Changed the VM's hardware exception to return if not in manged code. For DAC's hardware exception handling, add

hardware exception holder used to determine if a C++ exception should be thrown for a hardware exception. Cleaned
up PAL initialization interactions between the debugger modules (PAL_InitializeDLL) and coreclr (PAL_InitializeCoreCLR).

14 files changed, 198 insertions, 142 deletions

diff --git a/dac.cmake b/dac.cmake
index 3440679681..bfa9d5241d 100644
--- a/dac.cmake
+++ b/dac.cmake
@@ -1,6 +1,7 @@
 # Contains the dac build specific definitions. Included by the leaf dac cmake files.
 
 add_definitions(-DDACCESS_COMPILE)
+add_definitions(-DFEATURE_ENABLE_HARDWARE_EXCEPTIONS)
 if(WIN32)
     remove_definitions(-DPROFILING_SUPPORTED)
     add_definitions(-DPROFILING_SUPPORTED_DATA)
diff --git a/src/debug/daccess/daccess.cpp b/src/debug/daccess/daccess.cpp
index 5da6aa8029..bc0d8fc742 100644
--- a/src/debug/daccess/daccess.cpp
+++ b/src/debug/daccess/daccess.cpp
@@ -37,15 +37,6 @@ HINSTANCE g_thisModule;
 
 extern VOID STDMETHODCALLTYPE TLS_FreeMasterSlotIndex();
 
-#ifdef FEATURE_PAL
-
-VOID PALAPI HandleHardwareException(PAL_SEHException* ex)
-{
-    throw *ex;
-}
-
-#endif // FEATURE_PAL
-
 EXTERN_C BOOL WINAPI
 DllMain(HANDLE instance, DWORD reason, LPVOID reserved)
 {
@@ -73,8 +64,6 @@ DllMain(HANDLE instance, DWORD reason, LPVOID reserved)
         {
             return FALSE;
         }
-        // Register handler of hardware exceptions like null reference in PAL
-        PAL_SetHardwareExceptionHandler(HandleHardwareException);
 #endif
         InitializeCriticalSection(&g_dacCritSec);
 
diff --git a/src/debug/ee/debugger.cpp b/src/debug/ee/debugger.cpp
index bf6b6bdc83..87cccf8653 100644
--- a/src/debug/ee/debugger.cpp
+++ b/src/debug/ee/debugger.cpp
@@ -1996,6 +1996,9 @@ HRESULT Debugger::Startup(void)
 
     DebuggerLockHolder dbgLockHolder(this);
 
+#ifdef FEATURE_PAL
+    DacGlobals::Initialize();
+#endif
 
     // Stubs in Stacktraces are always enabled.
     g_EnableSIS = true;
@@ -2545,6 +2548,10 @@ void Debugger::StopDebugger(void)
     }
     CONTRACTL_END;
    
+#ifdef FEATURE_PAL
+    PAL_CleanupDacTableAddress();
+#endif
+
     // Leak almost everything on process exit. The OS will clean it up anyways and trying to 
     // clean it up ourselves is just one more place we may AV / deadlock.
 
diff --git a/src/dlls/mscoree/mscoree.cpp b/src/dlls/mscoree/mscoree.cpp
index 3f207b565d..2c78e7db5b 100644
--- a/src/dlls/mscoree/mscoree.cpp
+++ b/src/dlls/mscoree/mscoree.cpp
@@ -180,9 +180,6 @@ BOOL WINAPI DllMain(HANDLE hInstance, DWORD dwReason, LPVOID lpReserved)
             // If buffer is overrun, it is possible the saved callback has been trashed.
             // The callback is unsafe.
             //SetBufferOverrunHandler();
-#ifdef FEATURE_PAL
-            DacGlobals::Initialize();
-#endif
             if (!EEDllMain((HINSTANCE)hInstance, dwReason, lpReserved))
             {
                 return FALSE;
@@ -196,9 +193,6 @@ BOOL WINAPI DllMain(HANDLE hInstance, DWORD dwReason, LPVOID lpReserved)
 
     case DLL_PROCESS_DETACH:
         {
-#ifdef FEATURE_PAL
-            PAL_CleanupDacTableAddress();
-#endif
             EEDllMain((HINSTANCE)hInstance, dwReason, lpReserved);
 
 #ifdef FEATURE_MERGE_JIT_AND_ENGINE
diff --git a/src/pal/inc/pal.h b/src/pal/inc/pal.h
index e2aff4e28c..ca8856c4ec 100644
--- a/src/pal/inc/pal.h
+++ b/src/pal/inc/pal.h
@@ -600,12 +600,6 @@ PAL_CleanupDacTableAddress(
     );
 
 
-PALIMPORT
-BOOL
-PALAPI
-PAL_RegisterMacEHPort();
-
-
 /******************* winuser.h Entrypoints *******************************/
 
 PALIMPORT
@@ -5849,18 +5843,18 @@ public:
 class PAL_EnterHolder {
 public:
     // using constructor to suppress the "unused variable" warnings
-    PAL_EnterHolder(){}
+    PAL_EnterHolder() {}
 };
 class PAL_LeaveHolder {
 public:
     // using constructor to suppress the "unused variable" warnings
-    PAL_LeaveHolder(){}
+    PAL_LeaveHolder() {}
 };
 #endif // __cplusplus
 
 #endif // FEATURE_PAL_SXS
 
-#if FEATURE_PAL_SXS
+#ifdef __cplusplus
 
 #include "pal_unwind.h"
 
@@ -5889,8 +5883,6 @@ typedef EXCEPTION_DISPOSITION (*PFN_PAL_EXCEPTION_FILTER)(
     PAL_DISPATCHER_CONTEXT *DispatcherContext,
     void *pvParam);
 
-#ifdef __cplusplus
-
 struct PAL_SEHException
 {
 public:
@@ -5916,16 +5908,34 @@ typedef VOID (PALAPI *PHARDWARE_EXCEPTION_HANDLER)(PAL_SEHException* ex);
 PALIMPORT
 VOID
 PALAPI
-PAL_SetHardwareExceptionHandler(IN PHARDWARE_EXCEPTION_HANDLER handler);
+PAL_SetHardwareExceptionHandler(
+    IN PHARDWARE_EXCEPTION_HANDLER exceptionHandler);
 
-#endif // __cplusplus
+class PAL_CatchHardwareExceptionHolder
+{
+public:
+    PAL_CatchHardwareExceptionHolder();
+
+    ~PAL_CatchHardwareExceptionHolder();
+
+    static bool IsEnabled();
+};
+
+#ifdef FEATURE_ENABLE_HARDWARE_EXCEPTIONS
+#define HardwareExceptionHolder PAL_CatchHardwareExceptionHolder __catchHardwareException;
+#else
+#define HardwareExceptionHolder
+#endif // FEATURE_ENABLE_HARDWARE_EXCEPTIONS
+
+#ifdef FEATURE_PAL_SXS
 
 // Start of a try block for exceptions raised by RaiseException
 #define PAL_TRY(__ParamType, __paramDef, __paramRef)                            \
 {                                                                               \
     __ParamType __param = __paramRef;                                           \
     auto tryBlock = [](__ParamType __paramDef)                                  \
-    {
+    {                                                                           \
+        HardwareExceptionHolder
 
 // Start of an exception handler. If an exception raised by the RaiseException 
 // occurs in the try block and the disposition is EXCEPTION_EXECUTE_HANDLER, 
@@ -5949,7 +5959,6 @@ PAL_SetHardwareExceptionHandler(IN PHARDWARE_EXCEPTION_HANDLER handler);
             throw;                                                              \
         }
 
-
 // Start of an exception handler. It works the same way as the PAL_EXCEPT except
 // that the disposition is obtained by calling the specified filter.
 #define PAL_EXCEPT_FILTER(filter) PAL_EXCEPT(filter(&ex.ExceptionPointers, __param))
@@ -5984,7 +5993,7 @@ PAL_SetHardwareExceptionHandler(IN PHARDWARE_EXCEPTION_HANDLER handler);
 
 #define PAL_CPP_THROW(type, obj) { throw obj; }
 #define PAL_CPP_RETHROW { throw; }
-#define PAL_CPP_TRY                     try {
+#define PAL_CPP_TRY                     try { HardwareExceptionHolder
 #define PAL_CPP_CATCH_EXCEPTION(ident)  } catch (Exception *ident) { PAL_Reenter(PAL_BoundaryBottom);
 #define PAL_CPP_CATCH_EXCEPTION_NOARG   } catch (Exception *) { PAL_Reenter(PAL_BoundaryBottom);
 #define PAL_CPP_CATCH_DERIVED(type, ident) } catch (type *ident) { PAL_Reenter(PAL_BoundaryBottom);
@@ -6005,18 +6014,24 @@ PAL_SetHardwareExceptionHandler(IN PHARDWARE_EXCEPTION_HANDLER handler);
     {                                                                   \
         ParamType __param = paramRef;                                   \
         ParamType paramDef; paramDef = __param;                         \
-        try {
+        try {                                                           \
+            HardwareExceptionHolder
+
 #define PAL_TRY_FOR_DLLMAIN(ParamType, paramDef, paramRef, _reason)     \
     {                                                                   \
         ParamType __param = paramRef;                                   \
         ParamType paramDef; paramDef = __param;                         \
-        try {
+        try {                                                           \
+            HardwareExceptionHolder
+
 #define PAL_ENDTRY                                                      \
         }                                                               \
     }
 
 #endif // FEATURE_PAL_SXS
 
+#endif // __cplusplus
+
 #define EXCEPTION_CONTINUE_SEARCH   0
 #define EXCEPTION_EXECUTE_HANDLER   1
 #define EXCEPTION_CONTINUE_EXECUTION -1
diff --git a/src/pal/src/exception/machexception.cpp b/src/pal/src/exception/machexception.cpp
index 33ed24a68a..7d31f76e4f 100644
--- a/src/pal/src/exception/machexception.cpp
+++ b/src/pal/src/exception/machexception.cpp
@@ -532,20 +532,11 @@ void PAL_DispatchException(DWORD64 dwRDI, DWORD64 dwRSI, DWORD64 dwRDX, DWORD64
     }
 #endif // FEATURE_PAL_SXS
 
-    if (g_hardwareExceptionHandler != NULL)
-    {
-        PAL_SEHException exception(pExRecord, pContext);
-
-        g_hardwareExceptionHandler(&exception);
-
-        ASSERT("HandleHardwareException has returned, it should not.\n");
-    }
-    else
-    {
-        ASSERT("Unhandled hardware exception\n");
-    }
+    EXCEPTION_POINTERS pointers;
+    pointers.ExceptionRecord = pExRecord;
+    pointers.ContextRecord = pContext;
 
-    ExitProcess(pExRecord->ExceptionCode);
+    SEHProcessException(&pointers);
 }
 
 #if defined(_X86_) || defined(_AMD64_)
diff --git a/src/pal/src/exception/seh.cpp b/src/pal/src/exception/seh.cpp
index e6f7b7aa63..4091914603 100644
--- a/src/pal/src/exception/seh.cpp
+++ b/src/pal/src/exception/seh.cpp
@@ -55,6 +55,17 @@ SET_DEFAULT_DEBUG_CHANNEL(EXCEPT);
 /* Bit 28 of exception codes is reserved. */
 const UINT RESERVED_SEH_BIT = 0x800000;
 
+/* Internal variables definitions **********************************************/
+
+PHARDWARE_EXCEPTION_HANDLER g_hardwareExceptionHandler = NULL;
+
+#ifdef __llvm__
+__thread 
+#else // __llvm__
+__declspec(thread)
+#endif // !__llvm__
+int t_holderCount = 0;
+
 /* Internal function declarations *********************************************/
 
 BOOL SEHInitializeConsole();
@@ -81,7 +92,8 @@ Return value :
     TRUE  if SEH support initialization succeeded
     FALSE otherwise
 --*/
-BOOL SEHInitialize (CPalThread *pthrCurrent, DWORD flags)
+BOOL 
+SEHInitialize (CPalThread *pthrCurrent, DWORD flags)
 {
     BOOL bRet = FALSE;
 
@@ -124,7 +136,8 @@ Parameters :
     (no return value)
     
 --*/
-void SEHCleanup (DWORD flags)
+VOID 
+SEHCleanup(DWORD flags)
 {
     TRACE("Cleaning up SEH\n");
 
@@ -135,23 +148,59 @@ void SEHCleanup (DWORD flags)
 #endif
 }
 
-PHARDWARE_EXCEPTION_HANDLER g_hardwareExceptionHandler = NULL;
+/*++
+Function:
+    PAL_SetHardwareExceptionHandler
 
+    Register a hardware exception handler.
+
+Parameters:
+    handler - exception handler
+
+Return value:
+    None
+--*/
 VOID
 PALAPI 
-PAL_SetHardwareExceptionHandler(PHARDWARE_EXCEPTION_HANDLER handler)
+PAL_SetHardwareExceptionHandler(
+    IN PHARDWARE_EXCEPTION_HANDLER exceptionHandler)
+
 {
-    g_hardwareExceptionHandler = handler;
+    g_hardwareExceptionHandler = exceptionHandler;
 }
 
-#ifdef FEATURE_PAL_SXS
-BOOL
-PALAPI
-PAL_RegisterMacEHPort()
+/*++
+Function:
+    SEHProcessException
+
+    Build the PAL exception and sent it to any handler registered.
+
+Parameters:
+    PEXCEPTION_POINTERS pointers
+
+Return value:
+    Does not return
+--*/
+PAL_NORETURN
+VOID
+SEHProcessException(PEXCEPTION_POINTERS pointers)
 {
-    return SEHEnable(InternalGetCurrentThread()) == ERROR_SUCCESS;
-}
+    PAL_SEHException exception(pointers->ExceptionRecord, pointers->ContextRecord);
 
+    if (g_hardwareExceptionHandler != NULL)
+    {
+        g_hardwareExceptionHandler(&exception);
+    }
+
+    if (PAL_CatchHardwareExceptionHolder::IsEnabled())
+    {
+        throw exception;
+    }
+
+    ASSERT("Unhandled hardware exception %08x\n", pointers->ExceptionRecord->ExceptionCode);
+
+    ExitProcess(pointers->ExceptionRecord->ExceptionCode);
+}
 
 /*++
 Function :
@@ -206,6 +255,26 @@ PAL_ERROR SEHDisable(CPalThread *pthrCurrent)
 #error not yet implemented
 #endif // HAVE_MACH_EXCEPTIONS
 }
-#endif // FEATURE_PAL_SXS
+
+/*++
+
+PAL_HandlerExceptionHolder implementation
+
+--*/
+
+PAL_CatchHardwareExceptionHolder::PAL_CatchHardwareExceptionHolder()
+{
+    ++t_holderCount;
+}
+
+PAL_CatchHardwareExceptionHolder::~PAL_CatchHardwareExceptionHolder()
+{
+    --t_holderCount;
+}
+
+bool PAL_CatchHardwareExceptionHolder::IsEnabled()
+{
+    return t_holderCount > 0;
+}
 
 #include "seh-unwind.cpp"
diff --git a/src/pal/src/exception/signal.cpp b/src/pal/src/exception/signal.cpp
index 4a90a55832..8e5f52825c 100644
--- a/src/pal/src/exception/signal.cpp
+++ b/src/pal/src/exception/signal.cpp
@@ -132,6 +132,10 @@ void SEHInitializeSignals(DWORD flags)
     handle_signal(SIGFPE,    sigfpe_handler);
     handle_signal(SIGBUS,    sigbus_handler);
     handle_signal(SIGSEGV,   sigsegv_handler);
+#if USE_SIGNALS_FOR_THREAD_SUSPENSION
+    handle_signal(SIGUSR1,   suspend_handler);
+    handle_signal(SIGUSR2,   resume_handler);
+#endif
 
     if (flags & PAL_INITIALIZE_ALL_SIGNALS)
     {
@@ -160,10 +164,6 @@ void SEHInitializeSignals(DWORD flags)
 #ifdef SIGINFO
         handle_signal(SIGINFO,   NULL);
 #endif  // SIGINFO
-#if USE_SIGNALS_FOR_THREAD_SUSPENSION
-        handle_signal(SIGUSR1,   suspend_handler);
-        handle_signal(SIGUSR2,   resume_handler);
-#endif
         
         /* The default action for SIGPIPE is process termination.
            Since SIGPIPE can be signaled when trying to write on a socket for which
@@ -548,25 +548,13 @@ static void common_signal_handler(PEXCEPTION_POINTERS pointers, int code,
 
     /* Unmask signal so we can receive it again */
     sigemptyset(&signal_set);
-    sigaddset(&signal_set,code);
-    if(-1 == sigprocmask(SIG_UNBLOCK,&signal_set,NULL))
+    sigaddset(&signal_set, code);
+    if(-1 == sigprocmask(SIG_UNBLOCK, &signal_set, NULL))
     {
-        ASSERT("sigprocmask failed; error is %d (%s)\n",errno, strerror(errno));
+        ASSERT("sigprocmask failed; error is %d (%s)\n", errno, strerror(errno));
     } 
 
-    if (g_hardwareExceptionHandler != NULL)
-    {
-        PAL_SEHException exception(pointers->ExceptionRecord, pointers->ContextRecord);
-
-        g_hardwareExceptionHandler(&exception);
-        ASSERT("HardwareExceptionHandler has returned, it should not.");
-    }
-    else
-    {
-        ASSERT("Unhandled hardware exception\n");
-    }
-
-    ExitProcess(pointers->ExceptionRecord->ExceptionCode);
+    SEHProcessException(pointers);
 }
 
 /*++
diff --git a/src/pal/src/include/pal/module.h b/src/pal/src/include/pal/module.h
index 0e65766468..803ca36dc7 100644
--- a/src/pal/src/include/pal/module.h
+++ b/src/pal/src/include/pal/module.h
@@ -225,13 +225,13 @@ int LOADGetLibRotorPalSoFileName(LPSTR pszBuf);
     mscorwks).
 
 Parameters:
-    void
+    Core CLR path
 
 Return value:
     TRUE if successful
     FALSE if failure
 --*/
-BOOL LOADInitCoreCLRModules();
+BOOL LOADInitCoreCLRModules(const char *szCoreCLRPath);
 
 #if defined(CORECLR) && defined(__APPLE__)
 // Abstract the API used to load and query for functions in the CoreCLR binary to make it easier to change the
diff --git a/src/pal/src/include/pal/seh.hpp b/src/pal/src/include/pal/seh.hpp
index bc596bace9..399a417ea7 100644
--- a/src/pal/src/include/pal/seh.hpp
+++ b/src/pal/src/include/pal/seh.hpp
@@ -25,8 +25,6 @@ Abstract:
 #include "pal/palinternal.h"
 #include "pal/corunix.hpp"
 
-extern PHARDWARE_EXCEPTION_HANDLER g_hardwareExceptionHandler;
-
 // Uncomment this define to turn off the signal handling thread.
 // #define DO_NOT_USE_SIGNAL_HANDLING_THREAD
 
@@ -45,7 +43,8 @@ Return value:
     FALSE otherwise
 
 --*/
-BOOL SEHInitialize(CorUnix::CPalThread *pthrCurrent, DWORD flags);
+BOOL 
+SEHInitialize(CorUnix::CPalThread *pthrCurrent, DWORD flags);
 
 /*++
 Function :
@@ -58,7 +57,24 @@ Parameters:
 
     (no return value)
 --*/
-void SEHCleanup(DWORD flags);
+VOID 
+SEHCleanup(DWORD flags);
+
+/*++
+Function:
+    SEHProcessException
+
+    Build the PAL exception and sent it to any handler registered.
+
+Parameters:
+    None
+
+Return value:
+    Does not return
+--*/
+PAL_NORETURN
+VOID 
+SEHProcessException(PEXCEPTION_POINTERS pointers);
 
 /*++
 Function :
diff --git a/src/pal/src/init/pal.cpp b/src/pal/src/init/pal.cpp
index 554cde6c62..7135e0c5c0 100644
--- a/src/pal/src/init/pal.cpp
+++ b/src/pal/src/init/pal.cpp
@@ -658,12 +658,14 @@ PAL_InitializeCoreCLR(
     int result = PAL_Initialize(1, &szExePath);
 #endif // __APPLE__
     if (result != 0)
+    {
         return GetLastError();
+    }
 
     // Now that the PAL is initialized it's safe to call the initialization methods for the code that used to
     // be dynamically loaded libraries but is now statically linked into CoreCLR just like the PAL, i.e. the
     // PAL RT and mscorwks.
-    if (!LOADInitCoreCLRModules())
+    if (!LOADInitCoreCLRModules(g_szCoreCLRPath))
     {
         return ERROR_DLL_INIT_FAILED;
     }
diff --git a/src/pal/src/loader/module.cpp b/src/pal/src/loader/module.cpp
index 80bc1c17a1..45b217b724 100644
--- a/src/pal/src/loader/module.cpp
+++ b/src/pal/src/loader/module.cpp
@@ -91,11 +91,6 @@ CRITICAL_SECTION module_critsec;
 MODSTRUCT exe_module; /* always the first, in the in-load-order list */
 MODSTRUCT pal_module; /* always the second, in the in-load-order list */
 
-PDLLMAIN g_pRuntimeDllMain = NULL;
-// Use the g_szCoreCLRPath global to determine whether we're really part of CoreCLR or just a standalone PAL
-// linked into some utility.
-extern char g_szCoreCLRPath[MAX_PATH];
-
 /* static function declarations ***********************************************/
 
 static BOOL LOADValidateModule(MODSTRUCT *module);
@@ -634,6 +629,8 @@ GetModuleFileNameW(
 
     LockModuleList();
 
+    wcscpy_s(lpFileName, nSize, W(""));
+
     if(hModule && !LOADValidateModule((MODSTRUCT *)hModule))
     {
         TRACE("Can't find name for invalid module handle %p\n", hModule);
@@ -644,7 +641,7 @@ GetModuleFileNameW(
 
     if(!wide_name)
     {
-        ASSERT("Can't find name for valid module handle %p\n", hModule);
+        TRACE("Can't find name for valid module handle %p\n", hModule);
         SetLastError(ERROR_INTERNAL_ERROR);
         goto done;
     }
@@ -869,8 +866,6 @@ Notes :
 extern "C"
 BOOL LOADInitializeModules(LPWSTR exe_name)
 {
-    LPWSTR  lpwstr = NULL;
-
 #if RETURNS_NEW_HANDLES_ON_REPEAT_DLOPEN
     LPSTR   pszExeName = NULL;
     CPalThread *pThread = NULL;
@@ -889,55 +884,27 @@ BOOL LOADInitializeModules(LPWSTR exe_name)
 
     /* initialize module for main executable */
     TRACE("Initializing module for main executable\n");
-    exe_module.self=(HMODULE)&exe_module;
-    exe_module.dl_handle=dlopen(NULL, RTLD_LAZY);
+    exe_module.self = (HMODULE)&exe_module;
+    exe_module.dl_handle = dlopen(NULL, RTLD_LAZY);
     if(!exe_module.dl_handle)
     {
         ASSERT("Main executable module will be broken : dlopen(NULL) failed. "
              "dlerror message is \"%s\" \n", dlerror());
     }
     exe_module.lib_name = exe_name;
-    exe_module.refcount=-1;
-    exe_module.next=&pal_module;
-    exe_module.prev=&pal_module;
+    exe_module.refcount = -1;
+    exe_module.next = &pal_module;
+    exe_module.prev = &pal_module;
     exe_module.pDllMain = NULL;
     exe_module.ThreadLibCalls = TRUE;
     
     TRACE("Initializing module for PAL library\n");
-    pal_module.self=(HANDLE)&pal_module;
-
-    if (g_szCoreCLRPath[0] == '\0')
-    {
-        pal_module.lib_name=NULL;
-        pal_module.dl_handle=NULL;
-    } else
-    {
-        TRACE("PAL library is %s\n", g_szCoreCLRPath);
-        lpwstr = UTIL_MBToWC_Alloc(g_szCoreCLRPath, -1);
-        if(NULL == lpwstr)
-        {
-            ERROR("MBToWC failure, unable to save full name of PAL module\n");
-            goto Done;
-        }
-        pal_module.lib_name=lpwstr;
-        pal_module.dl_handle=dlopen(g_szCoreCLRPath, RTLD_LAZY);
-
-        if(pal_module.dl_handle)
-        {
-            g_pRuntimeDllMain = (PDLLMAIN)dlsym(pal_module.dl_handle, "CoreDllMain");
-        }
-        else
-        {
-#if !defined(__hppa__)
-            ASSERT("PAL module will be broken : dlopen(%s) failed. dlerror "
-                 "message is \"%s\"\n ", g_szCoreCLRPath, dlerror());
-#endif
-        }
-    }
-
-    pal_module.refcount=-1;
-    pal_module.next=&exe_module;
-    pal_module.prev=&exe_module;
+    pal_module.self = (HANDLE)&pal_module;
+    pal_module.lib_name = NULL;
+    pal_module.dl_handle = NULL;
+    pal_module.refcount= - 1;
+    pal_module.next = &exe_module;
+    pal_module.prev = &exe_module;
     pal_module.pDllMain = NULL;
     pal_module.ThreadLibCalls = TRUE;
 
@@ -1905,15 +1872,32 @@ Done:
     mscorwks).
 
 Parameters:
-    void
+    Core CLR path
 
 Return value:
     TRUE if successful
     FALSE if failure
 --*/
-BOOL LOADInitCoreCLRModules()
+BOOL LOADInitCoreCLRModules(
+    const char *szCoreCLRPath)
 {
-    return g_pRuntimeDllMain((HMODULE)&pal_module, DLL_PROCESS_ATTACH, NULL);
+    TRACE("PAL library is %s\n", szCoreCLRPath);
+    LPWSTR lpwstr = UTIL_MBToWC_Alloc(szCoreCLRPath, -1);
+    if(!lpwstr)
+    {
+        ERROR("MBToWC failure, unable to save full name of PAL module\n");
+        return FALSE;
+    }
+    pal_module.lib_name = lpwstr;
+    pal_module.dl_handle = dlopen(szCoreCLRPath, RTLD_LAZY);
+    if(!pal_module.dl_handle)
+    {
+        ERROR("PAL module will be broken : dlopen(%s) failed. dlerror message is \"%s\"\n ", 
+            szCoreCLRPath, dlerror());
+        return FALSE;
+    }
+    PDLLMAIN pRuntimeDllMain = (PDLLMAIN)dlsym(pal_module.dl_handle, "CoreDllMain");
+    return pRuntimeDllMain((HMODULE)&pal_module, DLL_PROCESS_ATTACH, NULL);
 }
 
 // Get base address of the module containing a given symbol 
diff --git a/src/pal/src/misc/miscpalapi.cpp b/src/pal/src/misc/miscpalapi.cpp
index a9d11c6cd2..88e285929a 100644
--- a/src/pal/src/misc/miscpalapi.cpp
+++ b/src/pal/src/misc/miscpalapi.cpp
@@ -37,8 +37,6 @@ Revision History:
 #include <mach-o/dyld.h>
 #endif // __APPLE__
 
-extern char g_szCoreCLRPath[MAX_PATH];
-
 SET_DEFAULT_DEBUG_CHANNEL(MISC);
 
 static const char RANDOM_DEVICE_NAME[] ="/dev/random";
@@ -71,6 +69,11 @@ PAL_GetPALDirectoryW( OUT LPWSTR lpDirectoryName, IN UINT cchDirectoryName )
     ENTRY( "PAL_GetPALDirectoryW( %p, %d )\n", lpDirectoryName, cchDirectoryName );
 
     lpFullPathAndName = pal_module.lib_name;
+    if (lpFullPathAndName == NULL)
+    {
+        SetLastError(ERROR_INTERNAL_ERROR);
+        goto EXIT;
+    }
     lpEndPoint = PAL_wcsrchr( lpFullPathAndName, '/' );
     if ( lpEndPoint )
     {
diff --git a/src/vm/exceptionhandling.cpp b/src/vm/exceptionhandling.cpp
index c3399e340a..2fe593c804 100644
--- a/src/vm/exceptionhandling.cpp
+++ b/src/vm/exceptionhandling.cpp
@@ -4985,8 +4985,6 @@ VOID PALAPI HandleHardwareException(PAL_SEHException* ex)
             }
             UNREACHABLE();
         }
-
-        _ASSERTE(!"HandleHardwareException: Hardware exception happened out of managed code");        
     }
     else 
     {
@@ -5015,7 +5013,6 @@ VOID PALAPI HandleHardwareException(PAL_SEHException* ex)
             }
         }
     }
-    EEPOLICY_HANDLE_FATAL_ERROR(COR_E_EXECUTIONENGINE);
 }
 
 #endif // FEATURE_PAL