From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752777AbdCHPjT (ORCPT ); Wed, 8 Mar 2017 10:39:19 -0500 Received: from Galois.linutronix.de ([146.0.238.70]:47271 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751972AbdCHPjO (ORCPT ); Wed, 8 Mar 2017 10:39:14 -0500 Date: Wed, 8 Mar 2017 16:37:32 +0100 From: Sebastian Andrzej Siewior To: Peter Zijlstra Cc: tglx@linutronix.de, mingo@kernel.org, juri.lelli@arm.com, rostedt@goodmis.org, xlpang@redhat.com, linux-kernel@vger.kernel.org, mathieu.desnoyers@efficios.com, jdesfossez@efficios.com, bristot@redhat.com, dvhart@infradead.org Subject: Re: [PATCH] futex: move debug_rt_mutex_free_waiter() further down Message-ID: <20170308153731.z3vjtb24h75eyv4u@linutronix.de> References: <20170304092717.762954142@infradead.org> <20170304093559.546712677@infradead.org> <20170308152901.kumylhi7l3hescxd@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20170308152901.kumylhi7l3hescxd@linutronix.de> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2017-03-08 16:29:02 [+0100], To Peter Zijlstra wrote: > Without this, futex_requeue_pi_signal_restart will trigger > > |kernel BUG at locking/rtmutex_common.h:55! > |Call Trace: > | rt_mutex_cleanup_proxy_lock+0x54/0x90 > | futex_wait_requeue_pi.constprop.21+0x387/0x4d0 > | do_futex+0x289/0xbf0 > |RIP: remove_waiter+0x157/0x170 RSP: ffffc90000e0fbe0 > > with BUG 2222222222222222 != pointer once this patch is applied. My wording is wrong. This BUG_ON() statement described here in this patch (together with the test case mentioned) will trigger once "[PATCH -v5 12/14] futex,rt_mutex: Restructure rt_mutex_finish_proxy_lock()" is applied. Sebastian