On 24 July 2014 20:55, Will Deacon <will.deacon@xxxxxxx> wrote: > Again, that can be solved by introduced Marc's attr for determining the > GICV offset within the 64k page. I don't think that's -stable material. Agreed that we don't want to put Marc's patchset in -stable (and that without it systems with GICV in their host devicetree at pagebase+60K are unusable, so we're not actually regressing anything if we put this into stable). But... >> I can't think of any way of determining whether a particular >> system gets this right or wrong automatically, which suggests >> perhaps we need to allow the device tree to specify that the >> GICV is 64k-page-safe... > > When we support such systems, I also think we'll need a device-tree change. > My main concern right now is stopping the ability to hose the entire machine > by trying to instantiate a virtual GIC. ...I don't see how your patch prevents instantiating a VGIC and hosing the machine on a system where the 64K with the GICV registers in it goes [GICV registers] [machine blows up if you read this] 0K 8K 64K Whether the 64K page contains Bad Stuff is completely orthogonal to whether the device tree offset the host has for the GICV is 0K, 60K or anything in between. What you should be checking for is "is this system design broken?", which is probably a device tree attribute. thanks -- PMM -- 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
