>>>> 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 > True, if such a machine existed, then this patch wouldn't detect it. I don't > think we support anything like that in mainline at the moment, but the > following additional diff should solve the problem, no? > > diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c > index fa9a95b3ed19..476d3bf540a8 100644 > --- a/virt/kvm/arm/vgic.c > +++ b/virt/kvm/arm/vgic.c > @@ -1539,6 +1539,14 @@ int kvm_vgic_hyp_init(void) > goto out_unmap; > } > > + if (!PAGE_ALIGNED(resource_size(&vcpu_res))) { > + kvm_err("GICV size 0x%llx not a multiple of page size 0x%lx\n", > + (unsigned long long)resource_size(&vcpu_res), > + PAGE_SIZE); > + ret = -ENXIO; > + goto out_unmap; > + } > + > vgic_vcpu_base = vcpu_res.start; > > kvm_info("%s@%llx IRQ%d\n", vgic_node->name, This would break with my SOC device tree which looks like this. Note this device tree works just fine without checks. gic: interrupt-controller@e1101000 { compatible = "arm,gic-400-v2m"; #interrupt-cells = <3>; #address-cells = <0>; interrupt-controller; msi-controller; reg = <0x0 0xe1110000 0 0x1000>, /* gic dist */ <0x0 0xe112f000 0 0x2000>, /* gic cpu */ <0x0 0xe114f000 0 0x2000>, /* gic virtual ic*/ <0x0 0xe116f000 0 0x2000>, /* gic virtual cpu*/ <0x0 0xe1180000 0 0x1000>; /* gic msi */ interrupts = <1 8 0xf04>; }; -- 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