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Date: Fri, 9 Sep 2011 18:14:59 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Tejun Heo <tj@kernel.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>, linux-kernel@vger.kernel.org,
        Denys Vlasenko <vda.linux@googlemail.com>
Subject: Re: Why I want PTRACE_O_TRACESTOP option
Message-ID: <20110909161459.GB23271@redhat.com>
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On 09/09, Tejun Heo wrote:
>
> To me, the rationale presented here almost argues against
> PTRACE_O_TRACESTOP.  :(

Personally I dislike PTRACE_O_TRACESTOP too.

And once again, this needs more (nontrivial) changes than just
s/PT_SEIZED/PTRACE_O_TRACESTOP/, the patch was wrong.

And, just for example. While this is minor, I'd like to improve
the error codes from ptrace_check_attach(). Until we drop
PTRACE_SEIZE_DEVEL we can safely do this. I don't think it makes
sense to add the new PTRACE_O for this.

And finally, I simply do not understand how it can be useful.

Oleg.