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Date: Sat, 9 May 2009 16:12:16 +0200
Message-ID: <c62985530905090712l59de17fbh2085119f2574255a@mail.gmail.com>
Subject: Re: [RFC] convert ftrace syscall tracer to TRACE_EVENT()
From: =?ISO-8859-1?Q?Fr=E9d=E9ric_Weisbecker?= <fweisbec@gmail.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>, Tom Zanussi <tzanussi@gmail.com>,
       linux-kernel@vger.kernel.org, laijs@cn.fujitsu.com, rostedt@goodmis.org,
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Le 9 mai 2009 16:07, Ingo Molnar <mingo@elte.hu> a écrit :
>
> * Frédéric Weisbecker <fweisbec@gmail.com> wrote:
>
>> > Note, this assumes that all syscall types can be described via
>> > __field() - i think that's correct. (we dont want to deref
>> > strings as they are untrusted, and there are no arrays in
>> > syscall parameters)
>>
>> Yeah, but we can also define a __string_from_user(), should be
>> trivial.
>
> We cannot really do that, because we cannot check the type in a
> macro. So we dont know when to inject __field() versus
> __string_from_user().


Aah...you're right :-/



>
>> > Can you see any complication?
>>
>> Just about the order of headers to include and headers
>> dependencies....
>
> That is testable and any problems will be found at the build stage,
> so it should be solvable.
>
>        Ingo
>