Comment 11 for bug 1874243

Ok, wrong thing I checked, so I see the issue. So on the 2020-03-10 with commit bf03e4f78 the "dmcrypt_dev = os.path.join("/dev", "mapper", dm_name)" line has been added to dm_crypt_handler() which is now crashing. As per the snippet above, in other places we are defaulting to using 'id' when 'dm_name' is not available, so I'd recommend doing the same here. Is there a reason for not following the same procedures in both places?