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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: Tomas Vondra <tomas.vondra@enterprisedb.com>, pgsql-hackers@postgresql.org,
        Tomas Vondra <tv@fuzzy.cz>,
        Anastasia Lubennikova <lubennikovaav@gmail.com>,
        Pavan Deolasee <pavan.deolasee@gmail.com>,
        Jeff Janes <jeff.janes@gmail.com>
Subject: Re: hio.c does visibilitymap_pin()/IO while holding buffer lock
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Comments: In-reply-to Andres Freund <andres@anarazel.de>
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Andres Freund <andres@anarazel.de> writes:
> On 2023-03-25 14:34:25 +0100, Tomas Vondra wrote:
>> Can't we ensure we actually lock the vm buffer too in ReadBufferBI,
>> before calling ReadBufferExtended? Or am I confused and that's not
>> possible for some reason?

> Note that this is using P_NEW. I.e. we don't know the buffer location yet.

Maybe the relation-extension logic needs to include the ability to get
the relevant vm page?

			regards, tom lane