On Sun, 2013-07-14 at 01:48 -0600, Vijay Mohan Pandarathil wrote: > Add support for error containment when a VFIO device assigned to a KVM > guest encounters an error. This is for PCIe devices/drivers that support AER > functionality. When the host OS is notified of an error in a device either > through the firmware first approach or through an interrupt handled by the AER > root port driver, the error handler registered by the vfio-pci driver gets > invoked. The qemu process is signaled through an eventfd registered per > VFIO device by the qemu process. In the eventfd handler, qemu decides on > what action to take. In this implementation, guest is brought down to > contain the error. > > The kernel patches for the above functionality has been already accepted. > > This is a refresh of the QEMU patch which was reviewed earlier. > http://marc.info/?l=linux-kernel&m=136281557608087&w=2 > This patch has the same contents and has been built after refreshing > to latest upstream and after the linux headers have been updated in qemu. > > - 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 stop the guest. > > Signed-off-by: Vijay Mohan Pandarathil <vijaymohan.pandarathil@xxxxxx> > --- > hw/misc/vfio.c | 123 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 123 insertions(+) Applied. Thanks, Alex > diff --git a/hw/misc/vfio.c b/hw/misc/vfio.c > index 540c377..414c999 100644 > --- a/hw/misc/vfio.c > +++ b/hw/misc/vfio.c > @@ -158,6 +158,7 @@ typedef struct VFIODevice { > PCIHostDeviceAddress host; > QLIST_ENTRY(VFIODevice) next; > struct VFIOGroup *group; > + EventNotifier err_notifier; > uint32_t features; > #define VFIO_FEATURE_ENABLE_VGA_BIT 0 > #define VFIO_FEATURE_ENABLE_VGA (1 << VFIO_FEATURE_ENABLE_VGA_BIT) > @@ -165,6 +166,7 @@ typedef struct VFIODevice { > uint8_t pm_cap; > bool reset_works; > bool has_vga; > + bool pci_aer; > } VFIODevice; > > typedef struct VFIOGroup { > @@ -2781,6 +2783,7 @@ static int vfio_get_device(VFIOGroup *group, const char *name, VFIODevice *vdev) > { > struct vfio_device_info dev_info = { .argsz = sizeof(dev_info) }; > struct vfio_region_info reg_info = { .argsz = sizeof(reg_info) }; > + struct vfio_irq_info irq_info = { .argsz = sizeof(irq_info) }; > int ret, i; > > ret = ioctl(group->fd, VFIO_GROUP_GET_DEVICE_FD, name); > @@ -2924,6 +2927,18 @@ static int vfio_get_device(VFIOGroup *group, const char *name, VFIODevice *vdev) > > vdev->has_vga = true; > } > + irq_info.index = VFIO_PCI_ERR_IRQ_INDEX; > + > + ret = ioctl(vdev->fd, VFIO_DEVICE_GET_IRQ_INFO, &irq_info); > + if (ret) { > + /* This can fail for an old kernel or legacy PCI dev */ > + DPRINTF("VFIO_DEVICE_GET_IRQ_INFO failure ret=%d\n", ret); > + ret = 0; > + } else if (irq_info.count == 1) { > + vdev->pci_aer = true; > + } else { > + error_report("vfio: Warning: Could not enable error recovery for the device\n"); > + } > > error: > if (ret) { > @@ -2946,6 +2961,112 @@ 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. For now, we just terminate the > + * guest to contain the error. > + */ > + > + error_report("%s (%04x:%02x:%02x.%x)" > + "Unrecoverable error detected...\n" > + "Please collect any data possible and then kill the guest", > + __func__, vdev->host.domain, vdev->host.bus, > + vdev->host.slot, vdev->host.function); > + > + vm_stop(RUN_STATE_IO_ERROR); > +} > + > +/* > + * Registers error notifier for devices supporting error recovery. > + * If we encounter a failure in this function, we report an error > + * and continue after disabling error recovery support for the > + * device. > + */ > +static void vfio_register_err_notifier(VFIODevice *vdev) > +{ > + int ret; > + int argsz; > + struct vfio_irq_set *irq_set; > + int32_t *pfd; > + > + if (!vdev->pci_aer) { > + return; > + } > + > + if (event_notifier_init(&vdev->err_notifier, 0)) { > + error_report("vfio: Warning: Unable to init event notifier for error detection\n"); > + vdev->pci_aer = false; > + 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) { > + error_report("vfio: Failed to set up error notification\n"); > + qemu_set_fd_handler(*pfd, NULL, NULL, vdev); > + event_notifier_cleanup(&vdev->err_notifier); > + vdev->pci_aer = false; > + } > + g_free(irq_set); > +} > + > +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) { > + error_report("vfio: Failed to de-assign error fd: %d\n", ret); > + } > + g_free(irq_set); > + qemu_set_fd_handler(event_notifier_get_fd(&vdev->err_notifier), > + NULL, NULL, vdev); > + event_notifier_cleanup(&vdev->err_notifier); > +} > + > static int vfio_initfn(PCIDevice *pdev) > { > VFIODevice *pvdev, *vdev = DO_UPCAST(VFIODevice, pdev, pdev); > @@ -3078,6 +3199,7 @@ static int vfio_initfn(PCIDevice *pdev) > } > > add_boot_device_path(vdev->bootindex, &pdev->qdev, NULL); > + vfio_register_err_notifier(vdev); > > return 0; > > @@ -3097,6 +3219,7 @@ 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) { -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
