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Subject: Re: Strange hang when calling signal()
To: Konstantin Belousov <kostikbel@gmail.com>, Gleb Popov <6yearold@gmail.com>
Cc: freebsd-hackers <freebsd-hackers@freebsd.org>
References: <CALH631mtb1Z-4v4+UuzCx0tX0Zt5LfoQR9+iags-nL7MRUhGLA@mail.gmail.com>
 <20180824185328.GE2340@kib.kiev.ua>
From: Eric van Gyzen <eric@vangyzen.net>
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Date: Fri, 24 Aug 2018 14:10:36 -0500
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On 8/24/18 1:53 PM, Konstantin Belousov wrote:
> Since then, we started locking most of that locks in parent around fork(2),
> all the code in lib/libthr/thread/thr_fork.c.  In particular, we lock rtld,
> malloc, and disable cancellation around fork.  So if your program used fork(2)
> but ended with the broken rtld it is worrying.
> 
> On the other hand, we do not do that for vfork(2).  So yes, the minimal

We also do not do that for rfork(2).  I think we should, but I have not 
done any research into it.

Eric