Date: Wed, 1 Feb 2023 08:06:09 -0800
From: Nathan Bossart <nathandbossart@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Andres Freund <andres@anarazel.de>,
	Thomas Munro <thomas.munro@gmail.com>,
	Fujii Masao <fujii@postgresql.org>,
	Michael Paquier <michael@paquier.xyz>,
	Postgres hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Weird failure with latches in curculio on v15
Message-ID: <20230201160609.GA3197588@nathanxps13>
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On Wed, Feb 01, 2023 at 10:12:26AM -0500, Tom Lane wrote:
> Andres Freund <andres@anarazel.de> writes:
>> On 2023-02-01 16:21:16 +1300, Thomas Munro wrote:
>>> It's always in proc_exit() in StartupProcShutdownHandler(), a SIGTERM
>>> handler which is allowed to call that while in_restore_command is
>>> true.
> 
>> Ugh, no wonder we're getting crashes. This whole business seems bogus as
>> hell.
> 
> Indeed :-(

Ugh.  My bad.

> The fundamental issue is that we have no good way to break out
> of system(), and I think the original idea was that
> in_restore_command would be set *only* for the duration of the
> system() call.  That's clearly been lost sight of completely,
> but maybe as a stopgap we could try to get back to that.

+1.  I'll produce some patches.

-- 
Nathan Bossart
Amazon Web Services: https://aws.amazon.com