Hi Jason On Sun, Nov 08, 2020 at 07:41:42PM -0400, Jason Gunthorpe wrote: > On Sun, Nov 08, 2020 at 10:11:24AM -0800, Raj, Ashok wrote: > > > > On (kvm) virtualization the addr/data pair the IRQ domain hands out > > > doesn't work. It is some fake thing. > > > > Is it really some fake thing? I thought the vCPU and vector are real > > for a guest, and VMM ensures when interrupts are delivered they are either. > > It is fake in the sense it is programmed into no hardware. > > It is real in the sense it is an ABI contract with the VMM.
Ah.. its clear now. That clears up my question below as well. > > Yes, no matter what the VMM has to know the guest wants an interrupt > routed in and setup the VMM part of the equation. With SRIOV this is > all done with the MSI trapping. > > > What if the guest creates some addr in the 0xfee... range how do we > > take care of interrupt remapping and such without any VMM assist? > > Not sure I understand this? > My question was based on mis-conception that interrupt entries are directly written by guest OS for mlx*. My concern was about security isolation if guest OS has full control of device interrupt store. I think you clarified it, that interrupts still are marshalled by the VMM and not in direct control of guest OS. That makes my question moot. Cheers, Ashok
