mirror of
https://github.com/gentoo-mirror/gentoo.git
synced 2026-07-29 10:18:08 -07:00
b115719c80
Regression can cause replicas to deadlock. Apply upstream patch. Signed-off-by: Patrick Lauer <patrick@gentoo.org>
63 lines
2.6 KiB
Diff
63 lines
2.6 KiB
Diff
From: Heikki Linnakangas <heikki.linnakangas@iki.fi>
|
|
Date: Wed, 27 May 2026 08:49:50 +0000 (+0300)
|
|
Subject: Fix self-deadlock when replaying WAL generated by older minor version
|
|
X-Git-Url: http://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff_plain;h=2dfe75f9844f29f8b2621ed68ee12e577f05e7f3
|
|
|
|
Fix self-deadlock when replaying WAL generated by older minor version
|
|
|
|
Commit 77dff5d937 introduced a SimpleLruWriteAll() call when replaying
|
|
multixact WAL records generated by older minor versions. However,
|
|
SimpleLruWriteAll() acquires the SLRU lock and on v16 and below, it's
|
|
called while already holding the lock, leading to self-deadlock.
|
|
Version 17 and 18 did not have that problem, because in those versions
|
|
the lock is acquired later in the function.
|
|
|
|
To fix, acquire MultiXactOffsetSLRULock later in RecordNewMultiXact(),
|
|
at the same place where it's acquired on version 17 and 18.
|
|
|
|
Author: Andrey Borodin <x4mmm@yandex-team.ru>
|
|
Reported-by: Radim Marek <radim@boringsql.com>
|
|
Discussion: https://www.postgresql.org/message-id/19490-9c59c6a583513b99@postgresql.org
|
|
Backpatch-through: 14-16
|
|
---
|
|
|
|
diff --git a/src/backend/access/transam/multixact.c b/src/backend/access/transam/multixact.c
|
|
index 0af1c61a4cc..8b5220d8aab 100644
|
|
--- a/src/backend/access/transam/multixact.c
|
|
+++ b/src/backend/access/transam/multixact.c
|
|
@@ -887,8 +887,6 @@ RecordNewMultiXact(MultiXactId multi, MultiXactOffset offset,
|
|
MultiXactOffset *next_offptr;
|
|
MultiXactOffset next_offset;
|
|
|
|
- LWLockAcquire(MultiXactOffsetSLRULock, LW_EXCLUSIVE);
|
|
-
|
|
/* position of this multixid in the offsets SLRU area */
|
|
pageno = MultiXactIdToOffsetPage(multi);
|
|
entryno = MultiXactIdToOffsetEntry(multi);
|
|
@@ -950,6 +948,8 @@ RecordNewMultiXact(MultiXactId multi, MultiXactOffset offset,
|
|
{
|
|
elog(DEBUG1, "next offsets page is not initialized, initializing it now");
|
|
|
|
+ LWLockAcquire(MultiXactOffsetSLRULock, LW_EXCLUSIVE);
|
|
+
|
|
/* Create and zero the page */
|
|
slotno = SimpleLruZeroPage(MultiXactOffsetCtl, next_pageno);
|
|
|
|
@@ -957,6 +957,8 @@ RecordNewMultiXact(MultiXactId multi, MultiXactOffset offset,
|
|
SimpleLruWritePage(MultiXactOffsetCtl, slotno);
|
|
Assert(!MultiXactOffsetCtl->shared->page_dirty[slotno]);
|
|
|
|
+ LWLockRelease(MultiXactOffsetSLRULock);
|
|
+
|
|
/*
|
|
* Remember that we initialized the page, so that we don't zero it
|
|
* again at the XLOG_MULTIXACT_ZERO_OFF_PAGE record.
|
|
@@ -975,6 +977,7 @@ RecordNewMultiXact(MultiXactId multi, MultiXactOffset offset,
|
|
* concurrently, we might race ahead and get called before the previous
|
|
* multixid.
|
|
*/
|
|
+ LWLockAcquire(MultiXactOffsetSLRULock, LW_EXCLUSIVE);
|
|
|
|
/*
|
|
* Note: we pass the MultiXactId to SimpleLruReadPage as the "transaction"
|