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Date:   Wed, 7 Nov 2018 21:02:51 +0100
From:   Elvira Khabirova <lineprinter@altlinux.org>
To:     Oleg Nesterov <oleg@redhat.com>
Cc:     Andy Lutomirski <luto@amacapital.net>, rostedt@goodmis.org,
        mingo@redhat.com, linux-kernel@vger.kernel.org, ldv@altlinux.org,
        esyr@redhat.com, luto@kernel.org, strace-devel@lists.strace.io
Subject: Re: [RFC PATCH] ptrace: add PTRACE_GET_SYSCALL_INFO request
Message-ID: <20181107210251.542cf8a1@akathisia>
In-Reply-To: <20181107164443.GA8726@redhat.com>
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        <20181107164443.GA8726@redhat.com>
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On Wed, 7 Nov 2018 17:44:44 +0100
Oleg Nesterov <oleg@redhat.com> wrote:

> To me PT_IN_SYSCALL_STOP makes no real sense, but I won't argue.
> 
> At least I'd ask to not abuse task->ptrace. ptrace_report_syscall() can clear
> ->ptrace_message on exit if we really want PTRACE_GET_SYSCALL_INFO to fail after  
> that.

I really would not like to rely on ->ptrace_message remaining empty;
this looks too fragile.