On 08/20/2014 07:52 PM, 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 | 24 ++++++++++++++++++++++++
> 1 file changed, 24 insertions(+)
>
> diff --git a/hw/misc/vfio.c b/hw/misc/vfio.c
> index 1a3e7eb..3cf7f02 100644
> --- a/hw/misc/vfio.c
> +++ b/hw/misc/vfio.c
> @@ -4424,6 +4424,8 @@ int vfio_container_ioctl(AddressSpace *as, int32_t
> groupid,
> {
> VFIOGroup *group;
> VFIOContainer *container;
> + VFIODevice *vdev;
> + struct vfio_eeh_pe_op *arg;
> int ret = -1;
>
> group = vfio_get_group(groupid, as);
> @@ -4442,7 +4444,29 @@ int vfio_container_ioctl(AddressSpace *as, int32_t
> groupid,
> switch (req) {
> case VFIO_CHECK_EXTENSION:
> case VFIO_IOMMU_SPAPR_TCE_GET_INFO:
> + break;
> case 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) {
> + if (msix_enabled(&vdev->pdev)) {
> + vfio_disable_msix(vdev);
> + }
> +
> + msix_reset(&vdev->pdev);
> + }
> +
> + break;
> + }
This has to be done in spapr_pci_vfio (but we do not have there access to
vfio_disable_msix) or in the way that x86 would benefit from too but in
this case yes, we need an opinion from Alex (Williamson)...
> +
> break;
> default:
> /* Return an error on unknown requests */
>
--
Alexey
