diff options
Diffstat (limited to 'arch/x86/kernel/signal.c')
| -rw-r--r-- | arch/x86/kernel/signal.c | 22 |
1 files changed, 11 insertions, 11 deletions
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index f9804080ccb3..1ea14fd53933 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -616,7 +616,8 @@ setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs) static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) { - bool failed; + bool stepping, failed; + /* Are we from a system call? */ if (syscall_get_nr(current, regs) >= 0) { /* If so, check system call restarting.. */ @@ -640,12 +641,13 @@ handle_signal(struct ksignal *ksig, struct pt_regs *regs) } /* - * If TF is set due to a debugger (TIF_FORCED_TF), clear the TF - * flag so that register information in the sigcontext is correct. + * If TF is set due to a debugger (TIF_FORCED_TF), clear TF now + * so that register information in the sigcontext is correct and + * then notify the tracer before entering the signal handler. */ - if (unlikely(regs->flags & X86_EFLAGS_TF) && - likely(test_and_clear_thread_flag(TIF_FORCED_TF))) - regs->flags &= ~X86_EFLAGS_TF; + stepping = test_thread_flag(TIF_SINGLESTEP); + if (stepping) + user_disable_single_step(current); failed = (setup_rt_frame(ksig, regs) < 0); if (!failed) { @@ -656,10 +658,8 @@ handle_signal(struct ksignal *ksig, struct pt_regs *regs) * it might disable possible debug exception from the * signal handler. * - * Clear TF when entering the signal handler, but - * notify any tracer that was single-stepping it. - * The tracer may want to single-step inside the - * handler too. + * Clear TF for the case when it wasn't set by debugger to + * avoid the recursive send_sigtrap() in SIGTRAP handler. */ regs->flags &= ~(X86_EFLAGS_DF|X86_EFLAGS_RF|X86_EFLAGS_TF); /* @@ -668,7 +668,7 @@ handle_signal(struct ksignal *ksig, struct pt_regs *regs) if (used_math()) fpu_reset_state(current); } - signal_setup_done(failed, ksig, test_thread_flag(TIF_SINGLESTEP)); + signal_setup_done(failed, ksig, stepping); } #ifdef CONFIG_X86_32 |