From: Eli Zaretskii <eliz@gnu.org>
To: Andreas Schwab <schwab@linux-m68k.org>
Cc: phst@google.com, p.stephani2@gmail.com, emacs-devel@gnu.org
Subject: Re: scratch/sigchld-fd 8f0ce42 1/2: Fix deadlock when receiving SIGCHLD during 'pselect'.
Date: Wed, 20 Jan 2021 19:03:14 +0200 [thread overview]
Message-ID: <83ft2v7d7x.fsf@gnu.org> (raw)
In-Reply-To: <87o8hjv9pw.fsf@igel.home> (message from Andreas Schwab on Wed, 20 Jan 2021 17:44:59 +0100)
> From: Andreas Schwab <schwab@linux-m68k.org>
> Cc: emacs-devel@gnu.org, phst@google.com, p.stephani2@gmail.com
> Date: Wed, 20 Jan 2021 17:44:59 +0100
>
> >> You cannot do that. That creates races all over the place.
> >
> > What kind of races, and where in our code? please elaborate.
>
> The signal can occur anytime. When it interrupts the setup of the
> pselect call, chaos will ensure. The only way to avoid that is to block
> the signal around the call.
What I described would be in the signal handler.
> Doing anything non-trivial in a signal handler is bound to problems.
Yes, I know. I think resetting a bit in a variable is more trivial
than, say, writing to a pipe, something that we do now.
next prev parent reply other threads:[~2021-01-20 17:03 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20210116184947.2105.45267@vcs0.savannah.gnu.org>
[not found] ` <20210116184949.3C17C211A5@vcs0.savannah.gnu.org>
2021-01-19 15:10 ` scratch/sigchld-fd 8f0ce42 1/2: Fix deadlock when receiving SIGCHLD during 'pselect' Eli Zaretskii
2021-01-19 18:21 ` Philipp Stephani
2021-01-19 19:14 ` Eli Zaretskii
2021-01-19 20:22 ` Philipp Stephani
2021-01-20 15:05 ` Eli Zaretskii
2021-01-23 17:36 ` Philipp Stephani
2021-01-23 18:23 ` Eli Zaretskii
2021-01-23 18:30 ` Philipp Stephani
2021-01-19 20:46 ` Andreas Schwab
2021-01-19 20:58 ` Philipp Stephani
2021-01-20 18:07 ` Andreas Schwab
2021-01-20 3:37 ` Eli Zaretskii
2021-01-20 8:37 ` Andreas Schwab
2021-01-20 8:52 ` Eli Zaretskii
2021-01-20 9:18 ` Andreas Schwab
2021-01-20 10:14 ` Eli Zaretskii
2021-01-20 10:17 ` Andreas Schwab
2021-01-20 15:30 ` Eli Zaretskii
2021-01-20 15:48 ` Andreas Schwab
2021-01-20 16:40 ` Eli Zaretskii
2021-01-20 16:44 ` Andreas Schwab
2021-01-20 17:03 ` Eli Zaretskii [this message]
2021-01-20 17:30 ` Andreas Schwab
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