On Mon, Oct 05, 2015 at 01:36:35PM +0300, Vlad Zolotarov wrote: > >And then there's the issue of why we even need this, why not just > >write a whole new driver for this, like the previous driver did (which > >also used ioctls, yes, I didn't have the chance to object to that before > >everyone else did...) > > Which "previous driver" do u refer here? > IMHO writing something instead of UIO (not just uio_pci_generic) seems like > an overkill for solving this issue. Supporting MSI-X interrupts seem like a > very beneficial feature for uio_pci_generic and it's really not _THAT_ > complicated API - just look at VFIO for a comparison... ;)
Except most things VFIO does is actually there for security. Which, for a device that can do DMA and isn't even behind an IOMMU, sounds like a pretty big deal actually. > uio_pci_generic is clearly missing this important feature. And creating > another user space driver infrastructure just to add it seems extremely > unjustified. uio_pci_generic was always intended to be used with extremely simple devices which don't do DMA, or where someone else has set up the IOMMU (like kvm does with CONFIG_KVM_DEVICE_ASSIGNMENT). We need to be much more careful with MSI if there's no IOMMU. -- MST -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
