Hi Zenghui, On 9/24/20 3:42 PM, Zenghui Yu wrote: > Hi Eric, > > On 2020/3/21 0:19, Eric Auger wrote: >> The VFIO API was enhanced to support nested stage control: a bunch of >> new iotcls, one DMA FAULT region and an associated specific IRQ. >> >> Let's document the process to follow to set up nested mode. >> >> Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx> > > [...] > >> +The userspace must be prepared to receive faults. The VFIO-PCI device >> +exposes one dedicated DMA FAULT region: it contains a ring buffer and >> +its header that allows to manage the head/tail indices. The region is >> +identified by the following index/subindex: >> +- VFIO_REGION_TYPE_NESTED/VFIO_REGION_SUBTYPE_NESTED_DMA_FAULT >> + >> +The DMA FAULT region exposes a VFIO_REGION_INFO_CAP_PRODUCER_FAULT >> +region capability that allows the userspace to retrieve the ABI version >> +of the fault records filled by the host. > > Nit: I don't see this capability in the code. Thank you very much for the review. I am late doing the respin but I will take into account all your comments. Thanks! Eric > > > Thanks, > Zenghui >
