> > > > > Repository churn is my main concern.
> > > > >
> > > > > It touches 6000+ files some of which have probably
> > > > > been touched since.   A very carefull pre commit
> > > > > audit would need to be done.
> > > > >
> > > > > Then another commit to 6000+ files to put it back,
> > > > > also needing a pre-commit audit. (Pretty easy now
> > > > > that I have a filter.)
> > > > 
> > > > I'm actually using the same filter you pasted above to verify that my
> > > > changes are only reverting said files. That said, while I'd prefer to
> > > > revert, I'll defer to others if they have a differing opinion.
> > > > 
> > > > 
> > > > Note that I won't have access my dev box after tomorrow for about a week.
> > > > 
> > > 
> > > IMHO, if you are going to be away for over a week while we're headed
> > > directly into the 11.2 release cycle, revert the change.  What you
> > > committed is not what was intended, clearly, and the commit message does
> > > not reflect what had happened (as you noted).
> > > 
> > > Any disagreements on this decision should be directed to me specifically
> > > in this case.
> > 
> > Glen,
> > 	I would rather not revert, as I believe that would cause more
> > damages as people have already cleaned up some of the mis merge from
> > this commit.  I am pretty sure a revert would lead to a broken tree.
> > 
> > In Eitans absence I am willing to take responsiblity to untangle
> > the wrong bits and clean up stable/11.
> > 
> > Ok?
> > 
> 
> I disagree with this approach.  A mishandled merge which as in this case
> contains extraneous changes limit our ability to properly audit the
> branch.
> 
> My strong feeling is that if "too many" revisions were merged, we should
> not piecemeal break out what should not have been included.  We should,
> instead, revert the offending commit as an "oops", redo the intended
> merge, and then in a separate commit re-apply the bits from the
> offending merge in a completely separate commit.
> 
> While this may be perceived as churn against the tree, it keeps tracking
> what happened much easier to manage, especially if we were to have to
> rely on mergeinfo.

And now already reverted, so moot.

> > Eitan,
> > 	Are you ok with that as well?

Eitan,
	I think the re merge of SPDX can wait tell you get back,
	you have the list of revisions already, and I am more
	than willing to audit your diff pre commit.

Thanks,

-- 
Rod Grimes                                                 rgrimes at freebsd.org