Crash recovery failure after the server is killed during innodb_encrypt_log startup

--source include/restart_mysqld.inc

exec $XTRABACKUP --defaults-file=$MYSQLTEST_VARDIR/my.cnf --backup --target-dir=$targetdir

2017-07-13 16:24:34 139729790940992 [Note] InnoDB: Starting crash recovery from checkpoint LSN=1637690

2017-07-13 16:24:34 139729790940992 [ERROR] InnoDB: Incorrect log record type:73

2017-07-13 16:24:34 139729790940992 [Warning] InnoDB: Log scan aborted at LSN 1637376

2017-07-13 16:24:34 139729790940992 [ERROR] InnoDB: Plugin initialization aborted with error Generic error

xtrabackup: innodb_init() returned 11 (Generic error).

bash-4.2$ ./mtr xb_file_key_management

Logging: ./mtr  xb_file_key_management

vardir: /home/a/spd/_depot/m-tar/10.2.7/mysql-test/var

Checking leftover processes...

Removing old var directory...

Creating var directory '/home/a/spd/_depot/m-tar/10.2.7/mysql-test/var'...

Checking supported features...

MariaDB Version 10.2.7-MariaDB

 - SSL connections supported

Collecting tests...

Installing system database...

==============================================================================

TEST                                      RESULT   TIME (ms) or COMMENT

--------------------------------------------------------------------------

worker[1] Using MTR_BUILD_THREAD 300, with reserved ports 16000..16019

mariabackup.xb_file_key_management       [ fail ]

        Test ended at 2017-07-13 16:26:36

CURRENT_TEST: mariabackup.xb_file_key_management

mysqltest: At line 26: exec of '/home/a/spd/_depot/m-tar/10.2.7/bin/mariabackup  --prepare --target-dir=/home/a/spd/_depot/m-tar/10.2.7/mysql-test/var/tmp/backup 2>&1' failed, error: 256, status: 1, errno: 11

Output from before failure:

/home/a/spd/_depot/m-tar/10.2.7/bin/mariabackup based on MariaDB server 10.2.7-MariaDB Linux (x86_64) 

xtrabackup: cd to /home/a/spd/_depot/m-tar/10.2.7/mysql-test/var/tmp/backup/

Loading encryption plugin

         Encryption plugin parameter :  '--file_key_management_encryption_algorithm=aes_cbc'

         Encryption plugin parameter :  '--file_key_management_filekey=FILE:/home/a/spd/_depot/m-tar/10.2.7/mysql-test/suite/mariabackup/filekeys-data.key'

         Encryption plugin parameter :  '--file_key_management_filename=/home/a/spd/_depot/m-tar/10.2.7/mysql-test/suite/mariabackup/filekeys-data.enc'

         Encryption plugin parameter :  '--prepare'

         Encryption plugin parameter :  '--target-dir=/home/a/spd/_depot/m-tar/10.2.7/mysql-test/var/tmp/backup'

xtrabackup: This target seems to be not prepared yet.

xtrabackup: using the following InnoDB configuration for recovery:

xtrabackup:   innodb_data_home_dir = .

xtrabackup:   innodb_data_file_path = ibdata1:12M:autoextend

xtrabackup:   innodb_log_group_home_dir = .

xtrabackup: Starting InnoDB instance for recovery.

xtrabackup: Using 104857600 bytes for buffer pool (set by --use-memory parameter)

2017-07-13 16:26:35 140656125790016 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins

2017-07-13 16:26:35 140656125790016 [Note] InnoDB: Uses event mutexes

2017-07-13 16:26:35 140656125790016 [Note] InnoDB: Compressed tables use zlib 1.2.3

2017-07-13 16:26:35 140656125790016 [Note] InnoDB: Number of pools: 1

2017-07-13 16:26:35 140656125790016 [Note] InnoDB: Using SSE2 crc32 instructions

2017-07-13 16:26:35 140656125790016 [Note] InnoDB: Initializing buffer pool, total size = 100M, instances = 1, chunk size = 100M

2017-07-13 16:26:35 140656125790016 [Note] InnoDB: Completed initialization of buffer pool

2017-07-13 16:26:35 140655682647808 [Note] InnoDB: If the mysqld execution user is authorized, page cleaner thread priority can be changed. See the man page of setpriority().

2017-07-13 16:26:35 140656125790016 [Note] InnoDB: Highest supported file format is Barracuda.

2017-07-13 16:26:35 140656125790016 [Note] InnoDB: Starting crash recovery from checkpoint LSN=1637690

2017-07-13 16:26:35 140656125790016 [ERROR] InnoDB: Incorrect log record type:104

2017-07-13 16:26:35 140656125790016 [Warning] InnoDB: Log scan aborted at LSN 1637376

2017-07-13 16:26:35 140656125790016 [ERROR] InnoDB: Plugin initialization aborted with error Generic error

xtrabackup: innodb_init() returned 11 (Generic error).

The result from queries just before the failure was:

CREATE TABLE t(c VARCHAR(10)) ENGINE INNODB encrypted=yes;

INSERT INTO t VALUES('foobar1');

# xtrabackup backup

NOT FOUND /foobar1/ in ib_logfile0

# expect NOT FOUND

INSERT INTO t VALUES('foobar2');

# xtrabackup prepare

 - saving '/home/a/spd/_depot/m-tar/10.2.7/mysql-test/var/log/mariabackup.xb_file_key_management/' to '/home/a/spd/_depot/m-tar/10.2.7/mysql-test/var/log/mariabackup.xb_file_key_management/'

--------------------------------------------------------------------------

The servers were restarted 0 times

Spent 0.000 of 8 seconds executing testcases

Failure: Failed 1/1 tests, 0.00% were successful.

Failing test(s): mariabackup.xb_file_key_management

The log files in var/log may give you some hint of what went wrong.

If you want to report this error, please read first the documentation

at http://dev.mysql.com/doc/mysql/en/mysql-test-suite.html

mysql-test-run: *** ERROR: there were failing test cases