On Wed, Jul 22, 2020 at 07:17:22PM +0300, Maxim Levitsky wrote:
> Curently it is possible to hotplug a device and then immediatly
> hotunplug it before the OS notices, and that will result
> in missed unplug event since we can only send one attention button event.
>
> Moreover the device will stuck in unplugging state forever.
>
> Error out in such cases and rely on the caller (e.g libvirt) to retry
> the unplug a bit later
>
> Signed-off-by: Maxim Levitsky <mlevi...@redhat.com>
> ---
> hw/pci/pcie.c | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
> diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c
> index 5b48bae0f6..9e836cf2f4 100644
> --- a/hw/pci/pcie.c
> +++ b/hw/pci/pcie.c
> @@ -402,6 +402,17 @@ static void pcie_cap_slot_plug_common(PCIDevice
> *hotplug_dev, DeviceState *dev,
> */
> error_setg_errno(errp, EBUSY, "slot is electromechanically locked");
> }
> +
> + if (sltsta & PCI_EXP_SLTSTA_ABP) {
> + /*
> + * Attention button is pressed, thus we can't send another
> + * hotpplug event
typo
> + */
> + error_setg_errno(errp, EBUSY,
> + "attention button is already pressed, can't "
> + "send another hotplug event");
> + }
> +
> }
It would be neater if we could queue the event up
in qemu. Alternatively - can we clean up the unhandled
event so guest does not even notice the device
briefly appeared?
>
> void pcie_cap_slot_pre_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev,
> --
> 2.26.2
