Ignore suspicious wake-up messages on OKL4

base-okl4/include/base/ipc_pager.h

@@ -77,6 +77,7 @@ namespace Genode {
 
 			Okl4::L4_MsgTag_t   _faulter_tag;   /* fault flags                    */
 			Okl4::L4_ThreadId_t _last;          /* faulted thread                 */
+			Okl4::L4_Word_t     _last_space;    /* space of faulted thread        */
 			Okl4::L4_Word_t     _fault_addr;    /* page-fault address             */
 			Okl4::L4_Word_t     _fault_ip;      /* instruction pointer of faulter */
 			Mapping             _reply_mapping; /* page-fault answer              */
@@ -148,6 +149,11 @@ namespace Genode {
 			 */
 			Native_thread_id last() const { return _last; }
 
+			/**
+			 * Return address space where the last page fault occurred
+			 */
+			unsigned long last_space() const { return _last_space; }
+
 			/**
 			 * Return badge for faulting thread
 			 *

base-okl4/src/base/ipc/pager.cc

@@ -108,6 +108,7 @@ void Ipc_pager::wait_for_fault()
 		if (verbose_page_fault)
 			print_page_fault(L4_Label(_faulter_tag), _fault_addr, _fault_ip, _last.raw);
 	}
+	_last_space = L4_SenderSpace().raw;
 }
 
 

base-okl4/src/base/pager/pager.cc

@@ -54,14 +54,16 @@ void Pager_activation_base::entry()
 
 		} else {
 
-			/* prevent threads outside of core to mess with our wake-up interface */
-//			enum { CORE_TASK_ID = 4 };
-//			if (pager.last() != CORE_TASK_ID) {
-
-#warning Check for messages from outside of core
-			if (0) {
-
-			} else {
+			/*
+			 * Prevent threads outside of core to mess with our wake-up
+			 * interface. This condition can trigger if a process gets
+			 * destroyed which triggered a page fault shortly before getting
+			 * killed. In this case, 'wait_for_fault()' returns (because of
+			 * the page fault delivery) but the pager-object lookup will fail
+			 * (because core removed the process already).
+			 */
+			enum { CORE_SPACE = 0 };
+			if (pager.last_space() == CORE_SPACE) {
 
 				/*
 				 * We got a request from one of cores region-manager sessions