Hi Alex,
On 2016/6/30 9:45, Zhou Jie wrote:
Hi Alex,
On 2016/6/30 2:22, Alex Williamson wrote:
On Wed, 29 Jun 2016 16:54:05 +0800
Zhou Jie <address@hidden> wrote:
Hi Alex,
And yet we have struct pci_dev.broken_intx_masking and we test for
working DisINTx via pci_intx_mask_supported() rather than simply
looking for a PCIe device. Some devices are broken and some simply
don't follow the spec, so you're going to need to deal with that or
exclude those devices.
For those devices I have no way to disable the INTx.
disable_irq()? Clearly vfio-pci already manages these types of devices
and can disable INTx. This is why I keep suggesting that maybe tearing
the interrupt setup down completely is a more complete and reliable
approach than masking in the command register. Unless we're going to
exclude such devices from supporting this mode (which I don't condone),
we must deal with them.
Thank you for tell me that.
Yes, I can use disable_irq to disable the pci device irq.
But should I enable the irq after reset?
I will dig into it.
I will alter the VFIO driver like following.
During err occurs and resume:
1. Make config space read only.
2. Disable INTx/MSI Interrupt.
3. Do nothing for bar regions.
The following code will be modified.
1. vfio_pci_ioctl
add a flag in vfio_device_info for workable_state support
return workable_state in "struct vfio_pci_device" when user get info
2. vfio_pci_ioctl
During err occurs and resume:
if (cmd == VFIO_DEVICE_SET_IRQS || VFIO_DEVICE_RESET
|| VFIO_DEVICE_GET_PCI_HOT_RESET_INFO || VFIO_DEVICE_PCI_HOT_RESET)
block for workable_state clearing
3. vfio_pci_write
During err occurs and resume:
ignore and return 0
4. vfio_pci_aer_err_detected
Set workable_state to false in "struct vfio_pci_device"
Disable INTx:
If Disable INTx is support
disable by PCI_COMMAND
else
disable by disable_irq function
Disable MSI:
disable by clearing the "Bus Master Enable" bit of PCI_COMMAND
5. vfio_pci_aer_resume
Set workable_state to true in "struct vfio_pci_device"
About INTx:
According to the value of "vdev->ctx[0].masked"
to decide whether to enable INTx
About MSI:
After reset the "Bus Master Enable" bit is default to 0.
So user should process this after reset.
Sincerely
Zhou Jie