> -----Original Message----- > From: Roedel, Joerg [mailto:Joerg.Roedel@xxxxxxx] > Sent: Monday, September 12, 2011 6:06 PM > To: Sethi Varun-B16395 > Cc: Joerg Roedel; Greg KH; iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx; Alex > Williamson; Ohad Ben-Cohen; David Woodhouse; David Brown; > kvm@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx > Subject: Re: [PATCH 02/10] Driver core: Add iommu_ops to bus_type > > On Mon, Sep 12, 2011 at 08:08:41AM -0400, Sethi Varun-B16395 wrote: > > > The IOMMUs are usually devices on the bus itself, so they are > > > initialized after the bus is set up and the devices on it are > > > populated. So the function can not be called on bus initialization > > > because the IOMMU is not ready at this point. > > Well, at what point would the add_device_group (referring to patch set > posted by Alex) call back be invoked? > > The details are up to Alex Williamson. One option is to register a > notifier for the bus in the iommu_bus_init() function and react to its > notifications. > I think in the end we will have a number of additional call-backs in the > iommu_ops which are called by the notifier (or from the driver-core > directly) to handle actions like added or removed devices. All the > infrastructure for that which is implemented in the iommu-drivers today > will then be in the iommu-core code. I am not sure If I understand this, but as per your earlier statement iommu is a device on the bus and its initialization would happen when bus is set up and devices are populated. So, when would device notifier call an iommu call back? -Varun -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
