Re: [PATCH 2/2] hw/virtio-pci Added AER capability.

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Aug 13, 2020 at 10:19:31AM +0300, andrew@daynix.com wrote:
> From: Andrew <andrew@daynix.com>
> 
> Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1857668
> Added AER capability for virtio-pci devices.
> Also added property for devices, by default AER is enabled.
> 
> Signed-off-by: Andrew Melnychenko <andrew@daynix.com>

Well AER is pci express only. I suspect you need to limit
this to express, fail on pci.




> ---
>  hw/virtio/virtio-pci.c | 16 ++++++++++++++++
>  hw/virtio/virtio-pci.h |  4 ++++
>  2 files changed, 20 insertions(+)
> 
> diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
> index 8e02709605..646dfb8a0d 100644
> --- a/hw/virtio/virtio-pci.c
> +++ b/hw/virtio/virtio-pci.c
> @@ -1806,6 +1806,12 @@ static void virtio_pci_realize(PCIDevice *pci_dev, Error **errp)
>           */
>          pci_set_word(pci_dev->config + pos + PCI_PM_PMC, 0x3);
>  
> +        if (proxy->flags & VIRTIO_PCI_FLAG_AER) {
> +            pcie_aer_init(pci_dev, PCI_ERR_VER, last_pcie_cap_offset,
> +                          PCI_ERR_SIZEOF, NULL);
> +            last_pcie_cap_offset += PCI_ERR_SIZEOF;
> +        }
> +
>          if (proxy->flags & VIRTIO_PCI_FLAG_INIT_DEVERR) {
>              /* Init error enabling flags */
>              pcie_cap_deverr_init(pci_dev);
> @@ -1847,7 +1853,15 @@ static void virtio_pci_realize(PCIDevice *pci_dev, Error **errp)
>  
>  static void virtio_pci_exit(PCIDevice *pci_dev)
>  {
> +    VirtIOPCIProxy *proxy = VIRTIO_PCI(pci_dev);
> +    bool pcie_port = pci_bus_is_express(pci_get_bus(pci_dev)) &&
> +                     !pci_bus_is_root(pci_get_bus(pci_dev));
> +
>      msix_uninit_exclusive_bar(pci_dev);
> +    if (proxy->flags & VIRTIO_PCI_FLAG_AER && pcie_port &&
> +        pci_is_express(pci_dev)) {
> +        pcie_aer_exit(pci_dev);
> +    }
>  }
>  
>  static void virtio_pci_reset(DeviceState *qdev)
> @@ -1900,6 +1914,8 @@ static Property virtio_pci_properties[] = {
>                      VIRTIO_PCI_FLAG_INIT_PM_BIT, true),
>      DEFINE_PROP_BIT("x-pcie-flr-init", VirtIOPCIProxy, flags,
>                      VIRTIO_PCI_FLAG_INIT_FLR_BIT, true),
> +    DEFINE_PROP_BIT("aer", VirtIOPCIProxy, flags,
> +                    VIRTIO_PCI_FLAG_AER_BIT, true),
>      DEFINE_PROP_END_OF_LIST(),
>  };
>

This will break cross version migration. Please disable this for
old machine types.

I am also unsure why it's on by default generally.
It is optional in express spec.


  
> diff --git a/hw/virtio/virtio-pci.h b/hw/virtio/virtio-pci.h
> index e2eaaa9182..4b2491ff15 100644
> --- a/hw/virtio/virtio-pci.h
> +++ b/hw/virtio/virtio-pci.h
> @@ -45,6 +45,7 @@ enum {
>      VIRTIO_PCI_FLAG_INIT_LNKCTL_BIT,
>      VIRTIO_PCI_FLAG_INIT_PM_BIT,
>      VIRTIO_PCI_FLAG_INIT_FLR_BIT,
> +    VIRTIO_PCI_FLAG_AER_BIT,
>  };
>  
>  /* Need to activate work-arounds for buggy guests at vmstate load. */
> @@ -84,6 +85,9 @@ enum {
>  /* Init Function Level Reset capability */
>  #define VIRTIO_PCI_FLAG_INIT_FLR (1 << VIRTIO_PCI_FLAG_INIT_FLR_BIT)
>  
> +/* Advanced Error Reporting capability */
> +#define VIRTIO_PCI_FLAG_AER (1 << VIRTIO_PCI_FLAG_AER_BIT)
> +
>  typedef struct {
>      MSIMessage msg;
>      int virq;
> -- 
> 2.27.0