diff --git a/LibOS/glibc-2.19.patch b/LibOS/glibc-2.19.patch
index 3aeec384..8fef9306 100644
--- a/LibOS/glibc-2.19.patch
+++ b/LibOS/glibc-2.19.patch
@@ -1804,19 +1804,17 @@ diff --git a/sysdeps/unix/sysv/linux/x86_64/syscall.S b/sysdeps/unix/sysv/linux/
 index 92c2f5b..e32ebb2 100644
 --- a/sysdeps/unix/sysv/linux/x86_64/syscall.S
 +++ b/sysdeps/unix/sysv/linux/x86_64/syscall.S
-@@ -31,10 +31,13 @@ ENTRY (syscall)
+@@ -31,10 +31,12 @@
  	movq %rsi, %rdi		/* shift arg1 - arg5.  */
  	movq %rdx, %rsi
  	movq %rcx, %rdx
--	movq %r8, %r10
-+	/* DEP 1/28/17: This is not the Linux kernel; use user-space calling
-+	 * 	convention	 */
-+	/*	movq %r8, %r10 */
-+	movq %r8, %rcx
++	/* DEP 8/17/17: Keep kernel calling
++	 * 	convention and fix in libOS */
+ 	movq %r8, %r10
  	movq %r9, %r8
  	movq 8(%rsp),%r9	/* arg6 is on the stack.  */
 -	syscall			/* Do the system call.  */
-+	SYSCALLDB		/* Do the system call.  */
++	SYSCALLDB			/* Do the system call.  */
  	cmpq $-4095, %rax	/* Check %rax for error.  */
  	jae SYSCALL_ERROR_LABEL	/* Jump to error handler if error.  */
  	ret			/* Return to caller.  */
diff --git a/Pal/src/db_events.c b/Pal/src/db_events.c
index c0ab4ac8..030a4590 100644
--- a/Pal/src/db_events.c
+++ b/Pal/src/db_events.c
@@ -128,10 +128,10 @@ static int event_close (PAL_HANDLE handle)
     return _DkEventClear(handle);
 }
 
-static int event_wait (PAL_HANDLE handle, int timeout)
+static int event_wait (PAL_HANDLE handle, uint64_t timeout)
 {
-    return timeout >=0 ? _DkEventWaitTimeout(handle, timeout) :
-           _DkEventWait(handle);
+    return timeout == NO_TIMEOUT ?    _DkEventWait(handle) : 
+        _DkEventWaitTimeout(handle, timeout);
 }
 
 struct handle_ops event_ops = {
diff --git a/Pal/src/db_semaphore.c b/Pal/src/db_semaphore.c
index ca9c0970..53911a0a 100644
--- a/Pal/src/db_semaphore.c
+++ b/Pal/src/db_semaphore.c
@@ -75,7 +75,7 @@ void DkSemaphoreRelease (PAL_HANDLE handle, PAL_NUM count)
     LEAVE_PAL_CALL();
 }
 
-static int sem_wait (PAL_HANDLE handle, int timeout)
+static int sem_wait (PAL_HANDLE handle, uint64_t timeout)
 {
     return _DkSemaphoreAcquireTimeout(handle, 1, timeout);
 }
diff --git a/Pal/src/host/Linux/db_events.c b/Pal/src/host/Linux/db_events.c
index b8ca36c9..e61155d9 100644
--- a/Pal/src/host/Linux/db_events.c
+++ b/Pal/src/host/Linux/db_events.c
@@ -79,7 +79,7 @@ int _DkEventSet (PAL_HANDLE event, int wakeup)
     return IS_ERR(ret) ? PAL_ERROR_TRYAGAIN : ret;
 }
 
-int _DkEventWaitTimeout (PAL_HANDLE event, int timeout)
+int _DkEventWaitTimeout (PAL_HANDLE event, uint64_t timeout)
 {
     int ret = 0;
 
diff --git a/Pal/src/host/Linux/db_mutex.c b/Pal/src/host/Linux/db_mutex.c
index 113480f7..4ac1255c 100644
--- a/Pal/src/host/Linux/db_mutex.c
+++ b/Pal/src/host/Linux/db_mutex.c
@@ -56,7 +56,7 @@
 
 #define MUTEX_SPINLOCK_TIMES    100
 
-int _DkMutexLockTimeout (struct mutex_handle * m, int timeout)
+int _DkMutexLockTimeout (struct mutex_handle * m, uint64_t timeout)
 {
     int ret = 0;
 #ifdef DEBUG_MUTEX
diff --git a/Pal/src/host/Linux/db_object.c b/Pal/src/host/Linux/db_object.c
index 0a19c74e..c4498a75 100644
--- a/Pal/src/host/Linux/db_object.c
+++ b/Pal/src/host/Linux/db_object.c
@@ -46,7 +46,7 @@
  *
  *  Returns 0 on success, negative value on failure (e.g., -PAL_ERROR_TRYAGAIN)
  */
-static int _DkObjectWaitOne (PAL_HANDLE handle, int timeout)
+static int _DkObjectWaitOne (PAL_HANDLE handle, uint64_t timeout)
 {
     /* only for all these handle which has a file descriptor, or
        a eventfd. events and semaphores will skip this part */
@@ -126,7 +126,7 @@ static int _DkObjectWaitOne (PAL_HANDLE handle, int timeout)
 
 /* _DkObjectsWaitAny for internal use. The function wait for any of the handle
    in the handle array. timeout can be set for the wait. */
-int _DkObjectsWaitAny (int count, PAL_HANDLE * handleArray, int timeout,
+int _DkObjectsWaitAny (int count, PAL_HANDLE * handleArray, uint64_t timeout,
                        PAL_HANDLE * polled)
 {
     if (count <= 0)
diff --git a/Pal/src/host/Linux/db_semaphore.c b/Pal/src/host/Linux/db_semaphore.c
index b6b32edf..25a0005f 100644
--- a/Pal/src/host/Linux/db_semaphore.c
+++ b/Pal/src/host/Linux/db_semaphore.c
@@ -82,7 +82,7 @@ void _DkSemaphoreDestroy (PAL_HANDLE semaphoreHandle)
     free(semaphoreHandle);
 }
 
-int _DkMutexLockTimeout (struct mutex_handle * mut, int timeout);
+int _DkMutexLockTimeout (struct mutex_handle * mut, uint64_t timeout);
 
 int _DkSemaphoreAcquire (PAL_HANDLE sem, int count)
 {
@@ -151,10 +151,10 @@ int _DkSemaphoreAcquire (PAL_HANDLE sem, int count)
     return ret;
 }
 
-int _DkSemaphoreAcquireTimeout (PAL_HANDLE sem, int count, int timeout)
+int _DkSemaphoreAcquireTimeout (PAL_HANDLE sem, int count, uint64_t timeout)
 {
     /* Pass it up to the no-timeout version if no timeout requested */
-    if (timeout == -1)
+    if (timeout == NO_TIMEOUT)
         return _DkSemaphoreAcquire(sem, count);
 
     /* optimization: use it as a mutex */
diff --git a/Pal/src/host/Linux/pal_linux.h b/Pal/src/host/Linux/pal_linux.h
index 6527343a..848078fd 100644
--- a/Pal/src/host/Linux/pal_linux.h
+++ b/Pal/src/host/Linux/pal_linux.h
@@ -156,7 +156,7 @@ bool stataccess (struct stat * stats, int acc);
 
 /* Locking and unlocking of Mutexes */
 int _DkMutexLock (struct mutex_handle * mut);
-int _DkMutexLockTimeout (struct mutex_handle * mut, int timeout);
+int _DkMutexLockTimeout (struct mutex_handle * mut, uint64_t timeout);
 int _DkMutexUnlock (struct mutex_handle * mut);
 
 void init_child_process (PAL_HANDLE * parent, PAL_HANDLE * exec,
diff --git a/Pal/src/pal.h b/Pal/src/pal.h
index 3adf71af..fc1bd3b4 100644
--- a/Pal/src/pal.h
+++ b/Pal/src/pal.h
@@ -466,7 +466,9 @@ DkEventClear (PAL_HANDLE eventHandle);
 
 #define NO_TIMEOUT      ((PAL_NUM) -1)
 
-/* assuming timeout to be in microseconds */
+/* assuming timeout to be in microseconds 
+ * NO_TIMEOUT means no timeout, as the name implies.
+ */
 /* Returns: NULL if the call times out, the ready handle on success */
 PAL_HANDLE
 DkObjectsWaitAny (PAL_NUM count, PAL_HANDLE * handleArray, PAL_NUM timeout);
diff --git a/Pal/src/pal_internal.h b/Pal/src/pal_internal.h
index 7e083933..9578626c 100644
--- a/Pal/src/pal_internal.h
+++ b/Pal/src/pal_internal.h
@@ -104,11 +104,12 @@ struct handle_ops {
     int (*attrsetbyhdl) (PAL_HANDLE handle, PAL_STREAM_ATTR * attr);
 
     /* 'wait' is used for synchronous wait.
+     * Time is in microseconds, NO_TIMEOUT means no timeout.
      * Returns 0 on success, a negative value on failure.
      * Timeout: -PAL_ERROR_TRYAGAIN
      * Positive return values are undefined.
      */
-    int (*wait) (PAL_HANDLE handle, int time);
+    int (*wait) (PAL_HANDLE handle, uint64_t time);
 
     /* 'rename' is used to change name of a stream, or reset its share
        option */
@@ -327,7 +328,7 @@ int _DkProcessSandboxCreate (const char * manifest, int flags);
 int _DkSemaphoreCreate (PAL_HANDLE handle, int initialCount, int maxCount);
 void _DkSemaphoreDestroy (PAL_HANDLE semaphoreHandle);
 int _DkSemaphoreAcquire (PAL_HANDLE sem, int count);
-int _DkSemaphoreAcquireTimeout (PAL_HANDLE sem, int count, int timeout);
+int _DkSemaphoreAcquireTimeout (PAL_HANDLE sem, int count, uint64_t timeout);
 void _DkSemaphoreRelease (PAL_HANDLE sem, int count);
 int _DkSemaphoreGetCurrentCount (PAL_HANDLE sem);
 
@@ -336,7 +337,7 @@ int _DkEventCreate (PAL_HANDLE * event, bool initialState,
                     bool isnotification);
 void _DkEventDestroy (PAL_HANDLE handle);
 int _DkEventSet (PAL_HANDLE event, int wakeup);
-int _DkEventWaitTimeout (PAL_HANDLE event, int timeout);
+int _DkEventWaitTimeout (PAL_HANDLE event, uint64_t timeout);
 int _DkEventWait (PAL_HANDLE event);
 int _DkEventClear (PAL_HANDLE event);
 
@@ -348,7 +349,7 @@ int _DkVirtualMemoryProtect (void * addr, uint64_t size, int prot);
 /* DkObject calls */
 int _DkObjectReference (PAL_HANDLE objectHandle);
 int _DkObjectClose (PAL_HANDLE objectHandle);
-int _DkObjectsWaitAny (int count, PAL_HANDLE * handleArray, int timeout,
+int _DkObjectsWaitAny (int count, PAL_HANDLE * handleArray, uint64_t timeout,
                        PAL_HANDLE * polled);
 
 /* DkException calls & structures */