innodb_read_only tries to modify files if transactions were recovered in COMMITTED state

diff --git a/storage/innobase/trx/trx0trx.c b/storage/innobase/trx/trx0trx.c

index 151e70013f9..8f6f90bf36d 100644

--- a/storage/innobase/trx/trx0trx.c

+++ b/storage/innobase/trx/trx0trx.c

@@ -43,6 +43,7 @@ Created 3/26/1996 Heikki Tuuri

 #include "trx0xa.h"

 #include "trx0purge.h"

 #include "ha_prototypes.h"

+#include "my_sys.h" /* DEBUG_SYNC_C */

 /** Dummy session used currently in MySQL interface */

 UNIV_INTERN sess_t*		trx_dummy_sess = NULL;

@@ -985,6 +986,7 @@ trx_commit_off_kernel(

 	if (lsn) {

 		mutex_exit(&kernel_mutex);

+		DEBUG_SYNC_C("after_trx_committed_in_memory");

 		if (trx->insert_undo != NULL) {

--source include/have_innodb.inc

--source include/have_debug.inc

--source include/have_debug_sync.inc

# need to restart server

--source include/not_embedded.inc

--connect(con1, localhost, root)

CREATE TABLE t(a INT PRIMARY KEY) ENGINE=InnoDB;

INSERT INTO t VALUES(1);

BEGIN;

# Generate insert_undo log.

INSERT INTO t VALUES(2);

# Generate update_undo log.

DELETE FROM t WHERE a=2;

--connect(con2, localhost, root)

--echo # Normal MariaDB shutdown would roll back the above transaction.

--echo # We want the transaction to remain open, so we will kill the server

--echo # after ensuring that any non-transactional files are clean.

FLUSH TABLES;

--echo # Create another transaction that will be recovered as COMMITTED.

BEGIN;

# Generate multiple pages of both insert_undo and update_undo, so that

# the state TRX_UNDO_CACHE will not be chosen.

--disable_query_log

let $n= 10000;

while ($n) {

dec $n;

eval INSERT INTO t VALUES(-$n);

eval DELETE FROM t WHERE a=-$n;

}

--enable_query_log

SET DEBUG_SYNC='after_trx_committed_in_memory SIGNAL committed WAIT_FOR ever';

send COMMIT;

connection default;

SET DEBUG_SYNC='now WAIT_FOR committed';

--echo # Ensure that the above incomplete transactions become durable.

SET GLOBAL innodb_flush_log_at_trx_commit=1;

BEGIN;

INSERT INTO t VALUES(-10000);

ROLLBACK;

--let $restart_parameters= --innodb-force-recovery=3

--let $shutdown_timeout= 0

--source include/restart_mysqld.inc

--let $shutdown_timeout= 30

--disconnect con1

--disconnect con2

SELECT * FROM t;

SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;

SELECT * FROM t;

UPDATE t SET a=3 WHERE a=1;

--let $restart_parameters= --loose-innodb-read-only

--source include/restart_mysqld.inc

--echo # Starting with MariaDB 10.2, innodb_read_only implies READ UNCOMMITTED.

--echo # In earlier versions, this would return the last committed version

--echo # (empty table)!

SELECT * FROM t;

SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;

SELECT * FROM t;

--let $restart_parameters=

--source include/restart_mysqld.inc

SELECT * FROM t;

DROP TABLE t;

180118 16:04:45 [Note] InnoDB: Starting shutdown...

2018-01-18 16:04:46 7fe21c330700  InnoDB: Assertion failure in thread 140609112442624 in file lock0lock.cc line 7006

InnoDB: Failing assertion: trx_state_eq(trx, TRX_STATE_ACTIVE)

2018-01-18 16:04:47 7f20f39c5080  InnoDB: Assertion failure in thread 139779502788736 in file mtr0mtr.cc line 322

InnoDB: Failing assertion: !srv_read_only_mode

…

#6  0x00007f20ec9ae658 in mtr_commit (mtr=0x7ffea6e73e38) at /mariadb/10.0/storage/innobase/mtr/mtr0mtr.cc:322

#7  0x00007f20ecaed2e9 in trx_undo_seg_free (undo=0x33f7478) at /mariadb/10.0/storage/innobase/trx/trx0undo.cc:1251

#8  0x00007f20ecaed0c4 in trx_undo_insert_cleanup (trx=0x3422ca8) at /mariadb/10.0/storage/innobase/trx/trx0undo.cc:1990

#9  0x00007f20ecae464d in trx_cleanup_at_db_startup (trx=0x3422ca8) at /mariadb/10.0/storage/innobase/trx/trx0trx.cc:1426

#10 0x00007f20ecad63d1 in trx_rollback_resurrected (trx=0x3422ca8, all=0x7ffea6e74408) at /mariadb/10.0/storage/innobase/trx/trx0roll.cc:679

2018-01-18 15:41:49 139918570912896 [Note] InnoDB: Cleaning up trx with id 0x507

mysqld: /mariadb/10.2/storage/innobase/mtr/mtr0mtr.cc:570: void mtr_t::commit(): Assertion `!srv_read_only_mode || m_impl.m_log_mode == MTR_LOG_NO_REDO' failed.

…

mtr/mtr0mtr.cc:572(mtr_t::commit())[0x1b4a8d6]

trx/trx0undo.cc:1111(trx_undo_seg_free(trx_undo_t const*, bool))[0x1f3b877]

trx/trx0undo.cc:1796(trx_undo_commit_cleanup(trx_undo_t*, bool))[0x1f3b018]

trx/trx0trx.cc:2009(trx_cleanup_at_db_startup(trx_t*))[0x1f0cd1e]

trx/trx0roll.cc:749(trx_rollback_resurrected(trx_t*, unsigned long*))[0x1ee5a85]