On Mon, 7 Nov 2011 23:14:14 +0200, "Michael S. Tsirkin" <mst@xxxxxxxxxx> wrote: > On Mon, Nov 07, 2011 at 03:46:23PM +1030, Rusty Russell wrote: > > So far, the only three things make sense to have in a capability list: > > MSI-X, the upper 32 feature bits, and the per-device config. > > You mean the queue # to MSI-X vector mapping? Yep. > One thing to remember is that it must be in the same type of BAR as > the queue selection, since by PCI rules MMIO writes aren't I think > ordered with PIO writes (it doesn't matter with KVM but might > with another hypervisor). OK, I'm slowly getting up to speed. Next dumb q: Sasha, why did you introduce the idea of a separate virtio-pci capability list, rather than just using PCI capabilities directly? ie. instead of VIRTIO_PCI_C_LAYOUT, have VIRTIO_PCI_CORE, VIRTIO_PCI_MSIX, VIRTIO_PCI_DEV_SPECIFIC? Is it because we really want this stuff outside the PCI configuration space? Even so, should we just use the PCI cap list, and have each cap entry just contain a BIR & offset? Thanks, Rusty. _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
