From: Joerg Roedel <joro@8bytes.org>
To: Borislav Petkov <bp@alien8.de>, Ingo Molnar <mingo@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Arnaldo Carvalho de Melo <acme@infradead.org>,
lkml <linux-kernel@vger.kernel.org>,
Stephane Eranian <eranian@google.com>,
Namhyung Kim <namhyung.kim@lge.com>, Jiri Olsa <jolsa@redhat.com>,
Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: BUG: using smp_processor_id() in preemptible [00000000] code: asm/8267
Date: Wed, 27 Mar 2013 14:15:32 +0100 [thread overview]
Message-ID: <20130327131532.GL30540@8bytes.org> (raw)
In-Reply-To: <20130326183452.GC27518@pd.tnic>
On Tue, Mar 26, 2013 at 07:34:52PM +0100, Borislav Petkov wrote:
> diff --git a/kernel/events/core.c b/kernel/events/core.c
> index 7b4a55d41efc..f3bb3384a106 100644
> --- a/kernel/events/core.c
> +++ b/kernel/events/core.c
> @@ -4455,8 +4455,11 @@ static void perf_event_task_event(struct perf_task_event *task_event)
> next:
> put_cpu_ptr(pmu->pmu_cpu_context);
> }
> +
> + preempt_disable();
> if (task_event->task_ctx)
> perf_event_task_ctx(task_event->task_ctx, task_event);
> + preempt_enable();
>
> rcu_read_unlock();
> }
What makes me wonder here is that the code is preemptible in an
rcu_read_locked section. As far as I know preemption needs to be
disabled while holding the rcu_read_lock().
Joerg
next prev parent reply other threads:[~2013-03-27 13:15 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-03-24 11:55 BUG: using smp_processor_id() in preemptible [00000000] code: asm/8267 Borislav Petkov
2013-03-24 15:59 ` Borislav Petkov
2013-03-26 18:34 ` Borislav Petkov
2013-03-27 6:02 ` Namhyung Kim
2013-03-27 9:49 ` Borislav Petkov
2013-03-27 10:42 ` Jiri Olsa
2013-03-27 14:09 ` Peter Zijlstra
2013-03-27 16:31 ` Borislav Petkov
2013-04-30 15:27 ` [RFCv2] " Jiri Olsa
2013-03-27 13:15 ` Joerg Roedel [this message]
2013-03-27 14:17 ` Peter Zijlstra
2013-03-27 14:37 ` Paul E. McKenney
2013-03-27 16:34 ` Joerg Roedel
2013-03-27 16:38 ` Borislav Petkov
2013-03-27 18:04 ` Paul E. McKenney
2013-03-27 19:07 ` Borislav Petkov
2013-03-27 19:20 ` Borislav Petkov
2013-03-27 19:22 ` Paul E. McKenney
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