Blackfin: fix single stepping over system calls

On Blackfin systems, the hardware single step exception triggers before
the system call exception, so we need to save this info to process it
later on.  Otherwise, single stepping in userspace misses a few insns
right after the system call.

This is based a bit on the SuperH code added in commit 4b505db9c4c72dbd.

Reported-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/blackfin/include/asm/thread_info.h b/arch/blackfin/include/asm/thread_info.h
index 0149c92ceeb0..e9a5614cdbb1 100644
--- a/arch/blackfin/include/asm/thread_info.h
+++ b/arch/blackfin/include/asm/thread_info.h
@@ -103,6 +103,7 @@ static inline struct thread_info *current_thread_info(void)
 #define TIF_FREEZE              6       /* is freezing for suspend */
 #define TIF_IRQ_SYNC            7       /* sync pipeline stage */
 #define TIF_NOTIFY_RESUME       8       /* callback before returning to user */
+#define TIF_SINGLESTEP          9
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
@@ -113,6 +114,7 @@ static inline struct thread_info *current_thread_info(void)
 #define _TIF_FREEZE             (1<<TIF_FREEZE)
 #define _TIF_IRQ_SYNC           (1<<TIF_IRQ_SYNC)
 #define _TIF_NOTIFY_RESUME      (1<<TIF_NOTIFY_RESUME)
+#define _TIF_SINGLESTEP         (1<<TIF_SINGLESTEP)
 
 #define _TIF_WORK_MASK          0x0000FFFE      /* work to do on interrupt/exception return */