Drush pm-update failed with drupal_wiki-7.x-1.2

I ran drush pm-update, but the update stuck on drupal_wiki, claiming that it cannot find the module directory. Afterwards, I run drush dl drupal_wiki and it suddenly complained that the directory already exists. After overwriting with the latest version, the problem stopped occurring.

Code updates will be made to the following projects: Wiki installation profile [drupal_wiki-7.x-1.2]

Note: A backup of your project will be stored to backups directory if it is not managed by a supported version control system.
Note: If you have made any modifications to any file that belongs to one of these projects, you will have to migrate those modifications after updating.
Do you really want to continue with the update process? (y/n): y
The drupal_wiki directory could not be found within the modules      [error]
directory at
/site_codebase/drupal7wiki/profiles/drupal_wiki,
perhaps the project is enabled but has been deleted from disk.
wizard@lnv-3209:/site_codebase/drupal7wiki/sites/default$ drush pm-update

drush dl drupal_wiki
Install location /site_codebase/drupal7wiki/profiles/drupal_wiki already exists. Do you want to overwrite it? (y/n): y
Project drupal_wiki (7.x-1.2) downloaded to                          [success]
/site_codebase/drupal7wiki/profiles/drupal_wiki.
Project drupal_wiki contains:                                        [success]
 - 1 profile: drupal_wiki
 - 30 modules: features, flexifilter, pathauto,
freelinking_prepopulate, freelinking, strongarm, diff, edit_section,
wiki_custom, extlink, prepopulate, token, footnotes_wysiwyg,
footnotes, footnotes_views, wysiwyg, page_manager, stylizer,
views_content, ctools_access_ruleset, ctools_ajax_sample,
ctools_custom_content, ctools_plugin_example, bulk_export, ctools,
talk, wikitools, admin_devel, admin_menu_toolbar, admin_menu

I am not sure if this is a problem of this profile, or of drush. If so, please move accordingly