diff --git a/src/proxy.c b/src/proxy.c
index ae761ea..a537e0b 100644
--- a/src/proxy.c
+++ b/src/proxy.c
@@ -1940,9 +1940,12 @@
 	if (!px)
 		return 1;
 
+	/* Note: this lock is to make sure this doesn't change while another
+	 * thread is in srv_set_dyncookie().
+	 */
 	HA_SPIN_LOCK(PROXY_LOCK, &px->lock);
-
 	px->ck_opts |= PR_CK_DYNAMIC;
+	HA_SPIN_UNLOCK(PROXY_LOCK, &px->lock);
 
 	for (s = px->srv; s != NULL; s = s->next) {
 		HA_SPIN_LOCK(SERVER_LOCK, &s->lock);
@@ -1950,8 +1953,6 @@
 		HA_SPIN_UNLOCK(SERVER_LOCK, &s->lock);
 	}
 
-	HA_SPIN_UNLOCK(PROXY_LOCK, &px->lock);
-
 	return 1;
 }
 
@@ -1971,9 +1972,12 @@
 	if (!px)
 		return 1;
 
+	/* Note: this lock is to make sure this doesn't change while another
+	 * thread is in srv_set_dyncookie().
+	 */
 	HA_SPIN_LOCK(PROXY_LOCK, &px->lock);
-
 	px->ck_opts &= ~PR_CK_DYNAMIC;
+	HA_SPIN_UNLOCK(PROXY_LOCK, &px->lock);
 
 	for (s = px->srv; s != NULL; s = s->next) {
 		HA_SPIN_LOCK(SERVER_LOCK, &s->lock);
@@ -1984,8 +1988,6 @@
 		HA_SPIN_UNLOCK(SERVER_LOCK, &s->lock);
 	}
 
-	HA_SPIN_UNLOCK(PROXY_LOCK, &px->lock);
-
 	return 1;
 }
 
@@ -2021,10 +2023,13 @@
 		return 1;
 	}
 
+	/* Note: this lock is to make sure this doesn't change while another
+	 * thread is in srv_set_dyncookie().
+	 */
 	HA_SPIN_LOCK(PROXY_LOCK, &px->lock);
-
 	free(px->dyncookie_key);
 	px->dyncookie_key = newkey;
+	HA_SPIN_UNLOCK(PROXY_LOCK, &px->lock);
 
 	for (s = px->srv; s != NULL; s = s->next) {
 		HA_SPIN_LOCK(SERVER_LOCK, &s->lock);
@@ -2032,8 +2037,6 @@
 		HA_SPIN_UNLOCK(SERVER_LOCK, &s->lock);
 	}
 
-	HA_SPIN_UNLOCK(PROXY_LOCK, &px->lock);
-
 	return 1;
 }