Re: [RESEND PATCH v2 4/4] PCI: Add support for enforcing all MMIO BARs to be page aligned

2016-06-20 Thread Yongji Xie
On 2016/6/21 10:26, Bjorn Helgaas wrote: On Thu, Jun 02, 2016 at 01:46:51PM +0800, Yongji Xie wrote: When vfio passthrough a PCI device of which MMIO BARs are smaller than PAGE_SIZE, guest will not handle the mmio accesses to the BARs which leads to mmio emulations in host. This is because vfi

Re: [RESEND PATCH v2 4/4] PCI: Add support for enforcing all MMIO BARs to be page aligned

2016-06-20 Thread Bjorn Helgaas
On Thu, Jun 02, 2016 at 01:46:51PM +0800, Yongji Xie wrote: > When vfio passthrough a PCI device of which MMIO BARs are > smaller than PAGE_SIZE, guest will not handle the mmio > accesses to the BARs which leads to mmio emulations in host. > > This is because vfio will not allow to passthrough one

[RESEND PATCH v2 4/4] PCI: Add support for enforcing all MMIO BARs to be page aligned

2016-06-01 Thread Yongji Xie
When vfio passthrough a PCI device of which MMIO BARs are smaller than PAGE_SIZE, guest will not handle the mmio accesses to the BARs which leads to mmio emulations in host. This is because vfio will not allow to passthrough one BAR's mmio page which may be shared with other BARs. Otherwise, there