On Thu, Mar 12, 2015 at 12:04:59PM +1100, David Gibson wrote:
>On Wed, Mar 11, 2015 at 05:11:52PM +1100, 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/vfio/common.c | 6 +++++-
>> hw/vfio/pci.c | 39 +++++++++++++++++++++++++++++++++++++++
>> include/hw/vfio/vfio.h | 3 ++-
>> 3 files changed, 46 insertions(+), 2 deletions(-)
>>
>> diff --git a/hw/vfio/common.c b/hw/vfio/common.c
>> index 148eb53..e3833f4 100644
>> --- a/hw/vfio/common.c
>> +++ b/hw/vfio/common.c
>> @@ -949,8 +949,12 @@ 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:
>> + if (!vfio_container_eeh_event(as, groupid, param)) {
>
>Please use == 0 not !, remembering that !some_function() is the
>success case hurts my brain.
>
Yes, I'll fix it as below.
>> + break;
>> + }
>> + /* fallthru */
>
>It doesn't look like the fallthrough will generate the correct error
>message: it will say "unsupported ioctl" but
>vfio_container_eeh_event() could fail for some other reason.
>
For now, vfio_container_eeh_event() fails when VFIO group can't be
found, which is checked by vfio_container_do_ioctl() as well. However,
it's worthy to have precise message as follows:
case VFIO_EEH_PE_OP:
if (vfio_container_eeh_event(as, groupid, param) != 0) {
error_report("vfio: cannot handle EEH event on group %d\n",
groupid);
}
break;
>> default:
>> /* Return an error on unknown requests */
>> error_report("vfio: unsupported ioctl %X", req);
>> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
>> index 6b80539..8c4a8cb 100644
>> --- a/hw/vfio/pci.c
>> +++ b/hw/vfio/pci.c
>> @@ -3319,6 +3319,45 @@ static void
>> vfio_unregister_req_notifier(VFIOPCIDevice *vdev)
>> vdev->req_enabled = false;
>> }
>>
>> +int vfio_container_eeh_event(AddressSpace *as, int32_t groupid,
>> + struct vfio_eeh_pe_op *op)
>> +{
>> + VFIOGroup *group;
>> + VFIODevice *vbasedev;
>> + VFIOPCIDevice *vdev;
>> +
>> + group = vfio_get_group(groupid, as);
>> + if (!group) {
>> + vfio_put_group(group);
>
>Is vfio_put_group(NULL) really what you want?
>
No, it should be dropped.
Thanks,
Gavin
>> + error_report("vfio: group %d not found\n", groupid);
>> + return -1;
>> + }
>> +
>> + switch (op->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(vbasedev, &group->device_list, next) {
>> + vdev = container_of(vbasedev, VFIOPCIDevice, vbasedev);
>> + if (msix_enabled(&vdev->pdev)) {
>> + vfio_disable_msix(vdev);
>> + }
>> +
>> + msix_reset(&vdev->pdev);
>> + }
>> +
>> + break;
>> + }
>> +
>> + vfio_put_group(group);
>> + return 0;
>> +}
>> +
>> static int vfio_initfn(PCIDevice *pdev)
>> {
>> VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev);
>> diff --git a/include/hw/vfio/vfio.h b/include/hw/vfio/vfio.h
>> index 0b26cd8..99528a3 100644
>> --- a/include/hw/vfio/vfio.h
>> +++ b/include/hw/vfio/vfio.h
>> @@ -5,5 +5,6 @@
>>
>> extern int vfio_container_ioctl(AddressSpace *as, int32_t groupid,
>> int req, void *param);
>> -
>> +extern int vfio_container_eeh_event(AddressSpace *as, int32_t groupid,
>> + struct vfio_eeh_pe_op *op);
>> #endif
>
>--
>David Gibson | I'll have my music baroque, and my code
>david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
> | _way_ _around_!
>http://www.ozlabs.org/~dgibson
