>>> On 17.03.15 at 06:26, <mja...@caviumnetworks.com> wrote: > In drivers/xen/pci.c on notification BUS_NOTIFY_ADD_DEVICE dom0 issues a > hypercall to inform xen that a new pci device has been added. > If we were to inform xen about a new pci bus that is added there are 2 ways > a) Issue the hypercall from drivers/pci/probe.c > b) When a new device is found (BUS_NOTIFY_ADD_DEVICE) issue > PHYSDEVOP_pci_device_add hypercall to xen, if xen does not finds that > segment number (s_bdf), it will return an error > SEG_NO_NOT_FOUND. After that the linux xen code could issue the > PHYSDEVOP_pci_host_bridge_add hypercall. > > I think (b) can be done with minimal code changes. What do you think ?
I'm pretty sure (a) would even be refused by the maintainers, unless there already is a notification being sent. As to (b) - kernel code could keep track of which segment/bus pairs it informed Xen about, and hence wouldn't even need to wait for an error to be returned from the device-add request (which in your proposal would need to be re- issued after the host-bridge-add). Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
