On Tue, Aug 25, 2015 at 4:57 PM, Pavel Fedin <p.fedin@xxxxxxxxxxx> wrote: > Hello! Where are you? I'd like to take a look at your code. Sorry, I am occupied with other tasks for next 2 weeks, After that I will look into this. > > Kind regards, > Pavel Fedin > Expert Engineer > Samsung Electronics Research center Russia > > >> -----Original Message----- >> From: Vijay Kilari [mailto:vijay.kilari@xxxxxxxxx] >> Sent: Tuesday, August 11, 2015 6:16 PM >> To: Pavel Fedin >> Cc: kvmarm@xxxxxxxxxxxxxxxxxxxxx; Christoffer Dall; Alex Bennée >> Subject: Re: KVM Live migration with GICv3 >> >> On Tue, Aug 11, 2015 at 12:11 PM, Pavel Fedin <p.fedin@xxxxxxxxxxx> wrote: >> > Hello! >> > >> >> I have prototyped Live migration with GICv3. >> > >> > This is interesting of course, i will need this for my project too and i was also going to take a look at >> this later. >> > >> >> For this I have made following changes >> >> >> >> 1) Save and Restore of GICv3 registers in QEMU. >> >> - For GICv2, QEMU is saving/restoring GICD, GICC registers. For GICv3, >> >> we have to save/restore GICD, GICR and ICC registers. >> >> However ICC registers are system registers which cannot be >> >> accessed @ EL0 level (SRE=1). So these ICC registers should be >> >> accessed as mmio registers by QEMU, for this we have to add ioctl to >> >> access ICC @ EL1 level similar to GICC registers of GICv2. >> > >> > Sorry, your description is a bit fuzzy. What ioctl's did you have to add and why? >> > The kernel already has KVM_GET_ONE_REG and KVM_SET_ONE_REG ioctl's. And they can be used >> to access anything inside the VM, including system registers. I believe you would need only to >> implement handlers for GICv3 registers. >> >> I mean CPU interface registers GICC* defined for vgicv2 under >> "vgic_cpu_ranges[]" in >> virt/kvm/arm/vgic-v2-emul.c needs to be saved and restored for vgicv3 as well. >> So to access vgic_cpu_ranges[] for vgicv3, we need to register device >> for CPU registers space >> similar to gicv2 in QEMU for gicv3. >> >> ----------------------------------------------------------------------------------------- >> memory_region_init_reservation(&s->cpuiomem[0], OBJECT(s), >> "kvm-gic_cpu", 0x1000); >> sysbus_init_mmio(sbd, &s->cpuiomem[0]); >> kvm_arm_register_device(&s->cpuiomem[0], >> (KVM_ARM_DEVICE_VGIC_V3 << KVM_ARM_DEVICE_ID_SHIFT) >> | KVM_VGIC_V3_ADDR_TYPE_CPU, >> KVM_DEV_ARM_VGIC_GRP_ADDR, >> KVM_VGIC_V3_ADDR_TYPE_CPU, >> s->dev_fd); >> ------------------------------------------------------------------------------------------- >> >> Anyway, I will send RFC patches. >> >> > >> >> Please provide your initial feedback. >> > >> > Would be nice to take a look at patches. >> > >> >> I am attending KVM-forum next week @ Seattle. We can discuss there as well. >> > >> > I would love to go there, and my company wanted to send me there. But it appears to be extremely >> difficult for a tech specialist from Russia to get a US visa. They are still considering me and the time is >> running out, so i'm unlikely to attend, unfortunately. >> > >> > Kind regards, >> > Pavel Fedin >> > Expert Engineer >> > Samsung Electronics Research center Russia >> > >> > > _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
