Upgrade to 4.4.50-rt62

[kvmfornfv.git] / kernel / arch / arm64 / kernel / debug-monitors.c

diff --git a/kernel/arch/arm64/kernel/debug-monitors.c b/kernel/arch/arm64/kernel/debug-monitors.c
index c1492ba..c8875b6 100644 (file)
--- a/kernel/arch/arm64/kernel/debug-monitors.c
+++ b/kernel/arch/arm64/kernel/debug-monitors.c
@@ -152,7 +152,6 @@ static int debug_monitors_init(void)
        /* Clear the OS lock. */
        on_each_cpu(clear_os_lock, NULL, 1);
        isb();
-       local_dbg_enable();
 
        /* Register hotplug handler. */
        __register_cpu_notifier(&os_lock_nb);
@@ -423,8 +422,10 @@ int kernel_active_single_step(void)
 /* ptrace API */
 void user_enable_single_step(struct task_struct *task)
 {
-       set_ti_thread_flag(task_thread_info(task), TIF_SINGLESTEP);
-       set_regs_spsr_ss(task_pt_regs(task));
+       struct thread_info *ti = task_thread_info(task);
+
+       if (!test_and_set_ti_thread_flag(ti, TIF_SINGLESTEP))
+               set_regs_spsr_ss(task_pt_regs(task));
 }
 
 void user_disable_single_step(struct task_struct *task)