2 files changed, 31 insertions, 20 deletions

diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index 10911c93fbf1..49d9f9305247 100644
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -442,10 +442,9 @@ ENDPROC(vector_swi)
          * context switches, and waiting for our parent to respond.
          */
 __sys_trace:
-        mov     r2, scno
-        add     r1, sp, #S_OFF
-        mov     r0, #0                          @ trace entry [IP = 0]
-        bl      syscall_trace
+        mov     r1, scno
+        add     r0, sp, #S_OFF
+        bl      syscall_trace_enter
 
         adr     lr, BSYM(__sys_trace_return)    @ return address
         mov     scno, r0                        @ syscall number (possibly new)
@@ -457,10 +456,9 @@ __sys_trace:
 
 __sys_trace_return:
         str     r0, [sp, #S_R0 + S_OFF]!        @ save returned r0
-        mov     r2, scno
-        mov     r1, sp
-        mov     r0, #1                          @ trace exit [IP = 1]
-        bl      syscall_trace
+        mov     r1, scno
+        mov     r0, sp
+        bl      syscall_trace_exit
         b       ret_slow_syscall
 
         .align  5
diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index 592a39d0ef31..dab711e6e1ca 100644
--- a/arch/arm/kernel/ptrace.c
+++ b/arch/arm/kernel/ptrace.c
@@ -907,12 +907,18 @@ long arch_ptrace(struct task_struct *child, long request,
         return ret;
 }
 
-asmlinkage int syscall_trace(int why, struct pt_regs *regs, int scno)
+enum ptrace_syscall_dir {
+        PTRACE_SYSCALL_ENTER = 0,
+        PTRACE_SYSCALL_EXIT,
+};
+
+static int ptrace_syscall_trace(struct pt_regs *regs, int scno,
+                                enum ptrace_syscall_dir dir)
 {
         unsigned long ip;
 
         if (!test_thread_flag(TIF_SYSCALL_TRACE))
-                goto out_no_trace;
+                return scno;
 
         current_thread_info()->syscall = scno;
 
@@ -921,21 +927,28 @@ asmlinkage int syscall_trace(int why, struct pt_regs *regs, int scno)
          * IP = 0 -> entry, =1 -> exit
          */
         ip = regs->ARM_ip;
-        regs->ARM_ip = why;
+        regs->ARM_ip = dir;
 
-        if (why)
+        if (dir == PTRACE_SYSCALL_EXIT)
                 tracehook_report_syscall_exit(regs, 0);
         else if (tracehook_report_syscall_entry(regs))
                 current_thread_info()->syscall = -1;
 
         regs->ARM_ip = ip;
-        scno = current_thread_info()->syscall;
+        return current_thread_info()->syscall;
+}
 
-out_no_trace:
-        if (why)
-                audit_syscall_exit(regs);
-        else
-                audit_syscall_entry(AUDIT_ARCH_ARM, scno, regs->ARM_r0,
-                                    regs->ARM_r1, regs->ARM_r2, regs->ARM_r3);
-        return scno;
+asmlinkage int syscall_trace_enter(struct pt_regs *regs, int scno)
+{
+        int ret = ptrace_syscall_trace(regs, scno, PTRACE_SYSCALL_ENTER);
+        audit_syscall_entry(AUDIT_ARCH_ARM, scno, regs->ARM_r0, regs->ARM_r1,
+                            regs->ARM_r2, regs->ARM_r3);
+        return ret;
+}
+
+asmlinkage int syscall_trace_exit(struct pt_regs *regs, int scno)
+{
+        int ret = ptrace_syscall_trace(regs, scno, PTRACE_SYSCALL_EXIT);
+        audit_syscall_exit(regs);
+        return ret;
 }