Re: [PATCH 0/2] fix http deadlock on giant ref negotiations

> On Wed, May 13, 2015 at 08:47:24PM -0400, Jeff King wrote:
> 
> > The fundamental problem is the deadlock on the server side, which is
> > producing bogus protocol output. And that's a mismatch between what
> > Apache expects (that the CGI will read all of the input request and then
> > generate an output request) and what the CGI wants to do (stream output
> > as it reads the input).
> 
> At first I was irritated with Apache for this. But thinking on it more,
> it's really due to our shoe-horning of a full-duplex protocol into the
> half-duplex HTTP protocol. Even if we could convince Apache to work in a
> full-duplex way here, and even if our client is full-duplex (since
> otherwise we are just trading pipe buffers for TCP buffers), we still
> may face arbitrary HTTP proxies or other infrastructure in the middle.
> 
> So here's a series to try to address the issue. The first patch is a
> fixed version of the die-recursion fixup I posted earlier. The second is
> the interesting one.
> 
>   [1/2]: http-backend: fix die recursion with custom handler
>   [2/2]: http-backend: spool ref negotiation requests to buffer
> 
> I have no clue how to write a test that would trigger this reliably
> without requiring a gigantic test fixture. However, I did confirm that
> it fixes the problem on the chromium case you provided (which otherwise
> deadlocks reliably for me).