#At file:///opt/local/work/next-mr-kostja/ based on revid:kostja@stripped
2926 Konstantin Osipov 2009-11-20
Backport of:
------------------------------------------------------------
revno: 2476.784.3
committer: davi@stripped
timestamp: Tue 2007-10-02 21:27:31 -0300
message:
Bug#25858 Some DROP TABLE under LOCK TABLES can cause deadlocks
When a client (connection) holds a lock on a table and attempts to
drop (obtain a exclusive lock) on a second table that is already
held by a second client and the second client then attempts to
drop the table that is held by the first client, leads to a
circular wait deadlock. This scenario is very similar to trying to
drop (or rename) a table while holding read locks and are
correctly forbidden.
The solution is to allow a drop table operation to continue only
if the table being dropped is write (exclusively) locked, or if
the table is temporary, or if the client is not holding any
locks. Using this scheme prevents the creation of a circular
chain in which each client is waiting for one table that the
next client in the chain is holding.
This is incompatible change, as can be seen by number of tests
cases that needed to be fixed, but is consistent with respect to
behavior of the different scenarios in which the circular wait
might happen.
@ mysql-test/r/drop.result
Test case result for Bug#25858
@ mysql-test/r/group_by.result
Fix test case result wrt drop table under lock tables -- unlock tables
before dropping table.
@ mysql-test/r/insert_notembedded.result
Fix test case result wrt drop table under lock tables -- unlock tables
before dropping table
@ mysql-test/r/lock.result
Fix test case result wrt drop table under lock tables -- unlock tables
before dropping table.
@ mysql-test/r/lock_multi.result
Fix test case result wrt drop table under lock tables -- unlock tables
before dropping table.
@ mysql-test/r/myisam.result
Fix test case result wrt drop table under lock tables -- unlock tables
before dropping table.
@ mysql-test/r/view.result
Fix test case result wrt drop table under lock tables -- unlock tables
before dropping table.
@ mysql-test/t/drop.test
Add test case for Bug#25858
@ mysql-test/t/group_by.test
Fix test case: unlock tables in preparation for a drop table. In some
circumstances, dropping tables while holding locks leads to a deadlock.
@ mysql-test/t/insert_notembedded.test
Fix test case: unlock tables in preparation for a drop table. In some
circumstances, dropping tables while holding locks leads to a deadlock.
@ mysql-test/t/lock.test
Fix test case: unlock tables in preparation for a drop table. In some
circumstances, dropping tables while holding locks leads to a deadlock.
@ mysql-test/t/lock_multi.test
Fix test case: unlock tables in preparation for a drop table. In some
circumstances, dropping tables while holding locks leads to a deadlock.
@ mysql-test/t/myisam.test
Fix test case: unlock tables in preparation for a drop table. In some
circumstances, dropping tables while holding locks leads to a deadlock.
@ mysql-test/t/query_cache_notembedded.test
Fix test case: unlock tables in preparation for a drop table. In some
circumstances, dropping tables while holding locks leads to a deadlock.
@ mysql-test/t/view.test
Fix test case: unlock tables in preparation for a drop table. In some
circumstances, dropping tables while holding locks leads to a deadlock.
@ sql/lock.cc
When trying to obtain a name lock under lock tables, ensure that the table is properly exclusively locked and fail otherwise.
modified:
mysql-test/r/drop.result
mysql-test/r/group_by.result
mysql-test/r/insert_notembedded.result
mysql-test/r/lock.result
mysql-test/r/lock_multi.result
mysql-test/r/myisam.result
mysql-test/r/query_cache_notembedded.result
mysql-test/r/view.result
mysql-test/t/drop.test
mysql-test/t/group_by.test
mysql-test/t/insert_notembedded.test
mysql-test/t/lock.test
mysql-test/t/lock_multi.test
mysql-test/t/myisam.test
mysql-test/t/query_cache_notembedded.test
mysql-test/t/view.test
sql/lock.cc
=== modified file 'mysql-test/r/drop.result'
--- a/mysql-test/r/drop.result 2009-10-22 18:22:53 +0000
+++ b/mysql-test/r/drop.result 2009-11-20 19:51:12 +0000
@@ -86,6 +86,26 @@ select 1;
1
1
unlock tables;
+drop table if exists t1,t2;
+create table t1 (a int);
+create table t2 (a int);
+lock table t1 read;
+drop table t2;
+ERROR HY000: Table 't2' was not locked with LOCK TABLES
+drop table t1;
+ERROR HY000: Table 't1' was locked with a READ lock and can't be updated
+unlock tables;
+drop table t1,t2;
+create table t1 (i int);
+create table t2 (i int);
+lock tables t1 read;
+lock tables t2 read;
+drop table t1;
+ERROR HY000: Table 't1' was not locked with LOCK TABLES
+drop table t1,t2;
+ERROR HY000: Table 't1' was locked with a READ lock and can't be updated
+unlock tables;
+drop table t1,t2;
End of 5.0 tests
create database mysql_test;
create table mysql_test.t1(f1 int);
=== modified file 'mysql-test/r/group_by.result'
--- a/mysql-test/r/group_by.result 2009-02-26 17:17:06 +0000
+++ b/mysql-test/r/group_by.result 2009-11-20 19:51:12 +0000
@@ -107,8 +107,9 @@ SELECT cid, CONCAT(firstname, ' ', surna
cid CONCAT(firstname, ' ', surname) COUNT(call_id)
SELECT HIGH_PRIORITY cid, CONCAT(firstname, ' ', surname), COUNT(call_id) FROM t1 LEFT JOIN t2 ON cid=contact_id WHERE firstname like '%foo%' GROUP BY cid ORDER BY surname, firstname;
cid CONCAT(firstname, ' ', surname) COUNT(call_id)
-drop table t1,t2;
+drop table t2;
unlock tables;
+drop table t1;
CREATE TABLE t1 (
bug_id mediumint(9) NOT NULL auto_increment,
groupset bigint(20) DEFAULT '0' NOT NULL,
=== modified file 'mysql-test/r/insert_notembedded.result'
--- a/mysql-test/r/insert_notembedded.result 2007-09-06 16:22:34 +0000
+++ b/mysql-test/r/insert_notembedded.result 2009-11-20 19:51:12 +0000
@@ -122,5 +122,6 @@ a b
connection: default
select * from t1;
a b
+unlock tables;
drop table t1;
set low_priority_updates=default;
=== modified file 'mysql-test/r/lock.result'
--- a/mysql-test/r/lock.result 2009-03-05 14:22:33 +0000
+++ b/mysql-test/r/lock.result 2009-11-20 19:51:12 +0000
@@ -48,6 +48,9 @@ unlock tables;
lock tables t1 write, t1 as t1_alias read;
insert into t1 select index1,nr from t1 as t1_alias;
drop table t1,t2;
+ERROR HY000: Table 't2' was not locked with LOCK TABLES
+unlock tables;
+drop table t1,t2;
create table t1 (c1 int);
create table t2 (c1 int);
create table t3 (c1 int);
@@ -69,6 +72,9 @@ ERROR HY000: Table 't2' was locked with
delete t2 from t1,t2 where t1.a=t2.a;
ERROR HY000: Table 't2' was locked with a READ lock and can't be updated
drop table t1,t2;
+ERROR HY000: Table 't2' was locked with a READ lock and can't be updated
+unlock tables;
+drop table t2,t1;
End of 4.1 tests.
drop table if exists t1;
create table t1 (a int);
=== modified file 'mysql-test/r/lock_multi.result'
--- a/mysql-test/r/lock_multi.result 2009-07-10 23:12:13 +0000
+++ b/mysql-test/r/lock_multi.result 2009-11-20 19:51:12 +0000
@@ -27,6 +27,7 @@ update t1,t2 set c=a where b=d;
select c from t2;
c
2
+unlock tables;
drop table t1;
drop table t2;
create table t1 (a int);
=== modified file 'mysql-test/r/myisam.result'
--- a/mysql-test/r/myisam.result 2009-10-27 14:27:27 +0000
+++ b/mysql-test/r/myisam.result 2009-11-20 19:51:12 +0000
@@ -529,6 +529,7 @@ select straight_join * from t1,t2 force
a a b
1 1 1
2 2 1
+unlock tables;
drop table t1,t2;
CREATE TABLE t1 (c1 varchar(250) NOT NULL);
CREATE TABLE t2 (c1 varchar(250) NOT NULL, PRIMARY KEY (c1));
@@ -542,6 +543,7 @@ INSERT INTO t2 VALUES ('test000001'), ('
SELECT t1.c1 AS t1c1, t2.c1 AS t2c1 FROM t1, t2
WHERE t1.c1 = t2.c1 HAVING t1c1 != t2c1;
t1c1 t2c1
+UNLOCK TABLES;
DROP TABLE t1,t2;
CREATE TABLE t1 (`a` int(11) NOT NULL default '0', `b` int(11) NOT NULL default '0', UNIQUE KEY `a` USING RTREE (`a`,`b`)) ENGINE=MyISAM;
Got one of the listed errors
=== modified file 'mysql-test/r/query_cache_notembedded.result'
--- a/mysql-test/r/query_cache_notembedded.result 2009-02-13 19:32:24 +0000
+++ b/mysql-test/r/query_cache_notembedded.result 2009-11-20 19:51:12 +0000
@@ -93,6 +93,7 @@ a
3
SELECT * FROM t1;
a
+UNLOCK TABLES;
drop table t1;
flush query cache;
reset query cache;
=== modified file 'mysql-test/r/view.result'
--- a/mysql-test/r/view.result 2009-10-19 13:14:43 +0000
+++ b/mysql-test/r/view.result 2009-11-20 19:51:12 +0000
@@ -1104,6 +1104,9 @@ select * from t2;
ERROR HY000: Table 't2' was not locked with LOCK TABLES
drop view v1;
drop table t1, t2;
+ERROR HY000: Table 't1' was locked with a READ lock and can't be updated
+unlock tables;
+drop table t1, t2;
create table t1 (a int);
create view v1 as select * from t1 where a < 2 with check option;
insert into v1 values(1);
=== modified file 'mysql-test/t/drop.test'
--- a/mysql-test/t/drop.test 2009-10-22 18:22:53 +0000
+++ b/mysql-test/t/drop.test 2009-11-20 19:51:12 +0000
@@ -124,6 +124,39 @@ disconnect addconroot1;
--source include/wait_until_disconnected.inc
connection default;
+#
+# Bug#25858 Some DROP TABLE under LOCK TABLES can cause deadlocks
+#
+
+--disable_warnings
+drop table if exists t1,t2;
+--enable_warnings
+create table t1 (a int);
+create table t2 (a int);
+lock table t1 read;
+--error ER_TABLE_NOT_LOCKED
+drop table t2;
+--error ER_TABLE_NOT_LOCKED_FOR_WRITE
+drop table t1;
+unlock tables;
+drop table t1,t2;
+connect (addconroot, localhost, root,,);
+connection default;
+create table t1 (i int);
+create table t2 (i int);
+lock tables t1 read;
+connection addconroot;
+lock tables t2 read;
+--error ER_TABLE_NOT_LOCKED
+drop table t1;
+connection default;
+--error ER_TABLE_NOT_LOCKED_FOR_WRITE
+drop table t1,t2;
+disconnect addconroot;
+connection default;
+unlock tables;
+drop table t1,t2;
+
--echo End of 5.0 tests
#
=== modified file 'mysql-test/t/group_by.test'
--- a/mysql-test/t/group_by.test 2009-02-26 17:17:06 +0000
+++ b/mysql-test/t/group_by.test 2009-11-20 19:51:12 +0000
@@ -120,8 +120,9 @@ SELECT cid, CONCAT(firstname, ' ', surna
SELECT cid, CONCAT(firstname, ' ', surname), COUNT(call_id) FROM t1 LEFT JOIN t2 ON cid=contact_id WHERE firstname like '%foo%' GROUP BY cid ORDER BY NULL;
SELECT HIGH_PRIORITY cid, CONCAT(firstname, ' ', surname), COUNT(call_id) FROM t1 LEFT JOIN t2 ON cid=contact_id WHERE firstname like '%foo%' GROUP BY cid ORDER BY surname, firstname;
-drop table t1,t2;
+drop table t2;
unlock tables;
+drop table t1;
#
# Test of group by bug in bugzilla
=== modified file 'mysql-test/t/insert_notembedded.test'
--- a/mysql-test/t/insert_notembedded.test 2007-09-06 16:22:34 +0000
+++ b/mysql-test/t/insert_notembedded.test 2009-11-20 19:51:12 +0000
@@ -185,5 +185,6 @@ select * from t1;
connection default;
disconnect update;
disconnect select;
+unlock tables;
drop table t1;
set low_priority_updates=default;
=== modified file 'mysql-test/t/lock.test'
--- a/mysql-test/t/lock.test 2009-03-05 14:22:33 +0000
+++ b/mysql-test/t/lock.test 2009-11-20 19:51:12 +0000
@@ -58,6 +58,9 @@ insert into t1 select index1,nr from t1;
unlock tables;
lock tables t1 write, t1 as t1_alias read;
insert into t1 select index1,nr from t1 as t1_alias;
+--error ER_TABLE_NOT_LOCKED
+drop table t1,t2;
+unlock tables;
drop table t1,t2;
#
@@ -90,7 +93,10 @@ delete t1 from t1,t2 where t1.a=t2.a;
delete from t2 using t1,t2 where t1.a=t2.a;
--error 1099
delete t2 from t1,t2 where t1.a=t2.a;
+--error ER_TABLE_NOT_LOCKED_FOR_WRITE
drop table t1,t2;
+unlock tables;
+drop table t2,t1;
--echo End of 4.1 tests.
=== modified file 'mysql-test/t/lock_multi.test'
--- a/mysql-test/t/lock_multi.test 2009-11-10 14:23:55 +0000
+++ b/mysql-test/t/lock_multi.test 2009-11-20 19:51:12 +0000
@@ -76,6 +76,7 @@ update t1,t2 set c=a where b=d;
connection reader;
select c from t2;
connection locker;
+unlock tables;
drop table t1;
drop table t2;
=== modified file 'mysql-test/t/myisam.test'
--- a/mysql-test/t/myisam.test 2009-10-27 14:27:27 +0000
+++ b/mysql-test/t/myisam.test 2009-11-20 19:51:12 +0000
@@ -503,6 +503,7 @@ insert into t2 values(2,0);
disconnect root;
connection default;
select straight_join * from t1,t2 force index (primary) where t1.a=t2.a;
+unlock tables;
drop table t1,t2;
#
# Full key.
@@ -520,6 +521,7 @@ disconnect con1;
connection default;
SELECT t1.c1 AS t1c1, t2.c1 AS t2c1 FROM t1, t2
WHERE t1.c1 = t2.c1 HAVING t1c1 != t2c1;
+UNLOCK TABLES;
DROP TABLE t1,t2;
# End of 4.0 tests
=== modified file 'mysql-test/t/query_cache_notembedded.test'
--- a/mysql-test/t/query_cache_notembedded.test 2009-02-13 19:32:24 +0000
+++ b/mysql-test/t/query_cache_notembedded.test 2009-11-20 19:51:12 +0000
@@ -99,6 +99,7 @@ connection root2;
SELECT * FROM t1;
connection root;
SELECT * FROM t1;
+UNLOCK TABLES;
drop table t1;
connection default;
disconnect root;
=== modified file 'mysql-test/t/view.test'
--- a/mysql-test/t/view.test 2009-09-16 06:55:17 +0000
+++ b/mysql-test/t/view.test 2009-11-20 19:51:12 +0000
@@ -1017,6 +1017,9 @@ select * from v1;
-- error ER_TABLE_NOT_LOCKED
select * from t2;
drop view v1;
+--error ER_TABLE_NOT_LOCKED_FOR_WRITE
+drop table t1, t2;
+unlock tables;
drop table t1, t2;
#
=== modified file 'sql/lock.cc'
--- a/sql/lock.cc 2009-11-20 19:15:50 +0000
+++ b/sql/lock.cc 2009-11-20 19:51:12 +0000
@@ -1028,6 +1028,7 @@ int lock_table_name(THD *thd, TABLE_LIST
char key[MAX_DBKEY_LENGTH];
char *db= table_list->db;
uint key_length;
+ bool found_locked_table= FALSE;
HASH_SEARCH_STATE state;
DBUG_ENTER("lock_table_name");
DBUG_PRINT("enter",("db: %s name: %s", db, table_list->table_name));
@@ -1043,6 +1044,13 @@ int lock_table_name(THD *thd, TABLE_LIST
table = (TABLE*) my_hash_next(&open_cache,(uchar*) key,
key_length, &state))
{
+ if (table->reginfo.lock_type < TL_WRITE)
+ {
+ if (table->in_use == thd)
+ found_locked_table= TRUE;
+ continue;
+ }
+
if (table->in_use == thd)
{
DBUG_PRINT("info", ("Table is in use"));
@@ -1053,6 +1061,17 @@ int lock_table_name(THD *thd, TABLE_LIST
}
}
+ if (thd->locked_tables && thd->locked_tables->table_count &&
+ ! find_temporary_table(thd, table_list->db, table_list->table_name))
+ {
+ if (found_locked_table)
+ my_error(ER_TABLE_NOT_LOCKED_FOR_WRITE, MYF(0), table_list->alias);
+ else
+ my_error(ER_TABLE_NOT_LOCKED, MYF(0), table_list->alias);
+
+ DBUG_RETURN(-1);
+ }
+
if (!(table= table_cache_insert_placeholder(thd, key, key_length)))
DBUG_RETURN(-1);
Attachment: [text/bzr-bundle] bzr/kostja@sun.com-20091120195112-qntdy86torkjh1j0.bundle
| Thread |
|---|
| • bzr commit into mysql-5.6-next-mr branch (kostja:2926) Bug#25858 | Konstantin Osipov | 20 Nov |
