On Wed, Dec 12, 2012 at 03:26:35PM +0100, Paolo Bonzini wrote: > virtio-pci devices do not perform a full reset when zero is written > to the status field. While PCI-specific status is initialized, the > reset does not propagate down the qdev bus hierarchy. Because of > this, a virtio reset does not cancel in-flight I/O for virtio-scsi > (where the cancellation is handled automatically by the SCSI > devices underneath virtio-scsi-pci). > > The patch calls qdev_reset_all, which calls virtio_pci_reset, > instead of basically inlining the contents of the latter. > > Reported-by: Bryan Venteicher <bry...@daemoninthecloset.org> > Cc: Michael S. Tsirkin <m...@redhat.com> > Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
This is a device specific register, IMO it should reset very specific things not what happens to be on the bus. For example qdev resets the PCI header: will or will not this reset it? It should not but no easy way to figure out. Can't the required code just go into the virtio-scsi reset callback? > --- > hw/virtio-pci.c | 25 ++++++++++--------------- > 1 file changed, 10 insertions(+), 15 deletions(-) > > diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c > index 71f4fb5..a1685f1 100644 > --- a/hw/virtio-pci.c > +++ b/hw/virtio-pci.c > @@ -268,12 +268,10 @@ static void virtio_ioport_write(void *opaque, uint32_t > addr, uint32_t val) > case VIRTIO_PCI_QUEUE_PFN: > pa = (hwaddr)val << VIRTIO_PCI_QUEUE_ADDR_SHIFT; > if (pa == 0) { > - virtio_pci_stop_ioeventfd(proxy); > - virtio_reset(proxy->vdev); > - msix_unuse_all_vectors(&proxy->pci_dev); > - } > - else > + qdev_reset_all(&proxy->pci_dev.qdev); > + } else { > virtio_queue_set_addr(vdev, vdev->queue_sel, pa); > + } > break; > case VIRTIO_PCI_QUEUE_SEL: > if (val < VIRTIO_PCI_QUEUE_MAX) > @@ -285,19 +283,16 @@ static void virtio_ioport_write(void *opaque, uint32_t > addr, uint32_t val) > } > break; > case VIRTIO_PCI_STATUS: > - if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) { > - virtio_pci_stop_ioeventfd(proxy); > - } > - > virtio_set_status(vdev, val & 0xFF); > > - if (val & VIRTIO_CONFIG_S_DRIVER_OK) { > - virtio_pci_start_ioeventfd(proxy); > - } > - > if (vdev->status == 0) { > - virtio_reset(proxy->vdev); > - msix_unuse_all_vectors(&proxy->pci_dev); > + qdev_reset_all(&proxy->pci_dev.qdev); > + } else { > + if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) { > + virtio_pci_stop_ioeventfd(proxy); > + } else { > + virtio_pci_start_ioeventfd(proxy); > + } > } > > /* Linux before 2.6.34 sets the device as OK without enabling > -- > 1.8.0.1 >