ppc/openpic: create a new openpic device and reattach mem region on coco reset
For confidential guests during the reset process, the old KVM VM file descriptor is closed and a new one is created. When a new file descriptor is created, a new openpic device needs to be created against this new KVM VM file descriptor as well. Additionally, existing memory region needs to be reattached to this new openpic device and proper CPU attributes set associating new file descriptor. This change makes this happen with the help of a callback handler that gets called when the KVM VM file descriptor changes as a part of the confidential guest reset process. Reviewed-by: Bernhard Beschow <shentey@gmail.com> Signed-off-by: Ani Sinha <anisinha@redhat.com> Link: https://lore.kernel.org/r/20260225035000.385950-30-anisinha@redhat.com Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Ani Sinha committed
Feb 25, 2026 at 09:19 UTC
c320bd40f7cddc2a755ad3eac4ee2088a7d466cd
1 file changed
+88
-24
hw/intc/openpic_kvm.c
+88
-24
@@ -49,6 +49,7 @@ struct KVMOpenPICState {
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uint32_t fd;
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uint32_t model;
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hwaddr mapped;
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+ NotifierWithReturn vmfd_change_notifier;
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};
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static void kvm_openpic_set_irq(void *opaque, int n_IRQ, int level)
@@ -114,6 +115,88 @@ static const MemoryRegionOps kvm_openpic_mem_ops = {
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},
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};
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+static int kvm_openpic_setup(KVMOpenPICState *opp, Error **errp)
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+{
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+ int kvm_openpic_model;
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+ struct kvm_create_device cd = {0};
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+ KVMState *s = kvm_state;
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+ int ret;
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+
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+ switch (opp->model) {
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+ case OPENPIC_MODEL_FSL_MPIC_20:
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+ kvm_openpic_model = KVM_DEV_TYPE_FSL_MPIC_20;
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+ break;
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+
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+ case OPENPIC_MODEL_FSL_MPIC_42:
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+ kvm_openpic_model = KVM_DEV_TYPE_FSL_MPIC_42;
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+ break;
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+
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+ default:
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+ error_setg(errp, "Unsupported OpenPIC model %" PRIu32, opp->model);
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+ return -1;
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+ }
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+
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+ cd.type = kvm_openpic_model;
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+ ret = kvm_vm_ioctl(s, KVM_CREATE_DEVICE, &cd);
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+ if (ret < 0) {
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+ error_setg(errp, "Can't create device %d: %s",
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+ cd.type, strerror(errno));
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+ return -1;
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+ }
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+ opp->fd = cd.fd;
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+
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+ return 0;
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+}
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+
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+static int kvm_openpic_handle_vmfd_change(NotifierWithReturn *notifier,
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+ void *data, Error **errp)
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+{
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+ KVMOpenPICState *opp = container_of(notifier, KVMOpenPICState,
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+ vmfd_change_notifier);
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+ uint64_t reg_base;
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+ struct kvm_device_attr attr;
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+ CPUState *cs;
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+ int ret;
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+
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+ /* we are not interested in pre vmfd change notification */
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+ if (((VmfdChangeNotifier *)data)->pre) {
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+ return 0;
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+ }
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+
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+ /* close the old descriptor */
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+ close(opp->fd);
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+
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+ if (kvm_openpic_setup(opp, errp) < 0) {
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+ return -1;
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+ }
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+
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+ if (!opp->mapped) {
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+ return 0;
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+ }
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+
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+ reg_base = opp->mapped;
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+ attr.group = KVM_DEV_MPIC_GRP_MISC;
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+ attr.attr = KVM_DEV_MPIC_BASE_ADDR;
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+ attr.addr = (uint64_t)(unsigned long)®_base;
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+
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+ ret = ioctl(opp->fd, KVM_SET_DEVICE_ATTR, &attr);
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+ if (ret < 0) {
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+ error_setg(errp, "%s: %s %" PRIx64, __func__,
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+ strerror(errno), reg_base);
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+ return -1;
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+ }
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+
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+ CPU_FOREACH(cs) {
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+ ret = kvm_vcpu_enable_cap(cs, KVM_CAP_IRQ_MPIC, 0, opp->fd,
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+ kvm_arch_vcpu_id(cs));
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+ if (ret < 0) {
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+ return ret;
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+ }
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+ }
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+
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+ return 0;
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+}
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+
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static void kvm_openpic_region_add(MemoryListener *listener,
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MemoryRegionSection *section)
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{
@@ -197,36 +280,14 @@ static void kvm_openpic_realize(DeviceState *dev, Error **errp)
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SysBusDevice *d = SYS_BUS_DEVICE(dev);
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KVMOpenPICState *opp = KVM_OPENPIC(dev);
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KVMState *s = kvm_state;
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- int kvm_openpic_model;
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- struct kvm_create_device cd = {0};
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- int ret, i;
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+ int i;
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if (!kvm_check_extension(s, KVM_CAP_DEVICE_CTRL)) {
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error_setg(errp, "Kernel is lacking Device Control API");
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return;
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}
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- switch (opp->model) {
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- case OPENPIC_MODEL_FSL_MPIC_20:
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- kvm_openpic_model = KVM_DEV_TYPE_FSL_MPIC_20;
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- break;
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-
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- case OPENPIC_MODEL_FSL_MPIC_42:
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- kvm_openpic_model = KVM_DEV_TYPE_FSL_MPIC_42;
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- break;
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-
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- default:
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- error_setg(errp, "Unsupported OpenPIC model %" PRIu32, opp->model);
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- return;
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- }
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-
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- cd.type = kvm_openpic_model;
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- ret = kvm_vm_ioctl(s, KVM_CREATE_DEVICE, &cd);
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- if (ret < 0) {
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- error_setg_errno(errp, errno, "Can't create device %d", cd.type);
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- return;
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- }
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- opp->fd = cd.fd;
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+ kvm_openpic_setup(opp, errp);
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sysbus_init_mmio(d, &opp->mem);
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qdev_init_gpio_in(dev, kvm_openpic_set_irq, OPENPIC_MAX_IRQ);
@@ -235,6 +296,9 @@ static void kvm_openpic_realize(DeviceState *dev, Error **errp)
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opp->mem_listener.region_del = kvm_openpic_region_del;
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opp->mem_listener.name = "openpic-kvm";
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memory_listener_register(&opp->mem_listener, &address_space_memory);
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+ opp->vmfd_change_notifier.notify =
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+ kvm_openpic_handle_vmfd_change;
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+ kvm_vmfd_add_change_notifier(&opp->vmfd_change_notifier);
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/* indicate pic capabilities */
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msi_nonbroken = true;