Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Wed, 18 Apr 2018 14:59:15 +0100 (BST)
From:   James Simmons <jsimmons@infradead.org>
To:     Fengguang Wu <fengguang.wu@intel.com>
cc:     Oleg Drokin <oleg.drokin@intel.com>,
        Andreas Dilger <andreas.dilger@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Denis Petrovic <denis.petrovic@edu.ece.fr>,
        lustre-devel@lists.lustre.org, devel@driverdev.osuosl.org,
        linux-kernel@vger.kernel.org, lkp@01.org
Subject: Re: [cfs_trace_lock_tcd] BUG: unable to handle kernel NULL pointer
 dereference at 00000050
In-Reply-To: <20180418133831.uef7d77ejdyjtxgh@wfg-t540p.sh.intel.com>
Message-ID: <alpine.LFD.2.21.1804181456590.5599@casper.infradead.org>
References: <20180418133831.uef7d77ejdyjtxgh@wfg-t540p.sh.intel.com>
User-Agent: Alpine 2.21 (LFD 202 2017-01-01)
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk


> Hello,
> 
> FYI this happens in mainline kernel 4.17.0-rc1.
> It looks like a new regression.
> 
> [    7.587002]  lnet_selftest_init+0x2c4/0x5d9:
> 						lnet_selftest_init at drivers/staging/lustre/lnet/selftest/module.c:134
> [    7.587002]  ? lnet_selftest_exit+0x8d/0x8d:
> 						lnet_selftest_init at drivers/staging/lustre/lnet/selftest/module.c:90

Are you running lnet selftest ? Is this a UMP setup? The reason I ask is
that their is a SMP handling bug in lnet selftest. If you look at the
mailing list I pushed a SMP patch series. Can you try that series and
tell me if it works for you. Thanks