Contributors: 3
Author Tokens Token Proportion Commits Commit Proportion
Nico Boehr 2308 98.55% 1 33.33%
Thomas Huth 31 1.32% 1 33.33%
Paolo Bonzini 3 0.13% 1 33.33%
Total 2342 3 


// SPDX-License-Identifier: GPL-2.0-only
/*
 * Test for s390x CMMA migration
 *
 * Copyright IBM Corp. 2023
 *
 * Authors:
 *  Nico Boehr <nrb@linux.ibm.com>
 */

#define _GNU_SOURCE /* for program_invocation_short_name */
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>

#include "test_util.h"
#include "kvm_util.h"
#include "kselftest.h"

#define MAIN_PAGE_COUNT 512

#define TEST_DATA_PAGE_COUNT 512
#define TEST_DATA_MEMSLOT 1
#define TEST_DATA_START_GFN 4096

#define TEST_DATA_TWO_PAGE_COUNT 256
#define TEST_DATA_TWO_MEMSLOT 2
#define TEST_DATA_TWO_START_GFN 8192

static char cmma_value_buf[MAIN_PAGE_COUNT + TEST_DATA_PAGE_COUNT];

/**
 * Dirty CMMA attributes of exactly one page in the TEST_DATA memslot,
 * so use_cmma goes on and the CMMA related ioctls do something.
 */
static void guest_do_one_essa(void)
{
	asm volatile(
		/* load TEST_DATA_START_GFN into r1 */
		"	llilf 1,%[start_gfn]\n"
		/* calculate the address from the gfn */
		"	sllg 1,1,12(0)\n"
		/* set the first page in TEST_DATA memslot to STABLE */
		"	.insn rrf,0xb9ab0000,2,1,1,0\n"
		/* hypercall */
		"	diag 0,0,0x501\n"
		"0:	j 0b"
		:
		: [start_gfn] "L"(TEST_DATA_START_GFN)
		: "r1", "r2", "memory", "cc"
	);
}

/**
 * Touch CMMA attributes of all pages in TEST_DATA memslot. Set them to stable
 * state.
 */
static void guest_dirty_test_data(void)
{
	asm volatile(
		/* r1 = TEST_DATA_START_GFN */
		"	xgr 1,1\n"
		"	llilf 1,%[start_gfn]\n"
		/* r5 = TEST_DATA_PAGE_COUNT */
		"	lghi 5,%[page_count]\n"
		/* r5 += r1 */
		"2:	agfr 5,1\n"
		/* r2 = r1 << 12 */
		"1:	sllg 2,1,12(0)\n"
		/* essa(r4, r2, SET_STABLE) */
		"	.insn rrf,0xb9ab0000,4,2,1,0\n"
		/* i++ */
		"	agfi 1,1\n"
		/* if r1 < r5 goto 1 */
		"	cgrjl 1,5,1b\n"
		/* hypercall */
		"	diag 0,0,0x501\n"
		"0:	j 0b"
		:
		: [start_gfn] "L"(TEST_DATA_START_GFN),
		  [page_count] "L"(TEST_DATA_PAGE_COUNT)
		:
			/* the counter in our loop over the pages */
			"r1",
			/* the calculated page physical address */
			"r2",
			/* ESSA output register */
			"r4",
			/* last page */
			"r5",
			"cc", "memory"
	);
}

static void create_main_memslot(struct kvm_vm *vm)
{
	int i;

	vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 0, 0, MAIN_PAGE_COUNT, 0);
	/* set the array of memslots to zero like __vm_create does */
	for (i = 0; i < NR_MEM_REGIONS; i++)
		vm->memslots[i] = 0;
}

static void create_test_memslot(struct kvm_vm *vm)
{
	vm_userspace_mem_region_add(vm,
				    VM_MEM_SRC_ANONYMOUS,
				    TEST_DATA_START_GFN << vm->page_shift,
				    TEST_DATA_MEMSLOT,
				    TEST_DATA_PAGE_COUNT,
				    0
				   );
	vm->memslots[MEM_REGION_TEST_DATA] = TEST_DATA_MEMSLOT;
}

static void create_memslots(struct kvm_vm *vm)
{
	/*
	 * Our VM has the following memory layout:
	 * +------+---------------------------+
	 * | GFN  | Memslot                   |
	 * +------+---------------------------+
	 * | 0    |                           |
	 * | ...  | MAIN (Code, Stack, ...)   |
	 * | 511  |                           |
	 * +------+---------------------------+
	 * | 4096 |                           |
	 * | ...  | TEST_DATA                 |
	 * | 4607 |                           |
	 * +------+---------------------------+
	 */
	create_main_memslot(vm);
	create_test_memslot(vm);
}

static void finish_vm_setup(struct kvm_vm *vm)
{
	struct userspace_mem_region *slot0;

	kvm_vm_elf_load(vm, program_invocation_name);

	slot0 = memslot2region(vm, 0);
	ucall_init(vm, slot0->region.guest_phys_addr + slot0->region.memory_size);

	kvm_arch_vm_post_create(vm);
}

static struct kvm_vm *create_vm_two_memslots(void)
{
	struct kvm_vm *vm;

	vm = vm_create_barebones();

	create_memslots(vm);

	finish_vm_setup(vm);

	return vm;
}

static void enable_cmma(struct kvm_vm *vm)
{
	int r;

	r = __kvm_device_attr_set(vm->fd, KVM_S390_VM_MEM_CTRL, KVM_S390_VM_MEM_ENABLE_CMMA, NULL);
	TEST_ASSERT(!r, "enabling cmma failed r=%d errno=%d", r, errno);
}

static void enable_dirty_tracking(struct kvm_vm *vm)
{
	vm_mem_region_set_flags(vm, 0, KVM_MEM_LOG_DIRTY_PAGES);
	vm_mem_region_set_flags(vm, TEST_DATA_MEMSLOT, KVM_MEM_LOG_DIRTY_PAGES);
}

static int __enable_migration_mode(struct kvm_vm *vm)
{
	return __kvm_device_attr_set(vm->fd,
				     KVM_S390_VM_MIGRATION,
				     KVM_S390_VM_MIGRATION_START,
				     NULL
				    );
}

static void enable_migration_mode(struct kvm_vm *vm)
{
	int r = __enable_migration_mode(vm);

	TEST_ASSERT(!r, "enabling migration mode failed r=%d errno=%d", r, errno);
}

static bool is_migration_mode_on(struct kvm_vm *vm)
{
	u64 out;
	int r;

	r = __kvm_device_attr_get(vm->fd,
				  KVM_S390_VM_MIGRATION,
				  KVM_S390_VM_MIGRATION_STATUS,
				  &out
				 );
	TEST_ASSERT(!r, "getting migration mode status failed r=%d errno=%d", r, errno);
	return out;
}

static int vm_get_cmma_bits(struct kvm_vm *vm, u64 flags, int *errno_out)
{
	struct kvm_s390_cmma_log args;
	int rc;

	errno = 0;

	args = (struct kvm_s390_cmma_log){
		.start_gfn = 0,
		.count = sizeof(cmma_value_buf),
		.flags = flags,
		.values = (__u64)&cmma_value_buf[0]
	};
	rc = __vm_ioctl(vm, KVM_S390_GET_CMMA_BITS, &args);

	*errno_out = errno;
	return rc;
}

static void test_get_cmma_basic(void)
{
	struct kvm_vm *vm = create_vm_two_memslots();
	struct kvm_vcpu *vcpu;
	int rc, errno_out;

	/* GET_CMMA_BITS without CMMA enabled should fail */
	rc = vm_get_cmma_bits(vm, 0, &errno_out);
	TEST_ASSERT_EQ(rc, -1);
	TEST_ASSERT_EQ(errno_out, ENXIO);

	enable_cmma(vm);
	vcpu = vm_vcpu_add(vm, 1, guest_do_one_essa);

	vcpu_run(vcpu);

	/* GET_CMMA_BITS without migration mode and without peeking should fail */
	rc = vm_get_cmma_bits(vm, 0, &errno_out);
	TEST_ASSERT_EQ(rc, -1);
	TEST_ASSERT_EQ(errno_out, EINVAL);

	/* GET_CMMA_BITS without migration mode and with peeking should work */
	rc = vm_get_cmma_bits(vm, KVM_S390_CMMA_PEEK, &errno_out);
	TEST_ASSERT_EQ(rc, 0);
	TEST_ASSERT_EQ(errno_out, 0);

	enable_dirty_tracking(vm);
	enable_migration_mode(vm);

	/* GET_CMMA_BITS with invalid flags */
	rc = vm_get_cmma_bits(vm, 0xfeedc0fe, &errno_out);
	TEST_ASSERT_EQ(rc, -1);
	TEST_ASSERT_EQ(errno_out, EINVAL);

	kvm_vm_free(vm);
}

static void assert_exit_was_hypercall(struct kvm_vcpu *vcpu)
{
	TEST_ASSERT_EQ(vcpu->run->exit_reason, 13);
	TEST_ASSERT_EQ(vcpu->run->s390_sieic.icptcode, 4);
	TEST_ASSERT_EQ(vcpu->run->s390_sieic.ipa, 0x8300);
	TEST_ASSERT_EQ(vcpu->run->s390_sieic.ipb, 0x5010000);
}

static void test_migration_mode(void)
{
	struct kvm_vm *vm = vm_create_barebones();
	struct kvm_vcpu *vcpu;
	u64 orig_psw;
	int rc;

	/* enabling migration mode on a VM without memory should fail */
	rc = __enable_migration_mode(vm);
	TEST_ASSERT_EQ(rc, -1);
	TEST_ASSERT_EQ(errno, EINVAL);
	TEST_ASSERT(!is_migration_mode_on(vm), "migration mode should still be off");
	errno = 0;

	create_memslots(vm);
	finish_vm_setup(vm);

	enable_cmma(vm);
	vcpu = vm_vcpu_add(vm, 1, guest_do_one_essa);
	orig_psw = vcpu->run->psw_addr;

	/*
	 * Execute one essa instruction in the guest. Otherwise the guest will
	 * not have use_cmm enabled and GET_CMMA_BITS will return no pages.
	 */
	vcpu_run(vcpu);
	assert_exit_was_hypercall(vcpu);

	/* migration mode when memslots have dirty tracking off should fail */
	rc = __enable_migration_mode(vm);
	TEST_ASSERT_EQ(rc, -1);
	TEST_ASSERT_EQ(errno, EINVAL);
	TEST_ASSERT(!is_migration_mode_on(vm), "migration mode should still be off");
	errno = 0;

	/* enable dirty tracking */
	enable_dirty_tracking(vm);

	/* enabling migration mode should work now */
	rc = __enable_migration_mode(vm);
	TEST_ASSERT_EQ(rc, 0);
	TEST_ASSERT(is_migration_mode_on(vm), "migration mode should be on");
	errno = 0;

	/* execute another ESSA instruction to see this goes fine */
	vcpu->run->psw_addr = orig_psw;
	vcpu_run(vcpu);
	assert_exit_was_hypercall(vcpu);

	/*
	 * With migration mode on, create a new memslot with dirty tracking off.
	 * This should turn off migration mode.
	 */
	TEST_ASSERT(is_migration_mode_on(vm), "migration mode should be on");
	vm_userspace_mem_region_add(vm,
				    VM_MEM_SRC_ANONYMOUS,
				    TEST_DATA_TWO_START_GFN << vm->page_shift,
				    TEST_DATA_TWO_MEMSLOT,
				    TEST_DATA_TWO_PAGE_COUNT,
				    0
				   );
	TEST_ASSERT(!is_migration_mode_on(vm),
		    "creating memslot without dirty tracking turns off migration mode"
		   );

	/* ESSA instructions should still execute fine */
	vcpu->run->psw_addr = orig_psw;
	vcpu_run(vcpu);
	assert_exit_was_hypercall(vcpu);

	/*
	 * Turn on dirty tracking on the new memslot.
	 * It should be possible to turn migration mode back on again.
	 */
	vm_mem_region_set_flags(vm, TEST_DATA_TWO_MEMSLOT, KVM_MEM_LOG_DIRTY_PAGES);
	rc = __enable_migration_mode(vm);
	TEST_ASSERT_EQ(rc, 0);
	TEST_ASSERT(is_migration_mode_on(vm), "migration mode should be on");
	errno = 0;

	/*
	 * Turn off dirty tracking again, this time with just a flag change.
	 * Again, migration mode should turn off.
	 */
	TEST_ASSERT(is_migration_mode_on(vm), "migration mode should be on");
	vm_mem_region_set_flags(vm, TEST_DATA_TWO_MEMSLOT, 0);
	TEST_ASSERT(!is_migration_mode_on(vm),
		    "disabling dirty tracking should turn off migration mode"
		   );

	/* ESSA instructions should still execute fine */
	vcpu->run->psw_addr = orig_psw;
	vcpu_run(vcpu);
	assert_exit_was_hypercall(vcpu);

	kvm_vm_free(vm);
}

/**
 * Given a VM with the MAIN and TEST_DATA memslot, assert that both slots have
 * CMMA attributes of all pages in both memslots and nothing more dirty.
 * This has the useful side effect of ensuring nothing is CMMA dirty after this
 * function.
 */
static void assert_all_slots_cmma_dirty(struct kvm_vm *vm)
{
	struct kvm_s390_cmma_log args;

	/*
	 * First iteration - everything should be dirty.
	 * Start at the main memslot...
	 */
	args = (struct kvm_s390_cmma_log){
		.start_gfn = 0,
		.count = sizeof(cmma_value_buf),
		.flags = 0,
		.values = (__u64)&cmma_value_buf[0]
	};
	memset(cmma_value_buf, 0xff, sizeof(cmma_value_buf));
	vm_ioctl(vm, KVM_S390_GET_CMMA_BITS, &args);
	TEST_ASSERT_EQ(args.count, MAIN_PAGE_COUNT);
	TEST_ASSERT_EQ(args.remaining, TEST_DATA_PAGE_COUNT);
	TEST_ASSERT_EQ(args.start_gfn, 0);

	/* ...and then - after a hole - the TEST_DATA memslot should follow */
	args = (struct kvm_s390_cmma_log){
		.start_gfn = MAIN_PAGE_COUNT,
		.count = sizeof(cmma_value_buf),
		.flags = 0,
		.values = (__u64)&cmma_value_buf[0]
	};
	memset(cmma_value_buf, 0xff, sizeof(cmma_value_buf));
	vm_ioctl(vm, KVM_S390_GET_CMMA_BITS, &args);
	TEST_ASSERT_EQ(args.count, TEST_DATA_PAGE_COUNT);
	TEST_ASSERT_EQ(args.start_gfn, TEST_DATA_START_GFN);
	TEST_ASSERT_EQ(args.remaining, 0);

	/* ...and nothing else should be there */
	args = (struct kvm_s390_cmma_log){
		.start_gfn = TEST_DATA_START_GFN + TEST_DATA_PAGE_COUNT,
		.count = sizeof(cmma_value_buf),
		.flags = 0,
		.values = (__u64)&cmma_value_buf[0]
	};
	memset(cmma_value_buf, 0xff, sizeof(cmma_value_buf));
	vm_ioctl(vm, KVM_S390_GET_CMMA_BITS, &args);
	TEST_ASSERT_EQ(args.count, 0);
	TEST_ASSERT_EQ(args.start_gfn, 0);
	TEST_ASSERT_EQ(args.remaining, 0);
}

/**
 * Given a VM, assert no pages are CMMA dirty.
 */
static void assert_no_pages_cmma_dirty(struct kvm_vm *vm)
{
	struct kvm_s390_cmma_log args;

	/* If we start from GFN 0 again, nothing should be dirty. */
	args = (struct kvm_s390_cmma_log){
		.start_gfn = 0,
		.count = sizeof(cmma_value_buf),
		.flags = 0,
		.values = (__u64)&cmma_value_buf[0]
	};
	memset(cmma_value_buf, 0xff, sizeof(cmma_value_buf));
	vm_ioctl(vm, KVM_S390_GET_CMMA_BITS, &args);
	if (args.count || args.remaining || args.start_gfn)
		TEST_FAIL("pages are still dirty start_gfn=0x%llx count=%u remaining=%llu",
			  args.start_gfn,
			  args.count,
			  args.remaining
			 );
}

static void test_get_inital_dirty(void)
{
	struct kvm_vm *vm = create_vm_two_memslots();
	struct kvm_vcpu *vcpu;

	enable_cmma(vm);
	vcpu = vm_vcpu_add(vm, 1, guest_do_one_essa);

	/*
	 * Execute one essa instruction in the guest. Otherwise the guest will
	 * not have use_cmm enabled and GET_CMMA_BITS will return no pages.
	 */
	vcpu_run(vcpu);
	assert_exit_was_hypercall(vcpu);

	enable_dirty_tracking(vm);
	enable_migration_mode(vm);

	assert_all_slots_cmma_dirty(vm);

	/* Start from the beginning again and make sure nothing else is dirty */
	assert_no_pages_cmma_dirty(vm);

	kvm_vm_free(vm);
}

static void query_cmma_range(struct kvm_vm *vm,
			     u64 start_gfn, u64 gfn_count,
			     struct kvm_s390_cmma_log *res_out)
{
	*res_out = (struct kvm_s390_cmma_log){
		.start_gfn = start_gfn,
		.count = gfn_count,
		.flags = 0,
		.values = (__u64)&cmma_value_buf[0]
	};
	memset(cmma_value_buf, 0xff, sizeof(cmma_value_buf));
	vm_ioctl(vm, KVM_S390_GET_CMMA_BITS, res_out);
}

/**
 * Assert the given cmma_log struct that was executed by query_cmma_range()
 * indicates the first dirty gfn is at first_dirty_gfn and contains exactly
 * dirty_gfn_count CMMA values.
 */
static void assert_cmma_dirty(u64 first_dirty_gfn,
			      u64 dirty_gfn_count,
			      const struct kvm_s390_cmma_log *res)
{
	TEST_ASSERT_EQ(res->start_gfn, first_dirty_gfn);
	TEST_ASSERT_EQ(res->count, dirty_gfn_count);
	for (size_t i = 0; i < dirty_gfn_count; i++)
		TEST_ASSERT_EQ(cmma_value_buf[0], 0x0); /* stable state */
	TEST_ASSERT_EQ(cmma_value_buf[dirty_gfn_count], 0xff); /* not touched */
}

static void test_get_skip_holes(void)
{
	size_t gfn_offset;
	struct kvm_vm *vm = create_vm_two_memslots();
	struct kvm_s390_cmma_log log;
	struct kvm_vcpu *vcpu;
	u64 orig_psw;

	enable_cmma(vm);
	vcpu = vm_vcpu_add(vm, 1, guest_dirty_test_data);

	orig_psw = vcpu->run->psw_addr;

	/*
	 * Execute some essa instructions in the guest. Otherwise the guest will
	 * not have use_cmm enabled and GET_CMMA_BITS will return no pages.
	 */
	vcpu_run(vcpu);
	assert_exit_was_hypercall(vcpu);

	enable_dirty_tracking(vm);
	enable_migration_mode(vm);

	/* un-dirty all pages */
	assert_all_slots_cmma_dirty(vm);

	/* Then, dirty just the TEST_DATA memslot */
	vcpu->run->psw_addr = orig_psw;
	vcpu_run(vcpu);

	gfn_offset = TEST_DATA_START_GFN;
	/**
	 * Query CMMA attributes of one page, starting at page 0. Since the
	 * main memslot was not touched by the VM, this should yield the first
	 * page of the TEST_DATA memslot.
	 * The dirty bitmap should now look like this:
	 * 0: not dirty
	 * [0x1, 0x200): dirty
	 */
	query_cmma_range(vm, 0, 1, &log);
	assert_cmma_dirty(gfn_offset, 1, &log);
	gfn_offset++;

	/**
	 * Query CMMA attributes of 32 (0x20) pages past the end of the TEST_DATA
	 * memslot. This should wrap back to the beginning of the TEST_DATA
	 * memslot, page 1.
	 * The dirty bitmap should now look like this:
	 * [0, 0x21): not dirty
	 * [0x21, 0x200): dirty
	 */
	query_cmma_range(vm, TEST_DATA_START_GFN + TEST_DATA_PAGE_COUNT, 0x20, &log);
	assert_cmma_dirty(gfn_offset, 0x20, &log);
	gfn_offset += 0x20;

	/* Skip 32 pages */
	gfn_offset += 0x20;

	/**
	 * After skipping 32 pages, query the next 32 (0x20) pages.
	 * The dirty bitmap should now look like this:
	 * [0, 0x21): not dirty
	 * [0x21, 0x41): dirty
	 * [0x41, 0x61): not dirty
	 * [0x61, 0x200): dirty
	 */
	query_cmma_range(vm, gfn_offset, 0x20, &log);
	assert_cmma_dirty(gfn_offset, 0x20, &log);
	gfn_offset += 0x20;

	/**
	 * Query 1 page from the beginning of the TEST_DATA memslot. This should
	 * yield page 0x21.
	 * The dirty bitmap should now look like this:
	 * [0, 0x22): not dirty
	 * [0x22, 0x41): dirty
	 * [0x41, 0x61): not dirty
	 * [0x61, 0x200): dirty
	 */
	query_cmma_range(vm, TEST_DATA_START_GFN, 1, &log);
	assert_cmma_dirty(TEST_DATA_START_GFN + 0x21, 1, &log);
	gfn_offset++;

	/**
	 * Query 15 (0xF) pages from page 0x23 in TEST_DATA memslot.
	 * This should yield pages [0x23, 0x33).
	 * The dirty bitmap should now look like this:
	 * [0, 0x22): not dirty
	 * 0x22: dirty
	 * [0x23, 0x33): not dirty
	 * [0x33, 0x41): dirty
	 * [0x41, 0x61): not dirty
	 * [0x61, 0x200): dirty
	 */
	gfn_offset = TEST_DATA_START_GFN + 0x23;
	query_cmma_range(vm, gfn_offset, 15, &log);
	assert_cmma_dirty(gfn_offset, 15, &log);

	/**
	 * Query 17 (0x11) pages from page 0x22 in TEST_DATA memslot.
	 * This should yield page [0x22, 0x33)
	 * The dirty bitmap should now look like this:
	 * [0, 0x33): not dirty
	 * [0x33, 0x41): dirty
	 * [0x41, 0x61): not dirty
	 * [0x61, 0x200): dirty
	 */
	gfn_offset = TEST_DATA_START_GFN + 0x22;
	query_cmma_range(vm, gfn_offset, 17, &log);
	assert_cmma_dirty(gfn_offset, 17, &log);

	/**
	 * Query 25 (0x19) pages from page 0x40 in TEST_DATA memslot.
	 * This should yield page 0x40 and nothing more, since there are more
	 * than 16 non-dirty pages after page 0x40.
	 * The dirty bitmap should now look like this:
	 * [0, 0x33): not dirty
	 * [0x33, 0x40): dirty
	 * [0x40, 0x61): not dirty
	 * [0x61, 0x200): dirty
	 */
	gfn_offset = TEST_DATA_START_GFN + 0x40;
	query_cmma_range(vm, gfn_offset, 25, &log);
	assert_cmma_dirty(gfn_offset, 1, &log);

	/**
	 * Query pages [0x33, 0x40).
	 * The dirty bitmap should now look like this:
	 * [0, 0x61): not dirty
	 * [0x61, 0x200): dirty
	 */
	gfn_offset = TEST_DATA_START_GFN + 0x33;
	query_cmma_range(vm, gfn_offset, 0x40 - 0x33, &log);
	assert_cmma_dirty(gfn_offset, 0x40 - 0x33, &log);

	/**
	 * Query the remaining pages [0x61, 0x200).
	 */
	gfn_offset = TEST_DATA_START_GFN;
	query_cmma_range(vm, gfn_offset, TEST_DATA_PAGE_COUNT - 0x61, &log);
	assert_cmma_dirty(TEST_DATA_START_GFN + 0x61, TEST_DATA_PAGE_COUNT - 0x61, &log);

	assert_no_pages_cmma_dirty(vm);
}

struct testdef {
	const char *name;
	void (*test)(void);
} testlist[] = {
	{ "migration mode and dirty tracking", test_migration_mode },
	{ "GET_CMMA_BITS: basic calls", test_get_cmma_basic },
	{ "GET_CMMA_BITS: all pages are dirty initally", test_get_inital_dirty },
	{ "GET_CMMA_BITS: holes are skipped", test_get_skip_holes },
};

/**
 * The kernel may support CMMA, but the machine may not (i.e. if running as
 * guest-3).
 *
 * In this case, the CMMA capabilities are all there, but the CMMA-related
 * ioctls fail. To find out whether the machine supports CMMA, create a
 * temporary VM and then query the CMMA feature of the VM.
 */
static int machine_has_cmma(void)
{
	struct kvm_vm *vm = vm_create_barebones();
	int r;

	r = !__kvm_has_device_attr(vm->fd, KVM_S390_VM_MEM_CTRL, KVM_S390_VM_MEM_ENABLE_CMMA);
	kvm_vm_free(vm);

	return r;
}

int main(int argc, char *argv[])
{
	int idx;

	TEST_REQUIRE(kvm_has_cap(KVM_CAP_SYNC_REGS));
	TEST_REQUIRE(kvm_has_cap(KVM_CAP_S390_CMMA_MIGRATION));
	TEST_REQUIRE(machine_has_cmma());

	ksft_print_header();

	ksft_set_plan(ARRAY_SIZE(testlist));

	for (idx = 0; idx < ARRAY_SIZE(testlist); idx++) {
		testlist[idx].test();
		ksft_test_result_pass("%s\n", testlist[idx].name);
	}

	ksft_finished();	/* Print results and exit() accordingly */
}