On 13/06/2011 16:07, Rainer Jung wrote: > I had some spare time for analyzing the crashes in > TestMapperWelcomeFiles. It seems there are several varieties, but at > least I do now understand enough to report here: > > In Http11AprProcessor.process() when parsing the request line fails, > e.g. it is not yet there, we add the socket back to the poller. Then we > check the endpoint for being paused. If so, we set "error" to true. > > At the end of process(), if "error" is true, we return > SocketState.CLOSED, which in turn lets the SocketProcessor closes the > socket (and destroys the native memory allocated with it). > > Now what I experience sporadically, is that the original thread A is > thrown off the CPU after adding the socket back to the poller, but > before proceeding. > > Another thread B now gets the socket from the poller, uses it for > request processing and at the end destroys it. Now A wakes up and > proceeds as described above, and since now the endpoint is paused, it > also tries to destroy the socket, leading to a crash. > > This seems to be a flaw. I suggest we add only to the poller if we know > no error occured and the endpoint is not paused. The patch for AjpApr is > simpler but similar. See for both classes: > > http://people.apache.org/~rjung/patches/tc7-apr-add_to_poller.patch > > I checked this patch against one full run of the test suite with HTTP > APR and also against 150 runs of TestMapperWelcomeFiles. No crashes or > errors any more. > > WDYT?
Analysis and patch make sense to me. Mark --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@tomcat.apache.org For additional commands, e-mail: dev-h...@tomcat.apache.org
