ptrace: introduce user_single_step_siginfo() helper
Suggested by Roland.
Currently there is no way to synthesize a single-stepping trap in the
arch-independent manner. This patch adds the default helper which fills
siginfo_t, arch/ can can override it.
Architetures which implement user_enable_single_step() should add
user_single_step_siginfo() also.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: <linux-arch@vger.kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h
index 1951805..56f2d63 100644
--- a/include/linux/ptrace.h
+++ b/include/linux/ptrace.h
@@ -273,6 +273,18 @@
}
#endif /* arch_has_block_step */
+#ifdef ARCH_HAS_USER_SINGLE_STEP_INFO
+extern void user_single_step_siginfo(struct task_struct *tsk,
+ struct pt_regs *regs, siginfo_t *info);
+#else
+static inline void user_single_step_siginfo(struct task_struct *tsk,
+ struct pt_regs *regs, siginfo_t *info)
+{
+ memset(info, 0, sizeof(*info));
+ info->si_signo = SIGTRAP;
+}
+#endif
+
#ifndef arch_ptrace_stop_needed
/**
* arch_ptrace_stop_needed - Decide whether arch_ptrace_stop() should be called