[3.0] dec9098 Clear the pass oc flag bits earlier in the ban lurker

[Martin Blix Grydeland]

commit dec9098a2ac760d7ba4765a9a1a1091103b6eb05
Author: Martin Blix Grydeland <martin at varnish-software.com>
Date:   Wed Apr 9 11:28:43 2014 +0200

    Clear the pass oc flag bits earlier in the ban lurker
    
    The pass bits of the oc's flags wasn't cleared before or'ing the new
    pass on failing the busy object test in the ban lurker. This would
    cause the pass not to be matched later, making the lurker spin on the
    busy object.
    
    Fixes: #1470

diff --git a/bin/varnishd/cache_ban.c b/bin/varnishd/cache_ban.c
index 6062f98..4e4de57 100644
--- a/bin/varnishd/cache_ban.c
+++ b/bin/varnishd/cache_ban.c
@@ -844,6 +844,10 @@ ban_lurker_work(const struct sess *sp, unsigned pass)
 				continue;
 			}
 			/*
+			 * Clear this oc's pass bits.
+			 */
+			oc->flags &= ~OC_F_LURK;
+			/*
 			 * If the object is busy, we can't touch
 			 * it. Defer it to a later run.
 			 */
@@ -861,7 +865,6 @@ ban_lurker_work(const struct sess *sp, unsigned pass)
 			 */
 			AN(oc->refcnt);
 			oc->refcnt++;
-			oc->flags &= ~OC_F_LURK;
 			Lck_Unlock(&ban_mtx);
 			/*
 			 * Get the object and check it against all relevant bans