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 <43712AD8-AF1C-4E2D-9AC7-A37BA7A752B6@yandex-team.ru> <Z76e7f-dmnqnJ4Uw@paquier.xyz>
In-Reply-To: <Z76e7f-dmnqnJ4Uw@paquier.xyz>
From: Maxim Orlov <orlovmg@gmail.com>
Date: Wed, 26 Feb 2025 09:57:45 +0300
Message-ID: <CACG=ezbScO5O2CTZYy-Rqs-VHQ_f3aaRWL6VQZpyjC4uMVVDoA@mail.gmail.com>
Subject: Re: Spinlock can be released twice in procsignal.c
To: Michael Paquier <michael@paquier.xyz>
Cc: Andrey Borodin <x4mmm@yandex-team.ru>, "Maksim.Melnikov" <m.melnikov@postgrespro.ru>, 
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Heikki Linnakangas <hlinnaka@iki.fi>, 
	Jelte Fennema-Nio <postgres@jeltef.nl>
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On Wed, 26 Feb 2025 at 07:56, Michael Paquier <michael@paquier.xyz> wrote:

>
> This fix is not correct.  No system function calls (well basically
> most of them) or even more no PostgreSQL-specific calls should happen
> while holding a spinlock.  elog() is a good example of what not to do.
> One example: imagine a palloc failure while holding this spinlock in
> this elog().


Indeed. PFA the correct one.


-- 
Best regards,
Maxim Orlov.

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<div dir=3D"ltr"><div dir=3D"ltr"><br></div><div class=3D"gmail_quote gmail=
_quote_container"><div dir=3D"ltr" class=3D"gmail_attr">On Wed, 26 Feb 2025=
 at 07:56, Michael Paquier &lt;<a href=3D"mailto:michael@paquier.xyz">micha=
el@paquier.xyz</a>&gt; wrote:<br></div><blockquote class=3D"gmail_quote" st=
yle=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padd=
ing-left:1ex"><br>
This fix is not correct.=C2=A0 No system function calls (well basically<br>
most of them) or even more no PostgreSQL-specific calls should happen<br>
while holding a spinlock.=C2=A0 elog() is a good example of what not to do.=
<br>
One example: imagine a palloc failure while holding this spinlock in<br>
this elog().</blockquote><div><br></div><div>Indeed. PFA the correct one.</=
div></div><div><br clear=3D"all"></div><br><span class=3D"gmail_signature_p=
refix">-- </span><br><div dir=3D"ltr" class=3D"gmail_signature"><div dir=3D=
"ltr"><div>Best regards,<br></div><div>Maxim Orlov.</div></div></div></div>

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