On Thu, Oct 22, 2020 at 02:40:26PM +0300, Marcel Apfelbaum wrote:
> From: Marcel Apfelbaum <mar...@redhat.com>
>
> During PCIe Root Port's transition from Power-Off to Power-ON (or vice-versa)
> the "Slot Control Register" has the "Power Indicator Control"
> set to "Blinking" expressing a "power transition" mode.
>
> Any hotplug operation during the "power transition" mode is not permitted
> or at least not expected by the Guest OS leading to strange failures.
>
> Detect and refuse hotplug operations in such case.
>
> Signed-off-by: Marcel Apfelbaum <marcel.apfelb...@gmail.com>
> ---
> hw/pci/pcie.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c
> index 5b48bae0f6..2fe5c1473f 100644
> --- a/hw/pci/pcie.c
> +++ b/hw/pci/pcie.c
> @@ -410,6 +410,7 @@ void pcie_cap_slot_pre_plug_cb(HotplugHandler
> *hotplug_dev, DeviceState *dev,
> PCIDevice *hotplug_pdev = PCI_DEVICE(hotplug_dev);
> uint8_t *exp_cap = hotplug_pdev->config + hotplug_pdev->exp.exp_cap;
> uint32_t sltcap = pci_get_word(exp_cap + PCI_EXP_SLTCAP);
> + uint32_t sltctl = pci_get_word(exp_cap + PCI_EXP_SLTCTL);
>
> /* Check if hot-plug is disabled on the slot */
> if (dev->hotplugged && (sltcap & PCI_EXP_SLTCAP_HPC) == 0) {
> @@ -418,6 +419,12 @@ void pcie_cap_slot_pre_plug_cb(HotplugHandler
> *hotplug_dev, DeviceState *dev,
> return;
> }
>
> + if ((sltctl & PCI_EXP_SLTCTL_PIC) == PCI_EXP_SLTCTL_PWR_IND_BLINK) {
> + error_setg(errp, "Hot-plug failed: %s is in Power Transition",
> + DEVICE(hotplug_pdev)->id);
> + return;
> + }
> +
> pcie_cap_slot_plug_common(PCI_DEVICE(hotplug_dev), dev, errp);
> }
I wonder if hw/pci/shpc.c is free from this issue?
Roman.
