From: Peter Zijlstra <peterz@infradead.org>
To: Vince Weaver <vincent.weaver@maine.edu>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@kernel.org>,
linux-kernel@vger.kernel.org,
Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [perf] more perf_fuzzer memory corruption
Date: Mon, 5 May 2014 19:14:28 +0200 [thread overview]
Message-ID: <20140505171428.GU26782@laptop.programming.kicks-ass.net> (raw)
In-Reply-To: <alpine.DEB.2.10.1405051309160.31072@vincent-weaver-1.umelst.maine.edu>
On Mon, May 05, 2014 at 01:10:55PM -0400, Vince Weaver wrote:
> On Mon, 5 May 2014, Vince Weaver wrote:
>
> > (Although often things like to crash the instant my tested-by e-mails
> > clear the lkml list.)
>
> This did turn up on the core2 machine. I had been seeing this problem
> earlier but was hoping it was part of the memory corruption issue:
>
> [ 4918.921921] BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
> [ 4918.925692] IP: [<ffffffff81539fa6>] mutex_lock+0x19/0x37
> [ 4918.925692] Call Trace:
> [ 4918.925692] [<ffffffff810d10b7>] perf_event_init_context+0x7c/0x1c8
> [ 4918.925692] [<ffffffff810d126c>] perf_event_init_task+0x69/0x6d
> [ 4918.925692] [<ffffffff8103e1ff>] copy_process+0x5cc/0x163b
> [ 4918.925692] [<ffffffff8103f536>] do_fork+0x74/0x1dc
> [ 4918.925692] [<ffffffff8103f6b4>] SyS_clone+0x16/0x18
> [ 4918.925692] [<ffffffff81542c89>] stub_clone+0x69/0x90
Cute.. does the below cure?
---
Subject: perf: Fix perf_event_init_context()
From: Peter Zijlstra <peterz@infradead.org>
Date: Mon May 5 19:12:20 CEST 2014
perf_pin_task_context() can return NULL but perf_event_init_context()
assumes it will not, correct this.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
---
kernel/events/core.c | 2 ++
1 file changed, 2 insertions(+)
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -7745,6 +7745,8 @@ int perf_event_init_context(struct task_
* swapped under us.
*/
parent_ctx = perf_pin_task_context(parent, ctxn);
+ if (!parent_ctx)
+ return 0;
/*
* No need to check if parent_ctx != NULL here; since we saw
next prev parent reply other threads:[~2014-05-05 17:14 UTC|newest]
Thread overview: 81+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-04-15 21:37 [perf] more perf_fuzzer memory corruption Vince Weaver
2014-04-15 21:49 ` Thomas Gleixner
2014-04-16 3:21 ` Vince Weaver
2014-04-16 4:18 ` Vince Weaver
2014-04-16 14:15 ` Peter Zijlstra
2014-04-16 17:30 ` Vince Weaver
2014-04-16 17:43 ` Vince Weaver
2014-04-16 17:47 ` Peter Zijlstra
2014-04-17 9:48 ` Ingo Molnar
2014-04-17 11:45 ` Peter Zijlstra
2014-04-17 14:22 ` Ingo Molnar
2014-04-17 14:42 ` Vince Weaver
2014-04-17 14:54 ` Peter Zijlstra
2014-04-17 15:35 ` Vince Weaver
2014-04-18 14:45 ` Vince Weaver
2014-04-18 14:51 ` Vince Weaver
2014-04-18 15:23 ` Peter Zijlstra
2014-04-18 16:59 ` Peter Zijlstra
2014-04-18 17:15 ` Peter Zijlstra
2014-04-23 20:58 ` Vince Weaver
2014-04-25 2:51 ` Vince Weaver
2014-04-28 14:21 ` Vince Weaver
2014-04-28 19:38 ` Vince Weaver
2014-04-29 9:46 ` Peter Zijlstra
2014-04-29 18:21 ` Vince Weaver
2014-04-29 19:01 ` Peter Zijlstra
2014-04-29 20:59 ` Vince Weaver
2014-04-30 18:44 ` Peter Zijlstra
2014-04-30 21:08 ` Vince Weaver
2014-04-30 22:51 ` Thomas Gleixner
2014-05-01 10:26 ` Peter Zijlstra
2014-05-01 11:50 ` Peter Zijlstra
2014-05-01 12:35 ` Thomas Gleixner
2014-05-01 13:12 ` Peter Zijlstra
2014-05-01 13:29 ` Thomas Gleixner
2014-05-01 13:22 ` Vince Weaver
2014-05-01 14:07 ` Vince Weaver
2014-05-01 14:27 ` Vince Weaver
2014-05-01 15:09 ` Peter Zijlstra
2014-05-01 15:50 ` Vince Weaver
2014-05-01 16:31 ` Thomas Gleixner
2014-05-01 17:18 ` Vince Weaver
2014-05-01 18:49 ` Vince Weaver
2014-05-01 21:32 ` Vince Weaver
2014-05-02 11:15 ` Peter Zijlstra
2014-05-02 15:42 ` Peter Zijlstra
2014-05-02 16:22 ` Vince Weaver
2014-05-02 16:22 ` Peter Zijlstra
2014-05-02 16:43 ` Vince Weaver
2014-05-02 17:27 ` Peter Zijlstra
2014-05-02 17:46 ` Vince Weaver
2014-05-02 19:12 ` Thomas Gleixner
2014-05-02 20:15 ` Vince Weaver
2014-05-02 20:45 ` Thomas Gleixner
2014-05-03 2:32 ` Vince Weaver
2014-05-03 3:02 ` Vince Weaver
2014-05-03 7:33 ` Peter Zijlstra
2014-05-05 9:31 ` Peter Zijlstra
2014-05-05 16:00 ` Vince Weaver
2014-05-05 17:10 ` Vince Weaver
2014-05-05 17:14 ` Peter Zijlstra [this message]
2014-05-05 18:47 ` Vince Weaver
2014-05-05 19:36 ` Peter Zijlstra
2014-05-05 19:51 ` Vince Weaver
2014-05-06 1:06 ` Vince Weaver
2014-05-06 16:57 ` Vince Weaver
2014-05-07 16:45 ` Peter Zijlstra
2014-05-08 10:40 ` [tip:perf/core] perf: Fix perf_event_init_context() tip-bot for Peter Zijlstra
2014-05-05 17:29 ` [perf] more perf_fuzzer memory corruption Ingo Molnar
2014-05-06 4:51 ` Vince Weaver
2014-05-06 17:06 ` Vince Weaver
2014-05-07 19:12 ` Ingo Molnar
2014-05-07 19:11 ` Ingo Molnar
2014-05-08 10:40 ` [tip:perf/core] perf: Fix race in removing an event tip-bot for Peter Zijlstra
2014-05-02 17:06 ` [perf] more perf_fuzzer memory corruption Vince Weaver
2014-05-02 17:04 ` Peter Zijlstra
2014-04-29 19:26 ` Steven Rostedt
2014-04-29 8:52 ` Peter Zijlstra
2014-04-29 18:11 ` Vince Weaver
2014-04-29 19:21 ` Steven Rostedt
2014-04-28 17:48 ` Thomas Gleixner
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