Hi, On 2018-12-17 15:35:01 -0800, Andres Freund wrote: > On 2018-12-16 13:48:00 -0800, Andres Freund wrote: > > On 2018-12-17 08:25:38 +1100, Thomas Munro wrote: > > > On Mon, Dec 17, 2018 at 7:57 AM Andres Freund <and...@anarazel.de> wrote: > > > > The interesting bit is that if I replace the _exit(2) in > > > > bgworker_quickdie() with an exit(2) (i.e. processing atexit handlers), > > > > or manully add an OPENSSL_cleanup() before the _exit(2), valgrind > > > > doesn't find errors. > > > > > > Weird. Well I can see that there were bugs last year where OpenSSL > > > failed to clean up its thread locals[1], and after they fixed that, > > > cases where it bogusly cleaned up someone else's thread locals[2]. > > > Maybe there is some interference between pthread keys or something > > > like that. > > > > > > [1] https://github.com/openssl/openssl/issues/3033 > > > [2] https://github.com/openssl/openssl/issues/3584 > > > > What confuses the heck out of me is that it happens on _exit(). Those > > issues ought to be only visible when doing exit(), no? > > > > I guess there's also a good argument to make that valgrind running it's > > intercept in the _exit() case is a bit dubious (given that's going to be > > used in cases where e.g. a signal handler might have interrupted a > > malloc), but given the stacktraces here I don't think that can be the > > cause. > > I've for now put --run-libc-freeres=no into skink's config. Locally that > "fixes" the issue for me, but of course is not a proper solution. But I > want to see whether that allows running all tests under valgrind.
Turns out to be caused by a glibc bug: https://sourceware.org/bugzilla/show_bug.cgi?id=24476 The reason it only fails if ssl is enabled, and only after the openssl randomness was integrated, is that openssl randomness initialization creates a TLS variable, which glibc then frees accidentally (as it tries to free something not initialized). Thus this can be "worked around" by doing something like shared_preload_libraries=pg_stat_statements, as dlopening a library initializes the relevant state. Greetings, Andres Freund
