Date: Fri, 6 Nov 2009 22:50:04 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, linux-kernel@vger.kernel.org,
       linux-arch@vger.kernel.org
Subject: Re: [PATCH] ptrace: copy_thread() should clear TIF_SINGLESTEP and
	X86_EFLAGS_TF
Message-ID: <20091106215004.GA2232@redhat.com>
References: <20091106211637.GA1696@redhat.com> <20091106212554.BD731CF@magilla.sf.frob.com>
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On 11/06, Roland McGrath wrote:
>
> There is also the TIF_FORCED_TF logic to check.

I thought this flag has no effect without TIF_SINGLESTEP, and it is
always updated by enable_single_step().

> Probably it should just
> call user_disable_single_step() instead.  Perhaps copy_process() should
> just call that and then no per-arch changes would be required.

OK, thanks, will resend tomorrow.

user_disable_single_step() is very much arch-dependent, I am worried
if it is safe to call it from copy_process(), when the new task_struct,
thread_info, etc are not properly initialized yet...

Oleg.

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