1 files changed, 48 insertions, 16 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index 79de9f99a48d..3c31e874afad 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1129,7 +1129,6 @@ static void posix_cpu_timers_init(struct task_struct *tsk)
  */
 static struct task_struct *copy_process(unsigned long clone_flags,
                                         unsigned long stack_start,
-                                        struct pt_regs *regs,
                                         unsigned long stack_size,
                                         int __user *child_tidptr,
                                         struct pid *pid,
@@ -1321,7 +1320,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
         retval = copy_io(clone_flags, p);
         if (retval)
                 goto bad_fork_cleanup_namespaces;
-        retval = copy_thread(clone_flags, stack_start, stack_size, p, regs);
+        retval = copy_thread(clone_flags, stack_start, stack_size, p);
         if (retval)
                 goto bad_fork_cleanup_io;
 
@@ -1510,12 +1509,6 @@ fork_out:
         return ERR_PTR(retval);
 }
 
-noinline struct pt_regs * __cpuinit __attribute__((weak)) idle_regs(struct pt_regs *regs)
-{
-        memset(regs, 0, sizeof(struct pt_regs));
-        return regs;
-}
-
 static inline void init_idle_pids(struct pid_link *links)
 {
         enum pid_type type;
@@ -1529,10 +1522,7 @@ static inline void init_idle_pids(struct pid_link *links)
 struct task_struct * __cpuinit fork_idle(int cpu)
 {
         struct task_struct *task;
-        struct pt_regs regs;
-
-        task = copy_process(CLONE_VM, 0, idle_regs(&regs), 0, NULL,
-                            &init_struct_pid, 0);
+        task = copy_process(CLONE_VM, 0, 0, NULL, &init_struct_pid, 0);
         if (!IS_ERR(task)) {
                 init_idle_pids(task->pids);
                 init_idle(task, cpu);
@@ -1549,7 +1539,6 @@ struct task_struct * __cpuinit fork_idle(int cpu)
  */
 long do_fork(unsigned long clone_flags,
               unsigned long stack_start,
-              struct pt_regs *regs,
               unsigned long stack_size,
               int __user *parent_tidptr,
               int __user *child_tidptr)
@@ -1579,7 +1568,7 @@ long do_fork(unsigned long clone_flags,
          * requested, no event is reported; otherwise, report if the event
          * for the type of forking is enabled.
          */
-        if (!(clone_flags & CLONE_UNTRACED) && likely(user_mode(regs))) {
+        if (!(clone_flags & CLONE_UNTRACED)) {
                 if (clone_flags & CLONE_VFORK)
                         trace = PTRACE_EVENT_VFORK;
                 else if ((clone_flags & CSIGNAL) != SIGCHLD)
@@ -1591,7 +1580,7 @@ long do_fork(unsigned long clone_flags,
                         trace = 0;
         }
 
-        p = copy_process(clone_flags, stack_start, regs, stack_size,
+        p = copy_process(clone_flags, stack_start, stack_size,
                          child_tidptr, NULL, trace);
         /*
          * Do this prior waking up the new thread - the thread pointer
@@ -1635,11 +1624,54 @@ long do_fork(unsigned long clone_flags,
  */
 pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
 {
-        return do_fork(flags|CLONE_VM|CLONE_UNTRACED, (unsigned long)fn, NULL,
+        return do_fork(flags|CLONE_VM|CLONE_UNTRACED, (unsigned long)fn,
                 (unsigned long)arg, NULL, NULL);
 }
 #endif
 
+#ifdef __ARCH_WANT_SYS_FORK
+SYSCALL_DEFINE0(fork)
+{
+#ifdef CONFIG_MMU
+        return do_fork(SIGCHLD, 0, 0, NULL, NULL);
+#else
+        /* can not support in nommu mode */
+        return(-EINVAL);
+#endif
+}
+#endif
+
+#ifdef __ARCH_WANT_SYS_VFORK
+SYSCALL_DEFINE0(vfork)
+{
+        return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0, 
+                        0, NULL, NULL);
+}
+#endif
+
+#ifdef __ARCH_WANT_SYS_CLONE
+#ifdef CONFIG_CLONE_BACKWARDS
+SYSCALL_DEFINE5(clone, unsigned long, clone_flags, unsigned long, newsp,
+                 int __user *, parent_tidptr,
+                 int, tls_val,
+                 int __user *, child_tidptr)
+#elif defined(CONFIG_CLONE_BACKWARDS2)
+SYSCALL_DEFINE5(clone, unsigned long, newsp, unsigned long, clone_flags,
+                 int __user *, parent_tidptr,
+                 int __user *, child_tidptr,
+                 int, tls_val)
+#else
+SYSCALL_DEFINE5(clone, unsigned long, clone_flags, unsigned long, newsp,
+                 int __user *, parent_tidptr,
+                 int __user *, child_tidptr,
+                 int, tls_val)
+#endif
+{
+        return do_fork(clone_flags, newsp, 0,
+                parent_tidptr, child_tidptr);
+}
+#endif
+
 #ifndef ARCH_MIN_MMSTRUCT_ALIGN
 #define ARCH_MIN_MMSTRUCT_ALIGN 0
 #endif