Matthew Wilcox wrote: > On Fri, Feb 20, 2009 at 02:54:42PM +0800, Yu Zhao wrote: >> +config PCI_IOV >> + bool "PCI IOV support" >> + depends on PCI >> + select PCI_MSI > > My understanding is that having 'select' of a config symbol that the > user can choose is bad. I think we should probably make this 'depends > on PCI_MSI'. Ack. > PCI MSI can also be disabled at runtime (and Fedora do by default). > Since SR-IOV really does require MSI, we need to put in a runtime check > to see if pci_msi_enabled() is false. > > We don't depend on PCIEPORTBUS (a horribly named symbol). Should we? > SR-IOV is only supported for PCI Express machines. I'm not sure of the > right answer here, but I thought I should raise the question. > >> + help >> + PCI-SIG I/O Virtualization (IOV) Specifications support. >> + Single Root IOV: allows the Physical Function driver to enable >> + the hardware capability, so the Virtual Function is accessible >> + via the PCI Configuration Space using its own Bus, Device and >> + Function Numbers. Each Virtual Function also has the PCI Memory >> + Space to map the device specific register set. Too spec. and implementation specific for users. > I'm not convinced this is the most helpful we could be to the user who's > configuring their own kernel. How about something like this? (Randy, I > particularly look to you to make my prose less turgid). > > help > IO Virtualisation is a PCI feature supported by some devices z ;) > which allows you to create virtual PCI devices and assign them > to guest OSes. This option needs to be selected in the host > or Dom0 kernel, but does not need to be selected in the guest > or DomU kernel. If you don't know whether your hardware supports > it, you can check by using lspci to look for the SR-IOV capability. > > If you have no idea what any of that means, it is safe to > answer 'N' here. That's certainly more readable and user-friendly. I don't know what else it needs. Looks good to me. ~Randy -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
