diff --git a/arch/sh/kernel/entry-common.S b/arch/sh/kernel/entry-common.S
index ab4ebb856c2a3cc7ca9f2e75ceb94c32ebdc1c22..b46728027195b15747b7b43f18a7e35e0a687623 100644
--- a/arch/sh/kernel/entry-common.S
+++ b/arch/sh/kernel/entry-common.S
@@ -224,7 +224,7 @@ work_resched:
syscall_exit_work:
! r0: current_thread_info->flags
! r8: current_thread_info
- tst #_TIF_SYSCALL_TRACE, r0
+ tst #_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP, r0
bt/s work_pending
tst #_TIF_NEED_RESCHED, r0
#ifdef CONFIG_TRACE_IRQFLAGS
diff --git a/arch/sh/kernel/ptrace.c b/arch/sh/kernel/ptrace.c
index 04ca13a041c160127077dddab6cfd507368fb319..855f7246cfffb4a4d597a11bd5ffc654a32e348a 100644
--- a/arch/sh/kernel/ptrace.c
+++ b/arch/sh/kernel/ptrace.c
@@ -8,7 +8,6 @@
* SuperH version: Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka
*
*/
-
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
@@ -20,8 +19,7 @@
#include <linux/slab.h>
#include <linux/security.h>
#include <linux/signal.h>
-
-#include <asm/io.h>
+#include <linux/io.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/system.h>
@@ -59,6 +57,23 @@ static inline int put_stack_long(struct task_struct *task, int offset,
return 0;
}
+static void ptrace_disable_singlestep(struct task_struct *child)
+{
+ clear_tsk_thread_flag(child, TIF_SINGLESTEP);
+
+ /*
+ * Ensure the UBC is not programmed at the next context switch.
+ *
+ * Normally this is not needed but there are sequences such as
+ * singlestep, signal delivery, and continue that leave the
+ * ubc_pc non-zero leading to spurious SIGTRAPs.
+ */
+ if (child->thread.ubc_pc != 0) {
+ ubc_usercnt -= 1;
+ child->thread.ubc_pc = 0;
+ }
+}
+
/*
* Called by kernel/ptrace.c when detaching..
*
@@ -66,7 +81,7 @@ static inline int put_stack_long(struct task_struct *task, int offset,
*/
void ptrace_disable(struct task_struct *child)
{
- /* nothing to do.. */
+ ptrace_disable_singlestep(child);
}
long arch_ptrace(struct task_struct *child, long request, long addr, long data)
@@ -76,7 +91,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
switch (request) {
/* when I and D space are separate, these will need to be fixed. */
- case PTRACE_PEEKTEXT: /* read word at location addr. */
+ case PTRACE_PEEKTEXT: /* read word at location addr. */
case PTRACE_PEEKDATA: {
unsigned long tmp;
int copied;
@@ -94,7 +109,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
unsigned long tmp;
ret = -EIO;
- if ((addr & 3) || addr < 0 ||
+ if ((addr & 3) || addr < 0 ||
addr > sizeof(struct user) - 3)
break;
@@ -129,7 +144,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
ret = -EIO;
- if ((addr & 3) || addr < 0 ||
+ if ((addr & 3) || addr < 0 ||
addr > sizeof(struct user) - 3)
break;
@@ -156,6 +171,9 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
else
clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+
+ ptrace_disable_singlestep(child);
+
child->exit_code = data;
wake_up_process(child);
ret = 0;
@@ -163,14 +181,15 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
}
/*
- * make the child exit. Best I can do is send it a sigkill.
- * perhaps it should be put in the status that it wants to
+ * make the child exit. Best I can do is send it a sigkill.
+ * perhaps it should be put in the status that it wants to
* exit.
*/
case PTRACE_KILL: {
ret = 0;
if (child->exit_state == EXIT_ZOMBIE) /* already dead */
break;
+ ptrace_disable_singlestep(child);
child->exit_code = SIGKILL;
wake_up_process(child);
break;
@@ -196,6 +215,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
ubc_usercnt += 1;
child->thread.ubc_pc = pc;
+ set_tsk_thread_flag(child, TIF_SINGLESTEP);
child->exit_code = data;
/* give it a chance to run. */
wake_up_process(child);
@@ -248,14 +268,15 @@ asmlinkage void do_syscall_trace(void)
{
struct task_struct *tsk = current;
- if (!test_thread_flag(TIF_SYSCALL_TRACE))
+ if (!test_thread_flag(TIF_SYSCALL_TRACE) &&
+ !test_thread_flag(TIF_SINGLESTEP))
return;
if (!(tsk->ptrace & PT_PTRACED))
return;
/* the 0x80 provides a way for the tracing parent to distinguish
between a syscall stop and SIGTRAP delivery */
- ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
- ? 0x80 : 0));
+ ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) &&
+ !test_thread_flag(TIF_SINGLESTEP) ? 0x80 : 0));
/*
* this isn't the same as continuing with a signal, but it will do
diff --git a/include/asm-sh/thread_info.h b/include/asm-sh/thread_info.h
index 279e70a77c75350a8ce7fc24e5fe707e766d69d6..31d55e3782d519571cfa62343d21e67ac13353ac 100644
--- a/include/asm-sh/thread_info.h
+++ b/include/asm-sh/thread_info.h
@@ -111,6 +111,7 @@ static inline struct thread_info *current_thread_info(void)
#define TIF_SIGPENDING 2 /* signal pending */
#define TIF_NEED_RESCHED 3 /* rescheduling necessary */
#define TIF_RESTORE_SIGMASK 4 /* restore signal mask in do_signal() */
+#define TIF_SINGLESTEP 5 /* singlestepping active */
#define TIF_USEDFPU 16 /* FPU was used by this task this quantum (SMP) */
#define TIF_POLLING_NRFLAG 17 /* true if poll_idle() is polling TIF_NEED_RESCHED */
#define TIF_MEMDIE 18
@@ -121,6 +122,7 @@ static inline struct thread_info *current_thread_info(void)
#define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
+#define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP)
#define _TIF_USEDFPU (1<<TIF_USEDFPU)
#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
#define _TIF_FREEZE (1<<TIF_FREEZE)