From 71aacd7ed8d1b89c5338f4f98201123c175a8024 Mon Sep 17 00:00:00 2001
From: Alexander Boettcher <alexander.boettcher@genode-labs.com>
Date: Fri, 30 Aug 2013 08:46:21 +0200
Subject: [PATCH] noux: first remove from list, then dissolve

Avoids deadlock - which is out of the list can't be found twice to be deleted.

Issue #485
---
 ports/src/noux/dataspace_registry.h    | 10 ++++------
 ports/src/noux/local_rm_service.h      | 13 ++++++++-----
 ports/src/noux/ram_session_component.h |  3 ++-
 ports/src/noux/rom_session_component.h | 10 ++++++----
 4 files changed, 20 insertions(+), 16 deletions(-)

diff --git a/ports/src/noux/dataspace_registry.h b/ports/src/noux/dataspace_registry.h
index 150e40d7ab..c98e26b7c0 100644
--- a/ports/src/noux/dataspace_registry.h
+++ b/ports/src/noux/dataspace_registry.h
@@ -124,11 +124,7 @@ namespace Noux {
 				 * created via 'Rm_dataspace_info::fork', are not handled by
 				 * those destructors. So we have to clean them up here.
 				 */
-				for (;;) {
-					Dataspace_info *info = _pool.first();
-					if (!info)
-						return;
-
+				while(Dataspace_info *info = _pool.first()) {
 					_pool.remove_locked(info);
 					destroy(env()->heap(), info);
 				}
@@ -172,8 +168,10 @@ namespace Noux {
 				return;
 			}
 
-			info->dissolve_users();
 			_ds_registry.remove(info);
+
+			info->dissolve_users();
+
 		}
 
 		Dataspace_capability fork(Ram_session_capability,
diff --git a/ports/src/noux/local_rm_service.h b/ports/src/noux/local_rm_service.h
index 7217c1b579..a90ad6727c 100644
--- a/ports/src/noux/local_rm_service.h
+++ b/ports/src/noux/local_rm_service.h
@@ -132,13 +132,16 @@ namespace Noux {
 
 				/* release dataspace info */
 				Dataspace_info *info = _ds_registry.lookup_info(ds_cap);
-				if (info) {
-					info->dissolve_users();
-					_ds_registry.remove(info);
-					destroy(env()->heap(), info);
-				} else {
+				if (!info) {
 					PWRN("Could not lookup dataspace info for local RM session");
+					return;
 				}
+
+				_ds_registry.remove(info);
+
+				info->dissolve_users();
+
+				destroy(env()->heap(), info);
 			}
 	};
 }
diff --git a/ports/src/noux/ram_session_component.h b/ports/src/noux/ram_session_component.h
index 38f7586072..2ea6e30a26 100644
--- a/ports/src/noux/ram_session_component.h
+++ b/ports/src/noux/ram_session_component.h
@@ -161,9 +161,10 @@ namespace Noux {
 					return;
 				}
 
+				_registry.remove(ds_info);
+
 				ds_info->dissolve_users();
 
-				_registry.remove(ds_info);
 				_list.remove(ds_info);
 				_used_quota -= ds_info->size();
 
diff --git a/ports/src/noux/rom_session_component.h b/ports/src/noux/rom_session_component.h
index 3d0756c605..9087877449 100644
--- a/ports/src/noux/rom_session_component.h
+++ b/ports/src/noux/rom_session_component.h
@@ -66,18 +66,20 @@ namespace Noux {
 			~Rom_session_component()
 			{
 				/*
-				 * Lookup and lock ds info instead of directly acccessing
+				 * Lookup and lock ds info instead of directly accessing
 				 * the '_ds_info' member.
 				 */
 				Object_pool<Dataspace_info>::Guard
 					info(_ds_registry.lookup_info(_ds_info.ds_cap()));
 
-				if (info)
-					info->dissolve_users();
-				else
+				if (!info) {
 					PERR("~Rom_session_component: unexpected !info");
+					return;
+				}
 
 				_ds_registry.remove(&_ds_info);
+
+				info->dissolve_users();
 			}