From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?ISO-8859-1?Q?Roger_Pau_Monn=E9?= Subject: Re: [Xen-devel] [GIT PULL] (xen) stable/for-jens-3.14 : NFO: trying to register non-static key. the code is fine but needs lockdep annotation. Date: Tue, 11 Feb 2014 18:40:02 +0100 Message-ID: <52FA6072.40908@citrix.com> References: <20140210184412.GA18198@phenom.dumpdata.com> <20140210195402.GA3924@kernel.dk> <771950784.20140211165215@eikelenboom.it> <20140211155650.GA23026@phenom.dumpdata.com> <1542261541.20140211170750@eikelenboom.it> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1542261541.20140211170750@eikelenboom.it> Sender: linux-kernel-owner@vger.kernel.org To: Sander Eikelenboom , Konrad Rzeszutek Wilk Cc: david.vrabel@citrix.com, mrushton@amazon.com, msw@amazon.com, boris.ostrovsky@oracle.com, Jens Axboe , xen-devel@lists.xensource.com, linux-kernel@vger.kernel.org List-Id: xen-devel@lists.xenproject.org On 11/02/14 17:07, Sander Eikelenboom wrote: >=20 > Tuesday, February 11, 2014, 4:56:50 PM, you wrote: >=20 >> On Tue, Feb 11, 2014 at 04:52:15PM +0100, Sander Eikelenboom wrote: >>> Hi Konrad, >>> >>> Today decided to tryout another kernel RC and your pull request to = Jens on top of it .. and I encoutered this one: >=20 >> Thank you for testing! >=20 >> Could you provide the .config file please? >=20 > Attached >=20 >> Did you see this _before_ the pull request with Jens? I presume >> not, but just double checking? >=20 > Nope not too my knowledge (though it's a bit messy with things broken= on 3.14 at the moment) >=20 >> And lastly - what were you doing when you triggered this? Just launc= hing >> a guest? >=20 > Nope it triggers on guest shutdown .. >=20 >=20 >> CC-ing Roger and other folks who were on the patches. >=20 >>> >>> >>> [ 438.029756] INFO: trying to register non-static key. >>> [ 438.029759] the code is fine but needs lockdep annotation. >>> [ 438.029760] turning off the locking correctness validator. >>> [ 438.029770] CPU: 3 PID: 9593 Comm: blkback.2.xvda Tainted: G = W 3.14.0-rc2-20140211-pcireset-net-btrevert-xenblock+ #1 >>> [ 438.029773] Hardware name: MSI MS-7640/890FXA-GD70 (MS-7640) , = BIOS V1.8B1 09/13/2010 >>> [ 438.029784] ffff88005224c4f0 ffff88004e5d9b68 ffffffff81b808c4 = ffff88004ba2b510 >>> [ 438.029791] 0000000000000002 ffff88004e5d9c38 ffffffff81116eab = ffff88004e5d9bf8 >>> [ 438.029798] ffffffff81117b35 0000000000000000 0000000000000000 = ffffffff82cee570 >>> [ 438.029799] Call Trace: >>> [ 438.029815] [] dump_stack+0x46/0x58 >>> [ 438.029826] [] __lock_acquire+0x1c2b/0x2220 >>> [ 438.029833] [] ? lock_acquire+0xe5/0x150 >>> [ 438.029841] [] lock_acquire+0xbd/0x150 >>> [ 438.029847] [] ? flush_work+0x5/0x290 >>> [ 438.029852] [] flush_work+0x3d/0x290 >>> [ 438.029856] [] ? flush_work+0x5/0x290 >>> [ 438.029863] [] ? lock_acquire+0xe5/0x150 >>> [ 438.029872] [] ? xen_blkif_schedule+0x1a1/0x8= d0 >>> [ 438.029881] [] ? _raw_spin_unlock_irqrestore+= 0x6d/0x90 >>> [ 438.029888] [] ? trace_hardirqs_on_caller+0xf= b/0x240 >>> [ 438.029894] [] ? trace_hardirqs_on+0xd/0x10 >>> [ 438.029901] [] xen_blkif_schedule+0x289/0x8d0 >>> [ 438.029907] [] ? __init_waitqueue_head+0x60/0= x60 >>> [ 438.029913] [] ? trace_hardirqs_on+0xd/0x10 >>> [ 438.029919] [] ? _raw_spin_unlock_irqrestore+= 0x81/0x90 >>> [ 438.029925] [] ? xen_blkif_be_int+0x40/0x40 >>> [ 438.029932] [] kthread+0xe4/0x100 >>> [ 438.029938] [] ? _raw_spin_unlock_irq+0x30/0x= 50 >>> [ 438.029946] [] ? __init_kthread_worker+0x70/0= x70 >>> [ 438.029951] [] ret_from_fork+0x7c/0xb0 >>> [ 438.029958] [] ? __init_kthread_worker+0x70/0= x70 >>> >>> Doesn't seem to serious .. but never the less :-) Thanks for the report! Does the following patch solve the problem? --- commit c1460953d081c8a18ac9e84fe90f696cdceae105 Author: Roger Pau Monne Date: Tue Feb 11 17:21:19 2014 +0100 xen-blkback: init persistent_purge_work work_struct =20 Do a dummy initialization of the persistent_purge_work work_struct on xen_blkif_alloc, so that when flush_work is called o= n shutdown the struct is initialized even if it hasn't been used. =20 Signed-off-by: Roger Pau Monn=E9 diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blk= back/xenbus.c index 84973c6..3df7575 100644 --- a/drivers/block/xen-blkback/xenbus.c +++ b/drivers/block/xen-blkback/xenbus.c @@ -129,6 +129,17 @@ static struct xen_blkif *xen_blkif_alloc(domid_t d= omid) blkif->free_pages_num =3D 0; atomic_set(&blkif->persistent_gnt_in_use, 0); atomic_set(&blkif->inflight, 0); + /* + * Init the work struct with a NULL function, this is done + * so that flush_work doesn't complain when shutting down if + * persistent_purge_work has not been used during the lifetime + * of this blkback instance. + * + * NB: In purge_persistent_gnt we make sure that + * persistent_purge_work is always correctly setup with a valid + * function pointer before being scheduled. + */ + INIT_WORK(&blkif->persistent_purge_work, NULL); =20 INIT_LIST_HEAD(&blkif->pending_free); =20