1berry/MariaDB-server
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

MDEV-24864 Fatal error in buf_page_get_low() / fseg_page_is_free()

Browse Source 
The fix of MDEV-24569 and MDEV-24695 introduced a race condition when
a table is being rebuilt or dropped during the fseg_page_is_free() check.
The server would occasionally crash during the execution of the test
encryption.create_or_replace.

The fil_space_t::STOPPING flag can be set by DDL operations. Normally,
such concurrent operations are prevented by a metadata lock (MDL).
However, neither the change buffer merge nor the fil_crypt_thread() are
protected by MDL.

fil_crypt_read_crypt_data(), xdes_get_descriptor_const(): Pass the
BUF_GET_POSSIBLY_FREED flag to avoid the fatal error in buf_page_get_low()
if a DDL operation was just initiated.
This commit is contained in:
Marko Mäkelä 2021-02-15 09:37:01 +02:00 committed by Sergei Golubchik
parent f13f966304
commit 638ede5bef
2 changed files with 12 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
storage/innobase/fil/fil0crypt.cc
View File

@ -1,6 +1,6 @@
/*****************************************************************************
Copyright (C) 2013, 2015, Google Inc. All Rights Reserved.
Copyright (c) 2014, 2020, MariaDB Corporation.
Copyright (c) 2014, 2021, MariaDB Corporation.
This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
@ -991,10 +991,13 @@ fil_crypt_read_crypt_data(fil_space_t* space)
const ulint zip_size = space->zip_size();
mtr_t mtr;
mtr.start();
if (buf_block_t* block = buf_page_get(page_id_t(space->id, 0),
zip_size, RW_S_LATCH, &mtr)) {
if (buf_block_t* block = buf_page_get_gen(page_id_t(space->id, 0),
zip_size, RW_S_LATCH,
nullptr,
BUF_GET_POSSIBLY_FREED,
__FILE__, __LINE__, &mtr)) {
mutex_enter(&fil_system.mutex);
if (!space->crypt_data) {
if (!space->crypt_data && !space->is_stopping()) {
space->crypt_data = fil_space_read_crypt_data(
zip_size, block->frame);
}

7
storage/innobase/fsp/fsp0fsp.cc
View File

@ -410,8 +410,11 @@ xdes_get_descriptor_const(
const ulint zip_size = space->zip_size();
if (buf_block_t* block = buf_page_get(page_id_t(space->id, page),
zip_size, RW_S_LATCH, mtr)) {
if (buf_block_t* block = buf_page_get_gen(page_id_t(space->id, page),
zip_size, RW_S_LATCH,
nullptr,
BUF_GET_POSSIBLY_FREED,
__FILE__, __LINE__, mtr)) {
buf_block_dbg_add_level(block, SYNC_FSP_PAGE);
ut_ad(page != 0 || space->free_limit == mach_read_from_4(