WSOD for logged users after upgrading some module I have updated the following modules on my website:

ctools
context
devel
ds
libraries
metatag
pathologic
rel_to_abs
variable
webform  

After the upgrade whenever I log in, I am not able to access any page (not just the administration area).
Anonymous users have no problems.
Downloding the whole website and installing it locally with the backup before the update, everything works fine. 
I have enabled debug logs and all possibile error reporting options, but I have no error or warning of any kind.
I have increased the memory limit, clean every cache and run the registry rebuild via php.
I have no ssh access to the host, so I cannot run any remote debugging.
Can someone point me out to a possibile solution?
go into you database, set the status to 0 on the rows for each of the modules you mentioned. Reinstall each module one by one to find the problem module.  

you could also try adding this to the top of index.php (remember to remove it later)

ini_set('display_errors',1);
ini_set('display_startup_errors',1);
error_reporting(-1);