arm: use generic ptrace_resume code
Use the generic ptrace_resume code for PTRACE_SYSCALL, PTRACE_CONT,
PTRACE_KILL and PTRACE_SINGLESTEP. This implies defining
arch_has_single_step in <asm/ptrace.h> and implementing the
user_enable_single_step and user_disable_single_step functions, which also
causes the breakpoint information to be cleared on fork, which could be
considered a bug fix.
Also the TIF_SYSCALL_TRACE thread flag is now cleared on PTRACE_KILL which
it previously wasn't and the single stepping disable only happens if the
tracee process isn't a zombie yet, which is consistent with all
architectures using the modern ptrace code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/arm/include/asm/ptrace.h b/arch/arm/include/asm/ptrace.h
index eec6e89..9dcb11e 100644
--- a/arch/arm/include/asm/ptrace.h
+++ b/arch/arm/include/asm/ptrace.h
@@ -128,6 +128,8 @@
#ifdef __KERNEL__
+#define arch_has_single_step() (1)
+
#define user_mode(regs) \
(((regs)->ARM_cpsr & 0xf) == 0)
diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index 08f899f..3f562a7 100644
--- a/arch/arm/kernel/ptrace.c
+++ b/arch/arm/kernel/ptrace.c
@@ -452,12 +452,23 @@
clear_breakpoint(child, &child->thread.debug.bp[i]);
}
+void user_disable_single_step(struct task_struct *task)
+{
+ task->ptrace &= ~PT_SINGLESTEP;
+ ptrace_cancel_bpt(task);
+}
+
+void user_enable_single_step(struct task_struct *task)
+{
+ task->ptrace |= PT_SINGLESTEP;
+}
+
/*
* Called by kernel/ptrace.c when detaching..
*/
void ptrace_disable(struct task_struct *child)
{
- single_step_disable(child);
+ user_disable_single_step(child);
}
/*
@@ -753,53 +764,6 @@
ret = ptrace_write_user(child, addr, data);
break;
- /*
- * continue/restart and stop at next (return from) syscall
- */
- case PTRACE_SYSCALL:
- case PTRACE_CONT:
- ret = -EIO;
- if (!valid_signal(data))
- break;
- if (request == PTRACE_SYSCALL)
- set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
- else
- clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
- child->exit_code = data;
- single_step_disable(child);
- wake_up_process(child);
- ret = 0;
- break;
-
- /*
- * 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:
- single_step_disable(child);
- if (child->exit_state != EXIT_ZOMBIE) {
- child->exit_code = SIGKILL;
- wake_up_process(child);
- }
- ret = 0;
- break;
-
- /*
- * execute single instruction.
- */
- case PTRACE_SINGLESTEP:
- ret = -EIO;
- if (!valid_signal(data))
- break;
- single_step_enable(child);
- clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
- child->exit_code = data;
- /* give it a chance to run. */
- wake_up_process(child);
- ret = 0;
- break;
-
case PTRACE_GETREGS:
ret = ptrace_getregs(child, (void __user *)data);
break;
diff --git a/arch/arm/kernel/ptrace.h b/arch/arm/kernel/ptrace.h
index def3b61..3926605 100644
--- a/arch/arm/kernel/ptrace.h
+++ b/arch/arm/kernel/ptrace.h
@@ -14,20 +14,6 @@
extern void ptrace_break(struct task_struct *, struct pt_regs *);
/*
- * make sure single-step breakpoint is gone.
- */
-static inline void single_step_disable(struct task_struct *task)
-{
- task->ptrace &= ~PT_SINGLESTEP;
- ptrace_cancel_bpt(task);
-}
-
-static inline void single_step_enable(struct task_struct *task)
-{
- task->ptrace |= PT_SINGLESTEP;
-}
-
-/*
* Send SIGTRAP if we're single-stepping
*/
static inline void single_step_trap(struct task_struct *task)