如题： 修改mysql的数据文件之后，重新启动mysql服务，报无法创建测试文件的错误.文件的权限应该是没有问题的，不知道是否是apparmor之类的安全软件的问题。求助求助
------------------------ 文件夹权限 --------------------------
➜  ~ ls -l /media/doggy/D
总用量 20
drwx------ 2 root  root  16384 2月  13 11:43 lost+found
drwxrwxrwx 3 mysql mysql  4096 2月  13 13:11 mysql

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----------------------- 错误日志 -------------------------------
2月 13 13:53:12 doggy-home mysqld[6401]: mysqld: Can't change dir to '/media/doggy/D/mysql/' (Errcode: 13 - Permission denied)
2月 13 13:53:12 doggy-home mysqld[6401]: 2018-02-13T05:53:12.364511Z 0 [Warning] Changed limits: max_open_files: 1024 (requested 5000)
2月 13 13:53:12 doggy-home mysqld[6401]: 2018-02-13T05:53:12.364568Z 0 [Warning] Changed limits: table_open_cache: 431 (requested 2000)
2月 13 13:53:12 doggy-home mysqld[6401]: 2018-02-13T05:53:12.508077Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2月 13 13:53:12 doggy-home mysqld[6401]: 2018-02-13T05:53:12.508121Z 0 [Warning] Can't create test file /media/doggy/D/mysql/doggy-home.lower-test
2月 13 13:53:12 doggy-home mysqld[6401]: 2018-02-13T05:53:12.508142Z 0 [Note] /usr/sbin/mysqld (mysqld 5.7.18-1) starting as process 6401 ...
2月 13 13:53:12 doggy-home mysqld[6401]: 2018-02-13T05:53:12.509719Z 0 [Warning] Can't create test file /media/doggy/D/mysql/doggy-home.lower-test
2月 13 13:53:12 doggy-home mysqld[6401]: 2018-02-13T05:53:12.509729Z 0 [Warning] Can't create test file /media/doggy/D/mysql/doggy-home.lower-test
2月 13 13:53:12 doggy-home mysqld[6401]: 2018-02-13T05:53:12.509757Z 0 [ERROR] failed to set datadir to /media/doggy/D/mysql/
2月 13 13:53:12 doggy-home mysqld[6401]: 2018-02-13T05:53:12.509762Z 0 [ERROR] Aborting
2月 13 13:53:12 doggy-home mysqld[6401]: 2018-02-13T05:53:12.509770Z 0 [Note] Binlog end
2月 13 13:53:12 doggy-home mysqld[6401]: 2018-02-13T05:53:12.509805Z 0 [Note] /usr/sbin/mysqld: Shutdown complete
2月 13 13:53:12 doggy-home systemd[1]: mysql.service: Main process exited, code=exited, status=1/FAILURE


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