target/arm: kvm: require KVM_CAP_DEVICE_CTRL

Commit Message

Paolo Bonzini Oct. 24, 2024, 11:31 a.m. UTC

The device control API was added in 2013, assume that it is present.

Signed-off-by: Paolo Bonzini <[e-mail]>
---
 target/arm/kvm_arm.h  | 16 +++++++---------
 hw/intc/arm_gic_kvm.c |  9 +--------
 target/arm/kvm.c      | 17 +++++------------
 3 files changed, 13 insertions(+), 29 deletions(-)

Patch

diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h
index cfaa0d9bc71..02b02b4cd20 100644
--- a/target/arm/kvm_arm.h
+++ b/target/arm/kvm_arm.h
@@ -22,17 +22,15 @@ 
  * @devid: the KVM device ID
  * @group: device control API group for setting addresses
  * @attr: device control API address type
- * @dev_fd: device control device file descriptor (or -1 if not supported)
+ * @dev_fd: device control device file descriptor
  * @addr_ormask: value to be OR'ed with resolved address
  *
- * Remember the memory region @mr, and when it is mapped by the
- * machine model, tell the kernel that base address using the
- * KVM_ARM_SET_DEVICE_ADDRESS ioctl or the newer device control API.  @devid
- * should be the ID of the device as defined by KVM_ARM_SET_DEVICE_ADDRESS or
- * the arm-vgic device in the device control API.
- * The machine model may map
- * and unmap the device multiple times; the kernel will only be told the final
- * address at the point where machine init is complete.
+ * Remember the memory region @mr, and when it is mapped by the machine
+ * model, tell the kernel that base address using the device control API.
+ * @devid should be the ID of the device as defined by  the arm-vgic device
+ * in the device control API.  The machine model may map and unmap the device
+ * multiple times; the kernel will only be told the final address at the
+ * point where machine init is complete.
  */
 void kvm_arm_register_device(MemoryRegion *mr, uint64_t devid, uint64_t group,
                              uint64_t attr, int dev_fd, uint64_t addr_ormask);
diff --git a/hw/intc/arm_gic_kvm.c b/hw/intc/arm_gic_kvm.c
index 53defee7d59..e2a73337b1e 100644
--- a/hw/intc/arm_gic_kvm.c
+++ b/hw/intc/arm_gic_kvm.c
@@ -547,17 +547,10 @@  static void kvm_arm_gic_realize(DeviceState *dev, Error **errp)
                               KVM_DEV_ARM_VGIC_CTRL_INIT, NULL, true,
                               &error_abort);
         }
-    } else if (kvm_check_extension(kvm_state, KVM_CAP_DEVICE_CTRL)) {
+    } else {
         error_setg_errno(errp, -ret, "error creating in-kernel VGIC");
         error_append_hint(errp,
                           "Perhaps the host CPU does not support GICv2?\n");
-    } else if (ret != -ENODEV && ret != -ENOTSUP) {
-        /*
-         * Very ancient kernel without KVM_CAP_DEVICE_CTRL: assume that
-         * ENODEV or ENOTSUP mean "can't create GICv2 with KVM_CREATE_DEVICE",
-         * and that we will get a GICv2 via KVM_CREATE_IRQCHIP.
-         */
-        error_setg_errno(errp, -ret, "error creating in-kernel VGIC");
         return;
     }
 
diff --git a/target/arm/kvm.c b/target/arm/kvm.c
index f1f1b5b375a..7d0dee2e3bb 100644
--- a/target/arm/kvm.c
+++ b/target/arm/kvm.c
@@ -41,6 +41,7 @@ 
 #include "target/arm/gtimer.h"
 
 const KVMCapabilityInfo kvm_arch_required_capabilities[] = {
+    KVM_CAP_INFO(DEVICE_CTRL),
     KVM_CAP_LAST_INFO
 };
 
@@ -675,19 +676,11 @@  static void kvm_arm_set_device_addr(KVMDevice *kd)
 {
     struct kvm_device_attr *attr = &kd->kdattr;
     int ret;
+    uint64_t addr = kd->kda.addr;
 
-    /* If the device control API is available and we have a device fd on the
-     * KVMDevice struct, let's use the newer API
-     */
-    if (kd->dev_fd >= 0) {
-        uint64_t addr = kd->kda.addr;
-
-        addr |= kd->kda_addr_ormask;
-        attr->addr = (uintptr_t)&addr;
-        ret = kvm_device_ioctl(kd->dev_fd, KVM_SET_DEVICE_ATTR, attr);
-    } else {
-        ret = kvm_vm_ioctl(kvm_state, KVM_ARM_SET_DEVICE_ADDR, &kd->kda);
-    }
+    addr |= kd->kda_addr_ormask;
+    attr->addr = (uintptr_t)&addr;
+    ret = kvm_device_ioctl(kd->dev_fd, KVM_SET_DEVICE_ATTR, attr);
 
     if (ret < 0) {
         fprintf(stderr, "Failed to set device address: %s\n",