!446 init进程收到子进程退出信号后，调用fork重新拉起进程，会导致系统卡死

Merge pull request !446 from zhangfanfan2/master

arch/arm/arm/src/los_hw.c

@@ -105,7 +105,15 @@ LITE_OS_SEC_TEXT_INIT VOID *OsTaskStackInit(UINT32 taskID, UINT32 stackSize, VOI
 
 LITE_OS_SEC_TEXT VOID OsUserCloneParentStack(VOID *childStack, UINTPTR parentTopOfStack, UINT32 parentStackSize)
 {
-    VOID *cloneStack = (VOID *)(((UINTPTR)parentTopOfStack + parentStackSize) - sizeof(TaskContext));
+    LosTaskCB *task = OsCurrTaskGet();
+    sig_cb *sigcb = &task->sig;
+    VOID *cloneStack = NULL;
+
+    if (sigcb->sigContext != NULL) {
+        cloneStack = (VOID *)((UINTPTR)sigcb->sigContext - sizeof(TaskContext));
+    } else {
+        cloneStack = (VOID *)(((UINTPTR)parentTopOfStack + parentStackSize) - sizeof(TaskContext));
+    }
 
     (VOID)memcpy_s(childStack, sizeof(TaskContext), cloneStack, sizeof(TaskContext));
     ((TaskContext *)childStack)->R0 = 0;

kernel/base/ipc/los_signal.c

@@ -678,6 +678,7 @@ VOID *OsRestorSignalContext(VOID *sp)
 
     LosProcessCB *process = OsCurrProcessGet();
     VOID *saveContext = sigcb->sigContext;
+    sigcb->sigContext = NULL;
     sigcb->count--;
     process->sigShare = 0;
     OsProcessExitCodeSignalClear(process);