Bug#335528: subversion: svn+ssh breaks will automatic ssh connection caching

[Vincent Lefevre]

On 2005-10-24 14:49:44 +0100, Paul Brook wrote:
> The combination of svn+ssh and automatic ssh connection caching is
> broken.
> 
> In my ~/.ssh/config I have 
> 
> ControlPath /tmp/.ssh-%h-%p-%r
> ControlMaster auto

You're not allowed to do that as the master connection will close
any slave connection. More precisely, the following behavior may
happen with a single svn command:

1. The subversion client does a first ssh connection.
   A master ssh connection is automatically opened.

2. The subversion client does a second ssh connection.
   A slave connection is opened.

3. The subversion client closes the first ssh connection.
   This closes the master *and* the slave connections.

So, svn fails. This is definitely not a Subversion bug here.
Of course, ssh should be improved. See

  http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=335697

(this is unrelated to the ssh bug you filled).

> Looking at strace output it appears that svn very rudely terminates its
> child processes with SIGKILL.  This makes ssh leave stray connection
> state files lying around.

This part may be a bug in Subversion, though. But if you start the
master connection manually (svn -fMN ...), there are no problems.

> Arguably this is a ssh bug (separate bug filed), but svn really should
> give the child process chance to exit gracefully.

I don't think this (bug 335531) is a ssh bug. Overwriting the files
could lead to a race condition in a "normal" use.

Anyway, "fixing" this bug only won't solve your problem, as I've
explained above.

-- 
Vincent Lefèvre <vincent at vinc17.org> - Web: <http://www.vinc17.org/>
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Work: CR INRIA - computer arithmetic / SPACES project at LORIA