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Date: Tue, 1 Apr 2014 17:35:05 -0700
Message-ID: <CA+55aFyQHdtgQpnS7ar2db5QoZhmMStH_LgxHvAaCUbVEx_PQQ@mail.gmail.com>
Subject: Re: [GIT PULL] x86 LTO changes for v3.15
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: "H. Peter Anvin" <hpa@linux.intel.com>, Andi Kleen <ak@linux.intel.com>,
        Gleb Natapov <gleb@redhat.com>, Peter Anvin <hpa@zytor.com>,
        Jan Hubicka <hubicka@ucw.cz>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>, Paolo Bonzini <pbonzini@redhat.com>,
        Jaroslav Kysela <perex@perex.cz>,
        Peter Zijlstra <peterz@infradead.org>,
        Rusty Russell <rusty@rustcorp.com.au>,
        Thomas Gleixner <tglx@linutronix.de>
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On Tue, Apr 1, 2014 at 5:01 PM, Steven Rostedt <rostedt@goodmis.org> wrote:
>
> Why would they break tracing? I remember there was a issue with compat
> calls, are these related to that?

They "break" tracing by being invisible to syscall tracing. As you
really should know ;)

The syscall tracing feature depends on the wrappers that
SYSCALL_DEFINEx() creates. See the SYSCALL_TRACE_ENTER_EVENT() etc
crud in <linux/syscalls.h>

So there's no SYSCALL_METADATA for those system calls that weren't
created with the proper SYSCALL_DEFINE() wrappers.

                  Linus
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