when I am upgrade moodle 3.3 to 3.5 , I am also getting same error.
Fix:
in my case I set permission for 0777 in my lock folder then its working fine.
Re: Error Message after upgrade - The operation timed out while waiting for a lock
by Anandham K -
Number of replies: 1
In reply to Anandham K
Re: Error Message after upgrade - The operation timed out while waiting for a lock
by Swathy Prabhu -
The lockfiles in the lock subdirectory in the moodledata may have missing permissions, such as rw-r--r-- and owned by another user, such as root (!!)
The way I solved this problem is to change the ownership of the lock directory to www-data by the following command.
$ chown -R www-data:www-data /var/www/moodledata/lock
(Please note that the moodledata in my case is under /var/www)