tools/testing/selftests/kvm/x86/max_vcpuid_cap_test.c
Source file repositories/reference/linux-study-clean/tools/testing/selftests/kvm/x86/max_vcpuid_cap_test.c
File Facts
- System
- Linux kernel
- Corpus path
tools/testing/selftests/kvm/x86/max_vcpuid_cap_test.c- Extension
.c- Size
- 1894 bytes
- Lines
- 63
- Domain
- Support Tooling And Documentation
- Bucket
- tools
- Inferred role
- Support Tooling And Documentation: implementation source
- Status
- source implementation candidate
Why This File Exists
Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
kvm_util.h
Detected Declarations
function Copyright
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0-only
/*
* maximum APIC ID capability tests
*
* Copyright (C) 2022, Intel, Inc.
*
* Tests for getting/setting maximum APIC ID capability
*/
#include "kvm_util.h"
#define MAX_VCPU_ID 2
int main(int argc, char *argv[])
{
struct kvm_vm *vm;
int ret;
vm = vm_create_barebones();
/* Get KVM_CAP_MAX_VCPU_ID cap supported in KVM */
ret = vm_check_cap(vm, KVM_CAP_MAX_VCPU_ID);
/* Try to set KVM_CAP_MAX_VCPU_ID beyond KVM cap */
ret = __vm_enable_cap(vm, KVM_CAP_MAX_VCPU_ID, ret + 1);
TEST_ASSERT(ret < 0,
"Setting KVM_CAP_MAX_VCPU_ID beyond KVM cap should fail");
/* Test BOOT_CPU_ID interaction (MAX_VCPU_ID cannot be lower) */
if (kvm_has_cap(KVM_CAP_SET_BOOT_CPU_ID)) {
vm_ioctl(vm, KVM_SET_BOOT_CPU_ID, (void *)MAX_VCPU_ID);
/* Try setting KVM_CAP_MAX_VCPU_ID below BOOT_CPU_ID */
ret = __vm_enable_cap(vm, KVM_CAP_MAX_VCPU_ID, MAX_VCPU_ID - 1);
TEST_ASSERT(ret < 0,
"Setting KVM_CAP_MAX_VCPU_ID below BOOT_CPU_ID should fail");
}
/* Set KVM_CAP_MAX_VCPU_ID */
vm_enable_cap(vm, KVM_CAP_MAX_VCPU_ID, MAX_VCPU_ID);
/* Try to set KVM_CAP_MAX_VCPU_ID again */
ret = __vm_enable_cap(vm, KVM_CAP_MAX_VCPU_ID, MAX_VCPU_ID + 1);
TEST_ASSERT(ret < 0,
"Setting KVM_CAP_MAX_VCPU_ID multiple times should fail");
/* Create vCPU with id beyond KVM_CAP_MAX_VCPU_ID cap */
ret = __vm_ioctl(vm, KVM_CREATE_VCPU, (void *)MAX_VCPU_ID);
TEST_ASSERT(ret < 0, "Creating vCPU with ID > MAX_VCPU_ID should fail");
/* Create vCPU with bits 63:32 != 0, but an otherwise valid id */
ret = __vm_ioctl(vm, KVM_CREATE_VCPU, (void *)(1L << 32));
TEST_ASSERT(ret < 0, "Creating vCPU with ID[63:32] != 0 should fail");
/* Create vCPU with id within bounds */
ret = __vm_ioctl(vm, KVM_CREATE_VCPU, (void *)0);
TEST_ASSERT(ret >= 0, "Creating vCPU with ID 0 should succeed");
close(ret);
kvm_vm_free(vm);
return 0;
}
Annotation
- Immediate include surface: `kvm_util.h`.
- Detected declarations: `function Copyright`.
- Atlas domain: Support Tooling And Documentation / tools.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.