On 2017-03-16 09:27:59 -0400, Robert Haas wrote: > On Thu, Mar 16, 2017 at 5:13 AM, Petr Jelinek > <petr.jeli...@2ndquadrant.com> wrote: > > Hmm now that you mention it, I remember discussing something similar > > with you last year in Dallas in regards to parallel query. IIRC Windows > > should not have this problem but other systems with EXEC_BACKEND do. > > Don't remember the details though. > > Generally, extension code can't use bgw_main safely, and must use > bgw_library_name and bgw_function_name. But bgw_main is supposedly > safe for core code.
I indeed think it's not safe, and it's going to get less and less safe on windows (or EXEC_BACKEND). I don't think we can afford to disable ASLR in the long run (I indeed supect that'll just be disallowed at some point), and that's the only thing making it safe-ish in combination with EXEC_BACKEND. > If it's not even safe there, then I guess we should remove it entirely > as a useless foot-gun. I indeed think that's the right consequence. One question is what to replace it with exactly - are we guaranteed we can dynamically lookup symbols by name in the main binary on every platform? Alternatively we can just hardcode a bunch of bgw_function_name values that are matched to specific functions if bgw_library_name is NULL - I suspect that'd be the easiest / least worrysome portability-wise. Greetings, Andres Freund -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
