On Tue, Oct 12, 2021 at 02:52:21PM +0800, Jason Wang wrote: > We used to synchronize pending MSI-X irq handlers via > synchronize_irq(), this may not work for the untrusted device which > may keep sending interrupts after reset which may lead unexpected > results. Similarly, we should not enable MSI-X interrupt until the > device is ready.
You mean until the driver is ready. > So this patch fixes those two issues by: > > 1) switching to use disable_irq() to prevent the virtio interrupt > handlers to be called after the device is reset. > 2) using IRQF_NO_AUTOEN and enable the MSI-X irq during .ready() > > This can make sure the virtio interrupt handler won't be called before > virtio_device_ready() and after reset. > > Cc: Thomas Gleixner <[email protected]> > Cc: Peter Zijlstra <[email protected]> > Cc: Paul E. McKenney <[email protected]> > Signed-off-by: Jason Wang <[email protected]> > --- > drivers/virtio/virtio_pci_common.c | 27 +++++++++++++++++++++------ > drivers/virtio/virtio_pci_common.h | 6 ++++-- > drivers/virtio/virtio_pci_legacy.c | 5 +++-- > drivers/virtio/virtio_pci_modern.c | 6 ++++-- > 4 files changed, 32 insertions(+), 12 deletions(-) > > diff --git a/drivers/virtio/virtio_pci_common.c > b/drivers/virtio/virtio_pci_common.c > index b35bb2d57f62..0b9523e6dd39 100644 > --- a/drivers/virtio/virtio_pci_common.c > +++ b/drivers/virtio/virtio_pci_common.c > @@ -24,8 +24,8 @@ MODULE_PARM_DESC(force_legacy, > "Force legacy mode for transitional virtio 1 devices"); > #endif > > -/* wait for pending irq handlers */ > -void vp_synchronize_vectors(struct virtio_device *vdev) > +/* disable irq handlers */ > +void vp_disable_vectors(struct virtio_device *vdev) > { > struct virtio_pci_device *vp_dev = to_vp_device(vdev); > int i; > @@ -34,7 +34,20 @@ void vp_synchronize_vectors(struct virtio_device *vdev) > synchronize_irq(vp_dev->pci_dev->irq); > > for (i = 0; i < vp_dev->msix_vectors; ++i) > - synchronize_irq(pci_irq_vector(vp_dev->pci_dev, i)); > + disable_irq(pci_irq_vector(vp_dev->pci_dev, i)); > +} > + > +/* enable irq handlers */ > +void vp_enable_vectors(struct virtio_device *vdev) > +{ > + struct virtio_pci_device *vp_dev = to_vp_device(vdev); > + int i; > + > + if (vp_dev->intx_enabled) > + return; > + > + for (i = 0; i < vp_dev->msix_vectors; ++i) > + enable_irq(pci_irq_vector(vp_dev->pci_dev, i)); > } > > /* the notify function used when creating a virt queue */ > @@ -141,7 +154,8 @@ static int vp_request_msix_vectors(struct virtio_device > *vdev, int nvectors, > snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names, > "%s-config", name); > err = request_irq(pci_irq_vector(vp_dev->pci_dev, v), > - vp_config_changed, 0, vp_dev->msix_names[v], > + vp_config_changed, IRQF_NO_AUTOEN, > + vp_dev->msix_names[v], > vp_dev); > if (err) > goto error; > @@ -160,7 +174,8 @@ static int vp_request_msix_vectors(struct virtio_device > *vdev, int nvectors, > snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names, > "%s-virtqueues", name); > err = request_irq(pci_irq_vector(vp_dev->pci_dev, v), > - vp_vring_interrupt, 0, vp_dev->msix_names[v], > + vp_vring_interrupt, IRQF_NO_AUTOEN, > + vp_dev->msix_names[v], > vp_dev); > if (err) > goto error; > @@ -337,7 +352,7 @@ static int vp_find_vqs_msix(struct virtio_device *vdev, > unsigned nvqs, > "%s-%s", > dev_name(&vp_dev->vdev.dev), names[i]); > err = request_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec), > - vring_interrupt, 0, > + vring_interrupt, IRQF_NO_AUTOEN, > vp_dev->msix_names[msix_vec], > vqs[i]); > if (err) > diff --git a/drivers/virtio/virtio_pci_common.h > b/drivers/virtio/virtio_pci_common.h > index beec047a8f8d..a235ce9ff6a5 100644 > --- a/drivers/virtio/virtio_pci_common.h > +++ b/drivers/virtio/virtio_pci_common.h > @@ -102,8 +102,10 @@ static struct virtio_pci_device *to_vp_device(struct > virtio_device *vdev) > return container_of(vdev, struct virtio_pci_device, vdev); > } > > -/* wait for pending irq handlers */ > -void vp_synchronize_vectors(struct virtio_device *vdev); > +/* disable irq handlers */ > +void vp_disable_vectors(struct virtio_device *vdev); > +/* enable irq handlers */ > +void vp_enable_vectors(struct virtio_device *vdev); > /* the notify function used when creating a virt queue */ > bool vp_notify(struct virtqueue *vq); > /* the config->del_vqs() implementation */ > diff --git a/drivers/virtio/virtio_pci_legacy.c > b/drivers/virtio/virtio_pci_legacy.c > index d62e9835aeec..bdf6bc667ab5 100644 > --- a/drivers/virtio/virtio_pci_legacy.c > +++ b/drivers/virtio/virtio_pci_legacy.c > @@ -97,8 +97,8 @@ static void vp_reset(struct virtio_device *vdev) > /* Flush out the status write, and flush in device writes, > * including MSi-X interrupts, if any. */ > ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS); > - /* Flush pending VQ/configuration callbacks. */ > - vp_synchronize_vectors(vdev); > + /* Disable VQ/configuration callbacks. */ > + vp_disable_vectors(vdev); > } > > static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) > @@ -194,6 +194,7 @@ static void del_vq(struct virtio_pci_vq_info *info) > } > > static const struct virtio_config_ops virtio_pci_config_ops = { > + .ready = vp_enable_vectors, > .get = vp_get, > .set = vp_set, > .get_status = vp_get_status, > diff --git a/drivers/virtio/virtio_pci_modern.c > b/drivers/virtio/virtio_pci_modern.c > index 30654d3a0b41..acf0f6b6381d 100644 > --- a/drivers/virtio/virtio_pci_modern.c > +++ b/drivers/virtio/virtio_pci_modern.c > @@ -172,8 +172,8 @@ static void vp_reset(struct virtio_device *vdev) > */ > while (vp_modern_get_status(mdev)) > msleep(1); > - /* Flush pending VQ/configuration callbacks. */ > - vp_synchronize_vectors(vdev); > + /* Disable VQ/configuration callbacks. */ > + vp_disable_vectors(vdev); > } > > static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) > @@ -380,6 +380,7 @@ static bool vp_get_shm_region(struct virtio_device *vdev, > } > > static const struct virtio_config_ops virtio_pci_config_nodev_ops = { > + .ready = vp_enable_vectors, > .get = NULL, > .set = NULL, > .generation = vp_generation, > @@ -397,6 +398,7 @@ static const struct virtio_config_ops > virtio_pci_config_nodev_ops = { > }; > > static const struct virtio_config_ops virtio_pci_config_ops = { > + .ready = vp_enable_vectors, > .get = vp_get, > .set = vp_set, > .generation = vp_generation, > -- > 2.25.1 _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
