[vlc-devel] [PATCH 5/7] playlist: fix deadlock on destruction while preparser adds items to playlist

[Rémi Denis-Courmont]

Le keskiviikkona 29. maaliskuuta 2017, 21.12.27 EEST Filip Roséen a écrit :
> Hi Rémi,
> 
> On 2017-03-29 22:01, Rémi Denis-Courmont wrote:
> > Le keskiviikkona 29. maaliskuuta 2017, 20.45.59 EEST Filip Roséen a écrit 
:
> > > > > It fixes the issue described in ticket [#18151][1], which you closed
> > > > > as
> > > > > a
> > > > > duplicate of [#17652][2]. I would be interested to see know how
> > > > > #18151
> > > > > is
> > > > > not fixed, as I did extensive testing and a lot of proof-reading to
> > > > > inspect the relevant paths taken.
> > > > 
> > > > I would be interested to know how a lock inversion can be fixed while
> > > > not
> > > > settling for one lock order or the other, nor eliminating the code
> > > > paths
> > > > leading to either orders.
> > > 
> > > As stated, you are the one who closed `#18151` as a duplicate of
> > > `#17652`; the ticket description for the former in detail describe
> > > what lock is being taken, and why it deadlocks.
> > 
> > It is not strictly a duplicate but more of a specific instance of it. And
> > as ALREADY NOTED BEFORE, this is just removing one code path leading to
> > it.
> > 
> > I did warn Thomas that this was a playlist problem and not a preparser/
> > prefetcher problem quite a while back. If the whole point of this patch
> > series was to fix this bug, then it seems that you missed the point and
> > unfortunately wasted your time.
> 
> I do not believe that I have wasted my time, as such it has not been a
> waste of time (as what constitutes as "waste of time" is highly
> subjective); you are of course entitled to your own opinion.
> 
> Once again, I am very interested in knowledge related to how the
> issue described by `#18151` is reproducible after the relevant set of
> patches.

Given you insist on not explaining, I´m going to assume that this means that I 
am right and this is not fixing the bug.

18151 is a THEORETICAL bug. You fix it by giving a THEORETICAL PROOF that it 
is fixed, in other words, by enforcing a consistent lock order.

-- 
雷米‧德尼-库尔蒙
https://www.remlab.net/