[Blackfin] arch: disable single stepping when delivering a signal
When delivering a signal, disable single stepping but call
ptrace_notify if it was enabled before. The idea was taken
from the x86 port.
Signed-off-by: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
diff --git a/arch/blackfin/kernel/signal.c b/arch/blackfin/kernel/signal.c
index cb9d883..dbc3bbf 100644
--- a/arch/blackfin/kernel/signal.c
+++ b/arch/blackfin/kernel/signal.c
@@ -42,6 +42,9 @@
#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+/* Location of the trace bit in SYSCFG. */
+#define TRACE_BITS 0x0001
+
struct fdpic_func_descriptor {
unsigned long text;
unsigned long GOT;
@@ -225,6 +228,16 @@
regs->r1 = (unsigned long)(&frame->info);
regs->r2 = (unsigned long)(&frame->uc);
+ /*
+ * Clear the trace flag 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.
+ */
+ if (regs->syscfg & TRACE_BITS) {
+ regs->syscfg &= ~TRACE_BITS;
+ ptrace_notify(SIGTRAP);
+ }
+
return 0;
give_sigsegv: