On Mon, 2014-09-01 at 10:53 +1000, Gavin Shan wrote:
> The PCI device MSIx table is cleaned out in hardware after EEH PE
> reset. However, we still hold the stale MSIx entries in QEMU, which
> should be cleared accordingly. Otherwise, we will run into another
> (recursive) EEH error and the PCI devices contained in the PE have
> to be offlined exceptionally.
>
> The patch clears stale MSIx table before EEH PE reset so that MSIx
> table could be restored properly after EEH PE reset.
>
> Signed-off-by: Gavin Shan <gws...@linux.vnet.ibm.com>
> ---
> hw/misc/vfio.c | 32 +++++++++++++++++++++++++++++++-
> 1 file changed, 31 insertions(+), 1 deletion(-)
>
> diff --git a/hw/misc/vfio.c b/hw/misc/vfio.c
> index 1a3e7eb..1f55051 100644
> --- a/hw/misc/vfio.c
> +++ b/hw/misc/vfio.c
> @@ -2724,6 +2724,17 @@ static void vfio_disable_interrupts(VFIODevice *vdev)
> }
> }
>
> +static void vfio_disable_and_reset_interrupts(VFIODevice *vdev)
> +{
> + vfio_disable_interrupts(vdev);
> +
> + switch (vdev->interrupt) {
> + case VFIO_INT_MSIX:
> + msix_reset(&vdev->pdev);
> + break;
> + }
This is apparently untested because vdev->interrupt should never be set
to VFIO_INT_MSIX after vfio_disable_interrupts(). Also, you need to
update the normal reset path to call msix_reset() unless it's already
happening via another reset handler. Thanks,
Alex
> +}
> +
> static int vfio_setup_msi(VFIODevice *vdev, int pos)
> {
> uint16_t ctrl;
> @@ -4442,8 +4453,27 @@ int vfio_container_ioctl(AddressSpace *as, int32_t
> groupid,
> switch (req) {
> case VFIO_CHECK_EXTENSION:
> case VFIO_IOMMU_SPAPR_TCE_GET_INFO:
> - case VFIO_EEH_PE_OP:
> break;
> + case VFIO_EEH_PE_OP: {
> + VFIODevice *vdev;
> + struct vfio_eeh_pe_op *arg = (struct vfio_eeh_pe_op *)param;
> +
> + switch (arg->op) {
> + case VFIO_EEH_PE_RESET_HOT:
> + case VFIO_EEH_PE_RESET_FUNDAMENTAL:
> + /*
> + * The MSIx table will be cleaned out by reset. We need
> + * disable it so that it can be reenabled properly. Also,
> + * the cached MSIx table should be cleared as it's not
> + * reflecting the contents in hardware.
> + */
> + QLIST_FOREACH(vdev, &group->device_list, next) {
> + vfio_disable_and_reset_interrupts(vdev);
> + }
> + }
> +
> + break;
> + }
> default:
> /* Return an error on unknown requests */
> error_report("vfio: unsupported ioctl %X", req);
