Re: Segfaults in ConnectionHander

[Graham Dumpleton <gr...@dscpl.com.au>]

Changed subject heading. See more of what I have uncovered below.
Not sure where to go next.

Graham Dumpleton wrote ..
> > > Unlike suggestions by someone else that "self" seemed to be getting
> corrupted,
> > > it looks fine to me, and code simply crashed down in:
> > >
> > >  apr_bucket_read(b, &data, &size, APR_BLOCK_READ)
> > >
> > > on very first call to it. Thus need to start tracking into Apache itself
> > and see what
> > > there may be about bucket structures that isn't correct. This is where
> > I got to
> > > last time before I gave up, feeling it wasn't worth the effort at the
> > time. I'll try
> > > and build a version of Apache with debug so I can get a better stack
> > trace.
> > 
> > The first thing I'd check is for validity of b. Buckets use reference
> > counting much like Python, so sometimes it's possible for a bucket to
> > "self-distruct".
> 
> Starting to delve into the bucket now. Haven't looked at reference count
> stuff yet, but the b->type object seems to be bogus. This is where the
> read() function pointer is kept and since it is a bad value it is why it
> dies.

This is starting to look really ugly.

In _conn_read(), it first creates a bucket brigade from the connection
objects pool object. No chance of this being destroyed prematurely
as a result.

    bb = apr_brigade_create(c->pool, c->bucket_alloc);

Re: Segfaults in ConnectionHander

[Jim Gallacher <jp...@jgassociates.ca>]

Jim Gallacher wrote:
> Graham Dumpleton wrote:
> 
>> What I might speculate is that if the test in mod_python for the
>> connection handler is setup to run on a secondary listener port,
>> but with the primary still active, that it may trigger the problem
>> on other systems like Linux. Jim, you might want to try this and see
>> if you can duplicate it on Linux.
> 
> 
> I'll try it tonight.
> 

Graham,

I am not able to reproduce the problem using the configuration and 
example code you give in MODPYTHON-102. (Linux Debian 2.6.12-1-k7 kernel).

Jim

Re: Segfaults in ConnectionHander

[Jim Gallacher <jp...@jgassociates.ca>]

Graham Dumpleton wrote:

> What I might speculate is that if the test in mod_python for the
> connection handler is setup to run on a secondary listener port,
> but with the primary still active, that it may trigger the problem
> on other systems like Linux. Jim, you might want to try this and see
> if you can duplicate it on Linux.

I'll try it tonight.

Jim