From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751939AbZJWLLl (ORCPT ); Fri, 23 Oct 2009 07:11:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751883AbZJWLLl (ORCPT ); Fri, 23 Oct 2009 07:11:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41644 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751351AbZJWLLk (ORCPT ); Fri, 23 Oct 2009 07:11:40 -0400 Date: Fri, 23 Oct 2009 13:08:38 +0200 From: "Michael S. Tsirkin" To: Rusty Russell Cc: linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, mtosatti@redhat.com, xma@us.ibm.com Subject: Re: [PATCH] virtio-pci: fix per-vq MSI-X request logic Message-ID: <20091023110838.GA20248@redhat.com> References: <20091022130606.GA6923@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20091022130606.GA6923@redhat.com> User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 22, 2009 at 03:06:06PM +0200, Michael S. Tsirkin wrote: > Commit f68d24082e22ccee3077d11aeb6dc5354f0ca7f1 > in 2.6.32-rc1 broke requesting IRQs for per-VQ MSI-X vectors: > - vector number was used instead of the vector itself > - we try to request an IRQ for VQ which does not > have a callback handler > > This is a regression that causes warnings in kernel log, > potentially lower performance as we need to scan vq list, > and might cause system failure if the interrupt > requested is in fact needed by another system. > > This was not noticed earlier because in most cases > we were falling back on shared interrupt for all vqs. > > The warnings often look like this: > > virtio-pci 0000:00:03.0: irq 26 for MSI/MSI-X > virtio-pci 0000:00:03.0: irq 27 for MSI/MSI-X > virtio-pci 0000:00:03.0: irq 28 for MSI/MSI-X > IRQ handler type mismatch for IRQ 1 > current handler: i8042 > Pid: 2400, comm: modprobe Tainted: G W > 2.6.32-rc3-11952-gf3ed8d8-dirty #1 > Call Trace: > [] ? __setup_irq+0x299/0x304 > [] ? request_threaded_irq+0x144/0x1c1 > [] ? vring_interrupt+0x0/0x30 > [] ? vp_try_to_find_vqs+0x583/0x5c7 > [] ? skb_recv_done+0x0/0x34 [virtio_net] > [] ? vp_find_vqs+0x2d/0x83 > [] ? vp_get+0x3c/0x4e > [] ? virtnet_probe+0x2f1/0x428 [virtio_net] > [] ? skb_recv_done+0x0/0x34 [virtio_net] > [] ? skb_xmit_done+0x0/0x39 [virtio_net] > [] ? sysfs_do_create_link+0xcb/0x116 > [] ? vp_get_status+0x14/0x16 > [] ? virtio_dev_probe+0xa9/0xc8 > [] ? driver_probe_device+0x8d/0x128 > [] ? __driver_attach+0x4f/0x6f > [] ? __driver_attach+0x0/0x6f > [] ? bus_for_each_dev+0x43/0x74 > [] ? bus_add_driver+0xea/0x22d > [] ? driver_register+0xa7/0x111 > [] ? init+0x0/0xc [virtio_net] > [] ? do_one_initcall+0x50/0x148 > [] ? sys_init_module+0xc5/0x21a > [] ? system_call_fastpath+0x16/0x1b > virtio-pci 0000:00:03.0: irq 26 for MSI/MSI-X > virtio-pci 0000:00:03.0: irq 27 for MSI/MSI-X > > Reported-by: Marcelo Tosatti > Reported-by: Shirley Ma > Signed-off-by: Michael S. Tsirkin You can now add Tested-by: Shirley Ma Tested-by: Marcelo Tosatti