From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:41048 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752353AbbJRAet (ORCPT ); Sat, 17 Oct 2015 20:34:49 -0400 Subject: Patch "net/xen-netfront: only napi_synchronize() if running" has been added to the 4.1-stable tree To: 3chas3@gmail.com, davem@davemloft.net, gregkh@linuxfoundation.org, kamatam@amazon.com Cc: , From: Date: Sat, 17 Oct 2015 17:34:48 -0700 Message-ID: <1445128488228200@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled net/xen-netfront: only napi_synchronize() if running to the 4.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-xen-netfront-only-napi_synchronize-if-running.patch and it can be found in the queue-4.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 274b045509175db0405c784be85e8cce116e6f7d Mon Sep 17 00:00:00 2001 From: Chas Williams <3chas3@gmail.com> Date: Thu, 27 Aug 2015 12:28:46 -0400 Subject: net/xen-netfront: only napi_synchronize() if running From: Chas Williams <3chas3@gmail.com> commit 274b045509175db0405c784be85e8cce116e6f7d upstream. If an interface isn't running napi_synchronize() will hang forever. [ 392.248403] rmmod R running task 0 359 343 0x00000000 [ 392.257671] ffff88003760fc88 ffff880037193b40 ffff880037193160 ffff88003760fc88 [ 392.267644] ffff880037610000 ffff88003760fcd8 0000000100014c22 ffffffff81f75c40 [ 392.277524] 0000000000bc7010 ffff88003760fca8 ffffffff81796927 ffffffff81f75c40 [ 392.287323] Call Trace: [ 392.291599] [] schedule+0x37/0x90 [ 392.298553] [] schedule_timeout+0x14b/0x280 [ 392.306421] [] ? irq_free_descs+0x69/0x80 [ 392.314006] [] ? internal_add_timer+0xb0/0xb0 [ 392.322125] [] msleep+0x37/0x50 [ 392.329037] [] xennet_disconnect_backend.isra.24+0xda/0x390 [xen_netfront] [ 392.339658] [] xennet_remove+0x2c/0x80 [xen_netfront] [ 392.348516] [] xenbus_dev_remove+0x59/0xc0 [ 392.356257] [] __device_release_driver+0x87/0x120 [ 392.364645] [] driver_detach+0xb8/0xc0 [ 392.371989] [] bus_remove_driver+0x59/0xe0 [ 392.379883] [] driver_unregister+0x30/0x70 [ 392.387495] [] xenbus_unregister_driver+0x12/0x20 [ 392.395908] [] netif_exit+0x10/0x775 [xen_netfront] [ 392.404877] [] SyS_delete_module+0x1d8/0x230 [ 392.412804] [] system_call_fastpath+0x12/0x71 Signed-off-by: Chas Williams <3chas3@gmail.com> Signed-off-by: David S. Miller Cc: "Kamata, Munehisa" Signed-off-by: Greg Kroah-Hartman --- drivers/net/xen-netfront.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -1353,7 +1353,8 @@ static void xennet_disconnect_backend(st queue->tx_evtchn = queue->rx_evtchn = 0; queue->tx_irq = queue->rx_irq = 0; - napi_synchronize(&queue->napi); + if (netif_running(info->netdev)) + napi_synchronize(&queue->napi); xennet_release_tx_bufs(queue); xennet_release_rx_bufs(queue); Patches currently in stable-queue which might be from 3chas3@gmail.com are queue-4.1/net-xen-netfront-only-napi_synchronize-if-running.patch