From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754058Ab3BDQ5z (ORCPT ); Mon, 4 Feb 2013 11:57:55 -0500 Received: from mx1.redhat.com ([209.132.183.28]:55751 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753593Ab3BDQ5x (ORCPT ); Mon, 4 Feb 2013 11:57:53 -0500 Message-ID: <1359997059.11144.446.camel@bling.home> Subject: Re: [PATCH v3 3/3] QEMU-AER: Qemu changes to support AER for VFIO-PCI devices From: Alex Williamson To: "Pandarathil, Vijaymohan R" Cc: Gleb Natapov , Bjorn Helgaas , Blue Swirl , "Ortiz, Lance E" , "kvm@vger.kernel.org" , "qemu-devel@nongnu.org" , "linux-pci@vger.kernel.org" , "linux-kernel@vger.kernel.org" Date: Mon, 04 Feb 2013 09:57:39 -0700 In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2013-02-03 at 14:10 +0000, Pandarathil, Vijaymohan R wrote: > - Create eventfd per vfio device assigned to a guest and register an > event handler > > - This fd is passed to the vfio_pci driver through the SET_IRQ ioctl > > - When the device encounters an error, the eventfd is signalled > and the qemu eventfd handler gets invoked. > > - In the handler decide what action to take. Current action taken > is to terminate the guest. > > Signed-off-by: Vijay Mohan Pandarathil > --- > hw/vfio_pci.c | 105 +++++++++++++++++++++++++++++++++++++++++++++ > linux-headers/linux/vfio.h | 1 + > 2 files changed, 106 insertions(+) > > diff --git a/hw/vfio_pci.c b/hw/vfio_pci.c > index c51ae67..4e2f768 100644 > --- a/hw/vfio_pci.c > +++ b/hw/vfio_pci.c > @@ -130,6 +130,8 @@ typedef struct VFIODevice { > QLIST_ENTRY(VFIODevice) next; > struct VFIOGroup *group; > bool reset_works; > + EventNotifier err_notifier; > + bool pci_aer; Re-order these for alignment please. ie: struct VFIOGroup *group; EventNotifier err_notifier; bool reset_works; bool pci_aer; > } VFIODevice; > > typedef struct VFIOGroup { > @@ -1922,6 +1924,106 @@ static void vfio_put_device(VFIODevice *vdev) > } > } > > +static void vfio_err_notifier_handler(void *opaque) > +{ > + VFIODevice *vdev = opaque; > + > + if (!event_notifier_test_and_clear(&vdev->err_notifier)) { > + return; > + } > + > + /* > + * TBD. Retrieve the error details and decide what action > + * needs to be taken. One of the actions could be to pass > + * the error to the guest and have the guest driver recover > + * from the error. This requires that PCIe capabilities be > + * exposed to the guest. At present, we just terminate the > + * guest to contain the error. > + */ > + > + error_report("%s (%04x:%02x:%02x.%x)" > + "Unrecoverable error detected... Terminating guest\n", > + __func__, vdev->host.domain, vdev->host.bus, > + vdev->host.slot, vdev->host.function); > + > + hw_error("(%04x:%02x:%02x.%x) Unrecoverable device error\n", > + vdev->host.domain, vdev->host.bus, > + vdev->host.slot, vdev->host.function); > + > + return; As Blue Swirl mentions, these returns at the end of void functions are unnecessary. > +} > + > +static void vfio_register_err_notifier(VFIODevice *vdev) > +{ > + int ret; > + int argsz; > + struct vfio_irq_set *irq_set; > + int32_t *pfd; > + > + if (event_notifier_init(&vdev->err_notifier, 0)) { > + error_report("vfio: Warning: Unable to init event notifier for error detection\n"); > + return; > + } > + > + argsz = sizeof(*irq_set) + sizeof(*pfd); > + > + irq_set = g_malloc0(argsz); > + irq_set->argsz = argsz; > + irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | > + VFIO_IRQ_SET_ACTION_TRIGGER; > + irq_set->index = VFIO_PCI_ERR_IRQ_INDEX; > + irq_set->start = 0; > + irq_set->count = 1; > + pfd = (int32_t *)&irq_set->data; > + > + *pfd = event_notifier_get_fd(&vdev->err_notifier); > + qemu_set_fd_handler(*pfd, vfio_err_notifier_handler, NULL, vdev); > + > + ret = ioctl(vdev->fd, VFIO_DEVICE_SET_IRQS, irq_set); > + if (ret) { > + DPRINTF("vfio: Error notification not supported for the device\n"); We should know this already though, right? Where's our call to VFIO_DEVICE_GET_IRQ_INFO for this index? I'd expect that should happen in vfio_get_device where it can set some flag true, then this function would exit immediately if that flag isn't set. Then by the time we're here, it's a legitimate error_report if we think this should work and doesn't. > + qemu_set_fd_handler(*pfd, NULL, NULL, vdev); > + event_notifier_cleanup(&vdev->err_notifier); > + g_free(irq_set); > + return; > + } > + g_free(irq_set); > + vdev->pci_aer = 1; bool, so set to true or false. > + return; > +} > +static void vfio_unregister_err_notifier(VFIODevice *vdev) > +{ > + int argsz; > + struct vfio_irq_set *irq_set; > + int32_t *pfd; > + int ret; > + > + if (!vdev->pci_aer) { > + return; > + } > + > + argsz = sizeof(*irq_set) + sizeof(*pfd); > + > + irq_set = g_malloc0(argsz); > + irq_set->argsz = argsz; > + irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | > + VFIO_IRQ_SET_ACTION_TRIGGER; > + irq_set->index = VFIO_PCI_ERR_IRQ_INDEX; > + irq_set->start = 0; > + irq_set->count = 1; > + pfd = (int32_t *)&irq_set->data; > + *pfd = -1; > + > + ret = ioctl(vdev->fd, VFIO_DEVICE_SET_IRQS, irq_set); > + if (ret) { > + DPRINTF("vfio: Failed to de-assign error fd: %d\n", ret); This is also a legitimate error_report. In general, if kernel vfio-pci does or doesn't support a non-critical feature, that's a DPRINTF. If it's told us the feature is there and something doesn't work while setting it up, that's an error_report. Thanks, Alex > + } > + g_free(irq_set); > + qemu_set_fd_handler(event_notifier_get_fd(&vdev->err_notifier), > + NULL, NULL, vdev); > + event_notifier_cleanup(&vdev->err_notifier); > + return; > +} > static int vfio_initfn(PCIDevice *pdev) > { > VFIODevice *pvdev, *vdev = DO_UPCAST(VFIODevice, pdev, pdev); > @@ -2032,6 +2134,8 @@ static int vfio_initfn(PCIDevice *pdev) > } > } > > + vfio_register_err_notifier(vdev); > + > return 0; > > out_teardown: > @@ -2049,6 +2153,7 @@ static void vfio_exitfn(PCIDevice *pdev) > VFIODevice *vdev = DO_UPCAST(VFIODevice, pdev, pdev); > VFIOGroup *group = vdev->group; > > + vfio_unregister_err_notifier(vdev); > pci_device_set_intx_routing_notifier(&vdev->pdev, NULL); > vfio_disable_interrupts(vdev); > if (vdev->intx.mmap_timer) { > diff --git a/linux-headers/linux/vfio.h b/linux-headers/linux/vfio.h > index f787b72..6b20849 100644 > --- a/linux-headers/linux/vfio.h > +++ b/linux-headers/linux/vfio.h > @@ -310,6 +310,7 @@ enum { > VFIO_PCI_INTX_IRQ_INDEX, > VFIO_PCI_MSI_IRQ_INDEX, > VFIO_PCI_MSIX_IRQ_INDEX, > + VFIO_PCI_ERR_IRQ_INDEX, > VFIO_PCI_NUM_IRQS > }; >