pg.ddx.io pgsql-committers@postgresql.org mailing list archive
help / color / mirror / Atom feedFrom: Heikki Linnakangas <heikki.linnakangas@iki.fi>
To: pgsql-committers@lists.postgresql.org
Subject: pgsql: Fix backend state after a failed after-startup shmem request
Date: Fri, 28 Aug 2026 14:58:08 +0000
Message-ID: <E1wzy1v-00000002VYl-112K@gemulon.postgresql.org> (raw)
Fix backend state after a failed after-startup shmem request
RegisterShmemCallbacks() left the backend in a bad state, if an error
occurred in the callbacks or if an allocation failed. Firstly,
'shmem_request_state' was left in wrong state, causing a subsequent
call to RegisterShmemCallbacks() to wrongly take the postmaster
startup codepath or assertion failures in some other functions.
Secondly, the 'pending_shmem_requests' list was not properly cleaned
up, causing a subsequent RegisterShmemCallbacks() to try to process
the stale, already-freed requests.
To fix, add a PG_TRY() block to clean those things up on error.
Author: Ayush Tiwari <ayushtiwari.slg01@gmail.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: https://www.postgresql.org/message-id/CAJTYsWVRRWH48=PcuAo_2Y4Ap6M0QRmzxgUfFkNRtdWK74LjBQ@mail.gmail...
Backpatch-through: 19
Branch
------
master
Details
-------
https://git.postgresql.org/pg/commitdiff/c54b6979e033c6182518d4b33feb35771ae738ae
Modified Files
--------------
src/backend/storage/ipc/shmem.c | 72 +++++++++++++++-------
.../modules/test_shmem/t/001_late_shmem_alloc.pl | 28 +++++++++
src/test/modules/test_shmem/test_shmem.c | 28 ++++++++-
3 files changed, 104 insertions(+), 24 deletions(-)
view thread (2+ messages)
Message-ID: <E1wzy1v-00000002VYl-112K@gemulon.postgresql.org>
Permalink: ../E1wzy1v-00000002VYl-112K@gemulon.postgresql.org/
Also on: postgresql.org/message-id/E1wzy1v-00000002VYl-112K@gemulon.postgresql.org
reply
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-committers@postgresql.org
Cc: heikki.linnakangas@iki.fi, pgsql-committers@lists.postgresql.org
Subject: Re: pgsql: Fix backend state after a failed after-startup shmem request
In-Reply-To: <E1wzy1v-00000002VYl-112K@gemulon.postgresql.org>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox