1 files changed, 35 insertions, 7 deletions

diff --git a/tools/testing/selftests/kvm/kvm_create_max_vcpus.c b/tools/testing/selftests/kvm/kvm_create_max_vcpus.c
index 6f38c3dc0d56..31b3cb24b9a7 100644
--- a/tools/testing/selftests/kvm/kvm_create_max_vcpus.c
+++ b/tools/testing/selftests/kvm/kvm_create_max_vcpus.c
@@ -12,6 +12,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/resource.h>
 
 #include "test_util.h"
 
@@ -24,14 +25,14 @@ void test_vcpu_creation(int first_vcpu_id, int num_vcpus)
 	struct kvm_vm *vm;
 	int i;
 
-	printf("Testing creating %d vCPUs, with IDs %d...%d.\n",
-	       num_vcpus, first_vcpu_id, first_vcpu_id + num_vcpus - 1);
+	pr_info("Testing creating %d vCPUs, with IDs %d...%d.\n",
+		num_vcpus, first_vcpu_id, first_vcpu_id + num_vcpus - 1);
 
-	vm = vm_create(VM_MODE_DEFAULT, DEFAULT_GUEST_PHY_PAGES, O_RDWR);
+	vm = vm_create_barebones();
 
 	for (i = first_vcpu_id; i < first_vcpu_id + num_vcpus; i++)
 		/* This asserts that the vCPU was created. */
-		vm_vcpu_add(vm, i);
+		__vm_vcpu_add(vm, i);
 
 	kvm_vm_free(vm);
 }
@@ -40,9 +41,36 @@ int main(int argc, char *argv[])
 {
 	int kvm_max_vcpu_id = kvm_check_cap(KVM_CAP_MAX_VCPU_ID);
 	int kvm_max_vcpus = kvm_check_cap(KVM_CAP_MAX_VCPUS);
+	/*
+	 * Number of file descriptors reqired, KVM_CAP_MAX_VCPUS for vCPU fds +
+	 * an arbitrary number for everything else.
+	 */
+	int nr_fds_wanted = kvm_max_vcpus + 100;
+	struct rlimit rl;
+
+	pr_info("KVM_CAP_MAX_VCPU_ID: %d\n", kvm_max_vcpu_id);
+	pr_info("KVM_CAP_MAX_VCPUS: %d\n", kvm_max_vcpus);
+
+	/*
+	 * Check that we're allowed to open nr_fds_wanted file descriptors and
+	 * try raising the limits if needed.
+	 */
+	TEST_ASSERT(!getrlimit(RLIMIT_NOFILE, &rl), "getrlimit() failed!");
+
+	if (rl.rlim_cur < nr_fds_wanted) {
+		rl.rlim_cur = nr_fds_wanted;
+		if (rl.rlim_max < nr_fds_wanted) {
+			int old_rlim_max = rl.rlim_max;
+			rl.rlim_max = nr_fds_wanted;
 
-	printf("KVM_CAP_MAX_VCPU_ID: %d\n", kvm_max_vcpu_id);
-	printf("KVM_CAP_MAX_VCPUS: %d\n", kvm_max_vcpus);
+			int r = setrlimit(RLIMIT_NOFILE, &rl);
+			__TEST_REQUIRE(r >= 0,
+				       "RLIMIT_NOFILE hard limit is too low (%d, wanted %d)\n",
+				       old_rlim_max, nr_fds_wanted);
+		} else {
+			TEST_ASSERT(!setrlimit(RLIMIT_NOFILE, &rl), "setrlimit() failed!");
+		}
+	}
 
 	/*
 	 * Upstream KVM prior to 4.8 does not support KVM_CAP_MAX_VCPU_ID.
@@ -53,7 +81,7 @@ int main(int argc, char *argv[])
 		kvm_max_vcpu_id = kvm_max_vcpus;
 
 	TEST_ASSERT(kvm_max_vcpu_id >= kvm_max_vcpus,
-		    "KVM_MAX_VCPU_ID (%d) must be at least as large as KVM_MAX_VCPUS (%d).",
+		    "KVM_MAX_VCPU_IDS (%d) must be at least as large as KVM_MAX_VCPUS (%d).",
 		    kvm_max_vcpu_id, kvm_max_vcpus);
 
 	test_vcpu_creation(0, kvm_max_vcpus);