alpha: 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, 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>
Acked-by: Matt Turner <mattst88@gmail.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Christoph Hellwig 2010-03-10 15:22:47 -08:00 committed by Linus Torvalds
parent dacbe41f77
commit fd341abba6
2 changed files with 13 additions and 47 deletions

View File

@ -68,6 +68,7 @@ struct switch_stack {
#ifdef __KERNEL__
#define arch_has_single_step() (1)
#define user_mode(regs) (((regs)->ps & 8) != 0)
#define instruction_pointer(regs) ((regs)->pc)
#define profile_pc(regs) instruction_pointer(regs)

View File

@ -249,6 +249,17 @@ ptrace_cancel_bpt(struct task_struct * child)
return (nsaved != 0);
}
void user_enable_single_step(struct task_struct *child)
{
/* Mark single stepping. */
task_thread_info(child)->bpt_nsaved = -1;
}
void user_disable_single_step(struct task_struct *child)
{
ptrace_cancel_bpt(child);
}
/*
* Called by kernel/ptrace.c when detaching..
*
@ -256,7 +267,7 @@ ptrace_cancel_bpt(struct task_struct * child)
*/
void ptrace_disable(struct task_struct *child)
{
ptrace_cancel_bpt(child);
user_disable_single_step(child);
}
long arch_ptrace(struct task_struct *child, long request, long addr, long data)
@ -295,52 +306,6 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
DBG(DBG_MEM, ("poke $%ld<-%#lx\n", addr, data));
ret = put_reg(child, addr, data);
break;
case PTRACE_SYSCALL:
/* continue and stop at next (return from) syscall */
case PTRACE_CONT: /* restart after signal. */
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;
/* make sure single-step breakpoint is gone. */
ptrace_cancel_bpt(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:
ret = 0;
if (child->exit_state == EXIT_ZOMBIE)
break;
child->exit_code = SIGKILL;
/* make sure single-step breakpoint is gone. */
ptrace_cancel_bpt(child);
wake_up_process(child);
break;
case PTRACE_SINGLESTEP: /* execute single instruction. */
ret = -EIO;
if (!valid_signal(data))
break;
/* Mark single stepping. */
task_thread_info(child)->bpt_nsaved = -1;
clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
child->exit_code = data;
wake_up_process(child);
/* give it a chance to run. */
ret = 0;
break;
default:
ret = ptrace_request(child, request, addr, data);
break;