Description of problem:

we are getting a deadlock on SpmStart when SD is manually activated while SD is blocked from host (with iptables). 
because resource is not released host is stuck in contending and we are unable to squire SPM.  

Saggi checked and code change in commit 4d1dbcdd859be7a16ca0a276076b4a9f6ad5e7fa  "Fix lock release and reversed SPM logic"

self.lock should  be an RLOCK

Version-Release number of selected component (if applicable):

vdsm-4.9.3.2-0.fc16.x86_64

How reproducible:

100%

Steps to Reproduce:
1. create SD from 2 storage servers
2. block connectivity to 1 of the domains from host using iptables
3. after domain become inactive try to manually activate it
4. remove iptables block from host and try to activate domain again
  
Actual results:

deadlock in SpmStart, host will be stuck in contending and we cannot recover. 

Expected results:

we should be able to recover. 

Additional info: vdsm logs+ engine log