diff --git a/kernel/src/memory.rs b/kernel/src/memory.rs
index f98f1ad..54c2cff 100644
--- a/kernel/src/memory.rs
+++ b/kernel/src/memory.rs
@@ -106,7 +106,7 @@ impl Drop for KernelStack {
 /// Handle page fault at `addr`.
 /// Return true to continue, false to halt.
 pub fn handle_page_fault(addr: usize) -> bool {
-    debug!("page fault @ {:#x}", addr);
+    // debug!("page fault @ {:#x}", addr);
 
     // This is safe as long as page fault never happens in page fault handler
     unsafe { process_unsafe().vm.handle_page_fault(addr) }
diff --git a/kernel/src/syscall/mod.rs b/kernel/src/syscall/mod.rs
index 7bd1a77..a24f34a 100644
--- a/kernel/src/syscall/mod.rs
+++ b/kernel/src/syscall/mod.rs
@@ -59,8 +59,8 @@ pub fn syscall(id: usize, args: [usize; 6], tf: &mut TrapFrame) -> isize {
         SYS_MPROTECT => sys_mprotect(args[0], args[1], args[2]),
         SYS_MUNMAP => sys_munmap(args[0], args[1]),
         SYS_BRK => {
-            warn!("sys_brk is unimplemented");
-            Ok(0)
+            warn!("sys_brk is unimplemented, return -1");
+            Err(SysError::ENOMEM)
         }
         SYS_RT_SIGACTION => {
             warn!("sys_sigaction is unimplemented");
@@ -174,6 +174,7 @@ pub fn syscall(id: usize, args: [usize; 6], tf: &mut TrapFrame) -> isize {
         //        SYS_GETRLIMIT => sys_getrlimit(),
         SYS_GETRUSAGE => sys_getrusage(args[0], args[1] as *mut RUsage),
         SYS_SYSINFO => sys_sysinfo(args[0] as *mut SysInfo),
+        SYS_TIMES => sys_times(args[0] as *mut Tms),
         SYS_GETUID => {
             warn!("sys_getuid is unimplemented");
             Ok(0)
diff --git a/kernel/src/syscall/time.rs b/kernel/src/syscall/time.rs
index dd5cfcd..ff25cb3 100644
--- a/kernel/src/syscall/time.rs
+++ b/kernel/src/syscall/time.rs
@@ -146,3 +146,33 @@ pub fn sys_getrusage(who: usize, rusage: *mut RUsage) -> SysResult {
     unsafe { *rusage = new_rusage };
     Ok(0)
 }
+
+
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub struct Tms {
+    tms_utime: u64, /* user time */
+    tms_stime: u64,  /* system time */
+    tms_cutime: u64, /* user time of children */
+    tms_cstime: u64, /* system time of children */
+}
+
+
+pub fn sys_times(buf:*mut Tms)-> SysResult {
+    info!("times: buf: {:?}", buf);
+    let proc = process();
+    proc.vm.check_write_ptr(buf)?;
+
+    let tick_base = *TICK_BASE;
+    let tick = unsafe { crate::trap::TICK as u64 };
+
+    let new_buf = Tms {
+        tms_utime: 0,
+        tms_stime: 0,
+        tms_cutime: 0,
+        tms_cstime: 0,
+    };
+
+    unsafe { *buf = new_buf };
+    Ok(tick as usize)
+}
\ No newline at end of file