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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * kvm_create_max_vcpus4 *5 * Copyright (C) 2019, Google LLC.6 *7 * Test for KVM_CAP_MAX_VCPUS and KVM_CAP_MAX_VCPU_ID.8 */9#include <fcntl.h>10#include <stdio.h>11#include <stdlib.h>12#include <string.h>13#include <sys/resource.h>14 15#include "test_util.h"16 17#include "kvm_util.h"18#include "asm/kvm.h"19#include "linux/kvm.h"20 21void test_vcpu_creation(int first_vcpu_id, int num_vcpus)22{23 struct kvm_vm *vm;24 int i;25 26 pr_info("Testing creating %d vCPUs, with IDs %d...%d.\n",27 num_vcpus, first_vcpu_id, first_vcpu_id + num_vcpus - 1);28 29 vm = vm_create_barebones();30 31 for (i = first_vcpu_id; i < first_vcpu_id + num_vcpus; i++)32 /* This asserts that the vCPU was created. */33 __vm_vcpu_add(vm, i);34 35 kvm_vm_free(vm);36}37 38int main(int argc, char *argv[])39{40 int kvm_max_vcpu_id = kvm_check_cap(KVM_CAP_MAX_VCPU_ID);41 int kvm_max_vcpus = kvm_check_cap(KVM_CAP_MAX_VCPUS);42 /*43 * Number of file descriptors reqired, KVM_CAP_MAX_VCPUS for vCPU fds +44 * an arbitrary number for everything else.45 */46 int nr_fds_wanted = kvm_max_vcpus + 100;47 struct rlimit rl;48 49 pr_info("KVM_CAP_MAX_VCPU_ID: %d\n", kvm_max_vcpu_id);50 pr_info("KVM_CAP_MAX_VCPUS: %d\n", kvm_max_vcpus);51 52 /*53 * Check that we're allowed to open nr_fds_wanted file descriptors and54 * try raising the limits if needed.55 */56 TEST_ASSERT(!getrlimit(RLIMIT_NOFILE, &rl), "getrlimit() failed!");57 58 if (rl.rlim_cur < nr_fds_wanted) {59 rl.rlim_cur = nr_fds_wanted;60 if (rl.rlim_max < nr_fds_wanted) {61 int old_rlim_max = rl.rlim_max;62 rl.rlim_max = nr_fds_wanted;63 64 int r = setrlimit(RLIMIT_NOFILE, &rl);65 __TEST_REQUIRE(r >= 0,66 "RLIMIT_NOFILE hard limit is too low (%d, wanted %d)",67 old_rlim_max, nr_fds_wanted);68 } else {69 TEST_ASSERT(!setrlimit(RLIMIT_NOFILE, &rl), "setrlimit() failed!");70 }71 }72 73 /*74 * Upstream KVM prior to 4.8 does not support KVM_CAP_MAX_VCPU_ID.75 * Userspace is supposed to use KVM_CAP_MAX_VCPUS as the maximum ID76 * in this case.77 */78 if (!kvm_max_vcpu_id)79 kvm_max_vcpu_id = kvm_max_vcpus;80 81 TEST_ASSERT(kvm_max_vcpu_id >= kvm_max_vcpus,82 "KVM_MAX_VCPU_IDS (%d) must be at least as large as KVM_MAX_VCPUS (%d).",83 kvm_max_vcpu_id, kvm_max_vcpus);84 85 test_vcpu_creation(0, kvm_max_vcpus);86 87 if (kvm_max_vcpu_id > kvm_max_vcpus)88 test_vcpu_creation(89 kvm_max_vcpu_id - kvm_max_vcpus, kvm_max_vcpus);90 91 return 0;92}93