diff options
Diffstat (limited to 'drivers/vfio/pci/vfio_pci_intrs.c')
| -rw-r--r-- | drivers/vfio/pci/vfio_pci_intrs.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/drivers/vfio/pci/vfio_pci_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c index 9dd49c9839ac..553212f037c3 100644 --- a/drivers/vfio/pci/vfio_pci_intrs.c +++ b/drivers/vfio/pci/vfio_pci_intrs.c @@ -16,6 +16,7 @@ #include <linux/device.h> #include <linux/interrupt.h> #include <linux/eventfd.h> +#include <linux/msi.h> #include <linux/pci.h> #include <linux/file.h> #include <linux/poll.h> @@ -548,6 +549,20 @@ static int vfio_msi_set_vector_signal(struct vfio_pci_device *vdev, return PTR_ERR(trigger); } + /* + * The MSIx vector table resides in device memory which may be cleared + * via backdoor resets. We don't allow direct access to the vector + * table so even if a userspace driver attempts to save/restore around + * such a reset it would be unsuccessful. To avoid this, restore the + * cached value of the message prior to enabling. + */ + if (msix) { + struct msi_msg msg; + + get_cached_msi_msg(irq, &msg); + write_msi_msg(irq, &msg); + } + ret = request_irq(irq, vfio_msihandler, 0, vdev->ctx[vector].name, trigger); if (ret) { |