mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: Sasha Levin <sasha.levin@oracle.com>
Cc: paulus@samba.org, Ingo Molnar <mingo@kernel.org>,
	acme@ghostprotocols.net, LKML <linux-kernel@vger.kernel.org>,
	Dave Jones <davej@redhat.com>
Subject: Re: perf: NULL ptr deref in perf_event_context_sched_in
Date: Wed, 10 Sep 2014 12:02:57 +0200	[thread overview]
Message-ID: <20140910100257.GP16043@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <540F53C9.6040800@oracle.com>

[-- Attachment #1: Type: text/plain, Size: 662 bytes --]

On Tue, Sep 09, 2014 at 03:23:53PM -0400, Sasha Levin wrote:

> While fuzzing with trinity inside a KVM tools guest running the latest -next
> kernel, I've stumbled on the following spew:
> 
> [ 1181.492212] BUG: unable to handle kernel NULL pointer dereference at 0000000000000040
> [ 1181.500717] IP: perf_event_context_sched_in (kernel/events/core.c:333 kernel/events/core.c:2575)

Oh joy:

static inline struct perf_cpu_context *
__get_cpu_context(struct perf_event_context *ctx)
{
	return this_cpu_ptr(ctx->pmu->pmu_cpu_context);
}

For some reason our pmu::pmu_cpu_context per-cpu storage is gone. Now
how did that happen.... /me puzzled

[-- Attachment #2: Type: application/pgp-signature, Size: 836 bytes --]

      reply	other threads:[~2014-09-10 10:03 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-09-09 19:23 Sasha Levin
2014-09-10 10:02 ` Peter Zijlstra [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20140910100257.GP16043@twins.programming.kicks-ass.net \
    --to=peterz@infradead.org \
    --cc=acme@ghostprotocols.net \
    --cc=davej@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=paulus@samba.org \
    --cc=sasha.levin@oracle.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

Powered by JetHome