Re: PATCH? tracehook_report_clone: fix false positives

From: Roland McGrath
Date: Mon Jun 01 2009 - 19:20:15 EST


> I suspect you misread my previous question.

Apparently so.

> I didn't mean PTRACE_ATTACH should use ptrace_init_task). I just meant that
> perhaps it makes sense to move sigaddset() from tracehook_finish_clone()
> to tracehook_finish_clone()->ptrace_init_task().

You mean from tracehook_report_clone to ptrace_init_task. Perhaps.
tracehook_finish_clone->ptrace_init_task is inside write_lock_irq,
so it should really be kept to the minimum of what has to be inside there.

But the real reason is just that tracehook_report_clone() is called at the
place in do_fork() where the ptrace SIGSTOP code was originally before the
introduction of tracehook.h.

This is where the utrace attachment point has to be (i.e. outside all the
locking). So I don't see any benefit to changing the ptrace status quo now
for its own sake.


Thanks,
Roland
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