Commit 440e6ca7 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Linus Torvalds

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: default avatarChristoph 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: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent fd341abb
......@@ -128,6 +128,8 @@ struct pt_regs {
#ifdef __KERNEL__
#define arch_has_single_step() (1)
#define user_mode(regs) \
(((regs)->ARM_cpsr & 0xf) == 0)
......
......@@ -452,12 +452,23 @@ void ptrace_cancel_bpt(struct task_struct *child)
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 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
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;
......
......@@ -13,20 +13,6 @@ extern void ptrace_cancel_bpt(struct task_struct *);
extern void ptrace_set_bpt(struct task_struct *);
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
*/
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment