On 2014-05-18 23:52:32 +0200, Andres Freund wrote: > On 2014-05-18 17:41:17 -0400, Tom Lane wrote: > > Christoph Berg <c...@df7cb.de> writes: > > > Re: Andres Freund 2014-05-18 <20140518091445.gu23...@alap3.anarazel.de> > > >> Did you measure how large the stack actually was when you got the > > >> SIGBUS? Should be possible to determine that by computing the offset > > >> using some local stack variable in one of the depeest stack frames. > > > > > Looking at /proc/*/maps, the stack is ffb38000-ffd1e000 = 1944kB for a > > > process that just got SIGBUS. This seems to be in line with > > > stack_base_ptr = 0xffd1c317 and the fcinfo address in > > > > OK, so the problem is that getrlimit(RLIMIT_STACK) is lying to us about > > the available stack depth. I'd classify that as a kernel bug. I wonder > > if it's a different manifestation of this issue: > > https://bugzilla.redhat.com/show_bug.cgi?id=952946 > > That'd explain why I couldn't reproduce it. And I seme to recall some > messages about the hardening stuff in debian accidentally being lost > some time ago. So if that got re-introduced into 9.4... The CFLAGS > certainly indicate that -pie is getting used.
Indeed. If I add -pie to my 32bit vpath's configure invocation it crashes, too. Not that that helps much to resolve the bug, given it's been sedentary for a long while :(. Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
