@@ -103,6 +103,7 @@ TEST_GEN_PROGS_x86_64 += system_counter_offset_test
TEST_GEN_PROGS_aarch64 += aarch64/arch_timer
TEST_GEN_PROGS_aarch64 += aarch64/debug-exceptions
TEST_GEN_PROGS_aarch64 += aarch64/get-reg-list
+TEST_GEN_PROGS_aarch64 += aarch64/page_fault_test
TEST_GEN_PROGS_aarch64 += aarch64/psci_cpu_on_test
TEST_GEN_PROGS_aarch64 += aarch64/vgic_init
TEST_GEN_PROGS_aarch64 += aarch64/vgic_irq
new file mode 100644
@@ -0,0 +1,667 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * page_fault_test.c - Test stage 2 faults.
+ *
+ * This test tries different combinations of guest accesses (e.g., write,
+ * S1PTW), backing source type (e.g., anon) and types of faults (e.g., read on
+ * hugetlbfs with a hole). It checks that the expected handling method is
+ * called (e.g., uffd faults with the right address and write/read flag).
+ */
+
+#define _GNU_SOURCE
+#include <linux/bitmap.h>
+#include <fcntl.h>
+#include <test_util.h>
+#include <kvm_util.h>
+#include <processor.h>
+#include "guest_modes.h"
+#include "userfaultfd_util.h"
+
+#define VCPU_ID 0
+
+#define TEST_MEM_SLOT_INDEX 1
+#define TEST_PT_SLOT_INDEX 2
+
+/* Max number of backing pages per guest page */
+#define BACKING_PG_PER_GUEST_PG (64 / 4)
+
+/* Test memslot in backing source pages */
+#define TEST_MEMSLOT_BACKING_SRC_NPAGES (1 * BACKING_PG_PER_GUEST_PG)
+
+/* PT memslot size in backing source pages */
+#define PT_MEMSLOT_BACKING_SRC_NPAGES (4 * BACKING_PG_PER_GUEST_PG)
+
+/* Guest virtual addresses that point to the test page and its PTE. */
+#define GUEST_TEST_GVA 0xc0000000
+#define GUEST_TEST_EXEC_GVA 0xc0000008
+#define GUEST_TEST_PTE_GVA 0xd0000000
+
+/* Access flag */
+#define PTE_AF (1ULL << 10)
+
+/* Acces flag update enable/disable */
+#define TCR_EL1_HA (1ULL << 39)
+
+#define CMD_SKIP_TEST (-1LL)
+#define CMD_HOLE_PT (1ULL << 2)
+#define CMD_HOLE_TEST (1ULL << 3)
+
+#define PREPARE_FN_NR 10
+#define CHECK_FN_NR 10
+
+static const uint64_t test_gva = GUEST_TEST_GVA;
+static const uint64_t test_exec_gva = GUEST_TEST_EXEC_GVA;
+static const uint64_t pte_gva = GUEST_TEST_PTE_GVA;
+uint64_t pte_gpa;
+
+enum { PT, TEST, NR_MEMSLOTS};
+
+struct memslot_desc {
+ void *hva;
+ uint64_t gpa;
+ uint64_t size;
+ uint64_t guest_pages;
+ uint64_t backing_pages;
+ enum vm_mem_backing_src_type src_type;
+ uint32_t idx;
+} memslot[NR_MEMSLOTS] = {
+ {
+ .idx = TEST_PT_SLOT_INDEX,
+ .backing_pages = PT_MEMSLOT_BACKING_SRC_NPAGES,
+ },
+ {
+ .idx = TEST_MEM_SLOT_INDEX,
+ .backing_pages = TEST_MEMSLOT_BACKING_SRC_NPAGES,
+ },
+};
+
+static struct event_cnt {
+ int aborts;
+ int fail_vcpu_runs;
+} events;
+
+struct test_desc {
+ const char *name;
+ uint64_t mem_mark_cmd;
+ /* Skip the test if any prepare function returns false */
+ bool (*guest_prepare[PREPARE_FN_NR])(void);
+ void (*guest_test)(void);
+ void (*guest_test_check[CHECK_FN_NR])(void);
+ void (*dabt_handler)(struct ex_regs *regs);
+ void (*iabt_handler)(struct ex_regs *regs);
+ uint32_t pt_memslot_flags;
+ uint32_t test_memslot_flags;
+ void (*guest_pre_run)(struct kvm_vm *vm);
+ bool skip;
+ struct event_cnt expected_events;
+};
+
+struct test_params {
+ enum vm_mem_backing_src_type src_type;
+ struct test_desc *test_desc;
+};
+
+
+static inline void flush_tlb_page(uint64_t vaddr)
+{
+ uint64_t page = vaddr >> 12;
+
+ dsb(ishst);
+ asm("tlbi vaae1is, %0" :: "r" (page));
+ dsb(ish);
+ isb();
+}
+
+#define RET 0xd65f03c0
+#define MOV_X0(x) (0xd2800000 | (((x) & 0xffff) << 5))
+
+static void guest_test_nop(void)
+{}
+
+static void guest_test_write64(void)
+{
+ uint64_t val;
+
+ WRITE_ONCE(*((uint64_t *)test_gva), 0x0123456789ABCDEF);
+ val = READ_ONCE(*(uint64_t *)test_gva);
+ GUEST_ASSERT_EQ(val, 0x0123456789ABCDEF);
+}
+
+/* Check the system for atomic instructions. */
+static bool guest_check_lse(void)
+{
+ uint64_t isar0 = read_sysreg(id_aa64isar0_el1);
+ uint64_t atomic = (isar0 >> 20) & 7;
+
+ return atomic >= 2;
+}
+
+/* Compare and swap instruction. */
+static void guest_test_cas(void)
+{
+ uint64_t val;
+ uint64_t addr = test_gva;
+
+ GUEST_ASSERT_EQ(guest_check_lse(), 1);
+ asm volatile(".arch_extension lse\n"
+ "casal %0, %1, [%2]\n"
+ :: "r" (0), "r" (0x0123456789ABCDEF), "r" (addr));
+ val = READ_ONCE(*(uint64_t *)(addr));
+ GUEST_ASSERT_EQ(val, 0x0123456789ABCDEF);
+}
+
+static void guest_test_read64(void)
+{
+ uint64_t val;
+
+ val = READ_ONCE(*(uint64_t *)test_gva);
+ GUEST_ASSERT_EQ(val, 0);
+}
+
+/* Address translation instruction */
+static void guest_test_at(void)
+{
+ uint64_t par;
+ uint64_t addr = 0;
+
+ asm volatile("at s1e1r, %0" :: "r" (test_gva));
+ par = read_sysreg(par_el1);
+
+ /* Bit 1 indicates whether the AT was successful */
+ GUEST_ASSERT_EQ(par & 1, 0);
+ /* The PA in bits [51:12] */
+ addr = par & (((1ULL << 40) - 1) << 12);
+ GUEST_ASSERT_EQ(addr, memslot[TEST].gpa);
+}
+
+static void guest_test_dc_zva(void)
+{
+ /* The smallest guaranteed block size (bs) is a word. */
+ uint16_t val;
+
+ asm volatile("dc zva, %0\n"
+ "dsb ish\n"
+ :: "r" (test_gva));
+ val = READ_ONCE(*(uint16_t *)test_gva);
+ GUEST_ASSERT_EQ(val, 0);
+}
+
+static void guest_test_ld_preidx(void)
+{
+ uint64_t val;
+ uint64_t addr = test_gva - 8;
+
+ /*
+ * This ends up accessing "test_gva + 8 - 8", where "test_gva - 8"
+ * is not backed by a memslot.
+ */
+ asm volatile("ldr %0, [%1, #8]!"
+ : "=r" (val), "+r" (addr));
+ GUEST_ASSERT_EQ(val, 0);
+ GUEST_ASSERT_EQ(addr, test_gva);
+}
+
+static void guest_test_st_preidx(void)
+{
+ uint64_t val = 0x0123456789ABCDEF;
+ uint64_t addr = test_gva - 8;
+
+ asm volatile("str %0, [%1, #8]!"
+ : "+r" (val), "+r" (addr));
+
+ GUEST_ASSERT_EQ(addr, test_gva);
+ val = READ_ONCE(*(uint64_t *)test_gva);
+}
+
+static bool guest_set_ha(void)
+{
+ uint64_t mmfr1 = read_sysreg(id_aa64mmfr1_el1);
+ uint64_t hadbs = mmfr1 & 6;
+ uint64_t tcr;
+
+ /* Skip if HA is not supported. */
+ if (hadbs == 0)
+ return false;
+
+ tcr = read_sysreg(tcr_el1) | TCR_EL1_HA;
+ write_sysreg(tcr, tcr_el1);
+ isb();
+
+ return true;
+}
+
+static bool guest_clear_pte_af(void)
+{
+ *((uint64_t *)pte_gva) &= ~PTE_AF;
+ flush_tlb_page(pte_gva);
+
+ return true;
+}
+
+static void guest_check_pte_af(void)
+{
+ flush_tlb_page(pte_gva);
+ GUEST_ASSERT_EQ(*((uint64_t *)pte_gva) & PTE_AF, PTE_AF);
+}
+
+static void guest_test_exec(void)
+{
+ int (*code)(void) = (int (*)(void))test_exec_gva;
+ int ret;
+
+ ret = code();
+ GUEST_ASSERT_EQ(ret, 0x77);
+}
+
+static bool guest_prepare(struct test_desc *test)
+{
+ bool (*prepare_fn)(void);
+ int i;
+
+ for (i = 0; i < PREPARE_FN_NR; i++) {
+ prepare_fn = test->guest_prepare[i];
+ if (prepare_fn && !prepare_fn())
+ return false;
+ }
+
+ return true;
+}
+
+static void guest_test_check(struct test_desc *test)
+{
+ void (*check_fn)(void);
+ int i;
+
+ for (i = 0; i < CHECK_FN_NR; i++) {
+ check_fn = test->guest_test_check[i];
+ if (!check_fn)
+ continue;
+ check_fn();
+ }
+}
+
+static void guest_code(struct test_desc *test)
+{
+ if (!test->guest_test)
+ test->guest_test = guest_test_nop;
+
+ if (!guest_prepare(test))
+ GUEST_SYNC(CMD_SKIP_TEST);
+
+ GUEST_SYNC(test->mem_mark_cmd);
+ test->guest_test();
+
+ guest_test_check(test);
+ GUEST_DONE();
+}
+
+static void no_dabt_handler(struct ex_regs *regs)
+{
+ GUEST_ASSERT_1(false, read_sysreg(far_el1));
+}
+
+static void no_iabt_handler(struct ex_regs *regs)
+{
+ GUEST_ASSERT_1(false, regs->pc);
+}
+
+static void punch_hole_in_memslot(struct kvm_vm *vm,
+ struct memslot_desc *memslot)
+{
+ int ret, fd;
+ void *hva;
+
+ fd = vm_mem_region_get_src_fd(vm, memslot->idx);
+ if (fd != -1) {
+ ret = fallocate(fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
+ 0, memslot->size);
+ TEST_ASSERT(ret == 0, "fallocate failed, errno: %d\n", errno);
+ } else {
+ hva = addr_gpa2hva(vm, memslot->gpa);
+ ret = madvise(hva, memslot->size, MADV_DONTNEED);
+ TEST_ASSERT(ret == 0, "madvise failed, errno: %d\n", errno);
+ }
+}
+
+static void handle_cmd(struct kvm_vm *vm, int cmd)
+{
+ if (cmd & CMD_HOLE_PT)
+ punch_hole_in_memslot(vm, &memslot[PT]);
+ if (cmd & CMD_HOLE_TEST)
+ punch_hole_in_memslot(vm, &memslot[TEST]);
+}
+
+static void sync_stats_from_guest(struct kvm_vm *vm)
+{
+ struct event_cnt *ec = addr_gva2hva(vm, (uint64_t)&events);
+
+ events.aborts += ec->aborts;
+}
+
+void fail_vcpu_run_no_handler(int ret)
+{
+ TEST_FAIL("Unexpected vcpu run failure\n");
+}
+
+static uint64_t get_total_guest_pages(enum vm_guest_mode mode,
+ struct test_params *p)
+{
+ uint64_t large_page_size = get_backing_src_pagesz(p->src_type);
+ uint64_t guest_page_size = vm_guest_mode_params[mode].page_size;
+ uint64_t size;
+
+ size = PT_MEMSLOT_BACKING_SRC_NPAGES * large_page_size;
+ size += TEST_MEMSLOT_BACKING_SRC_NPAGES * large_page_size;
+
+ return size / guest_page_size;
+}
+
+static void load_exec_code_for_test(void)
+{
+ uint32_t *code;
+
+ /* Write this "code" into test_exec_gva */
+ assert(test_exec_gva - test_gva);
+ code = memslot[TEST].hva + 8;
+
+ code[0] = MOV_X0(0x77);
+ code[1] = RET;
+}
+
+static void setup_guest_args(struct kvm_vm *vm, struct test_desc *test)
+{
+ vm_vaddr_t test_desc_gva;
+
+ test_desc_gva = vm_vaddr_alloc_page(vm);
+ memcpy(addr_gva2hva(vm, test_desc_gva), test,
+ sizeof(struct test_desc));
+ vcpu_args_set(vm, 0, 1, test_desc_gva);
+}
+
+static void setup_abort_handlers(struct kvm_vm *vm, struct test_desc *test)
+{
+ vm_init_descriptor_tables(vm);
+ vcpu_init_descriptor_tables(vm, VCPU_ID);
+ if (!test->dabt_handler)
+ test->dabt_handler = no_dabt_handler;
+ if (!test->iabt_handler)
+ test->iabt_handler = no_iabt_handler;
+ vm_install_sync_handler(vm, VECTOR_SYNC_CURRENT,
+ 0x25, test->dabt_handler);
+ vm_install_sync_handler(vm, VECTOR_SYNC_CURRENT,
+ 0x21, test->iabt_handler);
+}
+
+static void setup_memslots(struct kvm_vm *vm, enum vm_guest_mode mode,
+ struct test_params *p)
+{
+ uint64_t large_page_size = get_backing_src_pagesz(p->src_type);
+ uint64_t guest_page_size = vm_guest_mode_params[mode].page_size;
+ struct test_desc *test = p->test_desc;
+ uint64_t hole_gpa;
+ uint64_t alignment;
+ int i;
+
+ /* Calculate the test and PT memslot sizes */
+ for (i = 0; i < NR_MEMSLOTS; i++) {
+ memslot[i].size = large_page_size * memslot[i].backing_pages;
+ memslot[i].guest_pages = memslot[i].size / guest_page_size;
+ memslot[i].src_type = p->src_type;
+ }
+
+ TEST_ASSERT(memslot[TEST].size >= guest_page_size,
+ "The test memslot should have space one guest page.\n");
+ TEST_ASSERT(memslot[PT].size >= (4 * guest_page_size),
+ "The PT memslot sould have space for 4 guest pages.\n");
+
+ /* Place the memslots GPAs at the end of physical memory */
+ alignment = max(large_page_size, guest_page_size);
+ memslot[TEST].gpa = (vm_get_max_gfn(vm) - memslot[TEST].guest_pages) *
+ guest_page_size;
+ memslot[TEST].gpa = align_down(memslot[TEST].gpa, alignment);
+ /* Add a 1-guest_page-hole between the two memslots */
+ hole_gpa = memslot[TEST].gpa - guest_page_size;
+ virt_pg_map(vm, test_gva - guest_page_size, hole_gpa);
+ memslot[PT].gpa = hole_gpa - (memslot[PT].guest_pages *
+ guest_page_size);
+ memslot[PT].gpa = align_down(memslot[PT].gpa, alignment);
+
+ /* Create memslots for and test data and a PTE. */
+ vm_userspace_mem_region_add(vm, p->src_type, memslot[PT].gpa,
+ memslot[PT].idx, memslot[PT].guest_pages,
+ test->pt_memslot_flags);
+ vm_userspace_mem_region_add(vm, p->src_type, memslot[TEST].gpa,
+ memslot[TEST].idx, memslot[TEST].guest_pages,
+ test->test_memslot_flags);
+
+ for (i = 0; i < NR_MEMSLOTS; i++)
+ memslot[i].hva = addr_gpa2hva(vm, memslot[i].gpa);
+
+ /* Map the test test_gva using the PT memslot. */
+ _virt_pg_map(vm, test_gva, memslot[TEST].gpa,
+ 4 /* NORMAL (See DEFAULT_MAIR_EL1) */,
+ TEST_PT_SLOT_INDEX);
+
+ /*
+ * Find the PTE of the test page and map it in the guest so it can
+ * clear the AF.
+ */
+ pte_gpa = vm_get_pte_gpa(vm, test_gva);
+ TEST_ASSERT(memslot[PT].gpa <= pte_gpa &&
+ pte_gpa < (memslot[PT].gpa + memslot[PT].size),
+ "The EPT should be in the PT memslot.");
+ /* This is an artibrary requirement just to make things simpler. */
+ TEST_ASSERT(pte_gpa % guest_page_size == 0,
+ "The pte_gpa (%p) should be aligned to the guest page (%lx).",
+ (void *)pte_gpa, guest_page_size);
+ virt_pg_map(vm, pte_gva, pte_gpa);
+}
+
+static void check_event_counts(struct test_desc *test)
+{
+ ASSERT_EQ(test->expected_events.aborts, events.aborts);
+}
+
+static void print_test_banner(enum vm_guest_mode mode, struct test_params *p)
+{
+ struct test_desc *test = p->test_desc;
+
+ pr_debug("Test: %s\n", test->name);
+ pr_debug("Testing guest mode: %s\n", vm_guest_mode_string(mode));
+ pr_debug("Testing memory backing src type: %s\n",
+ vm_mem_backing_src_alias(p->src_type)->name);
+}
+
+static void reset_event_counts(void)
+{
+ memset(&events, 0, sizeof(events));
+}
+
+static bool vcpu_run_loop(struct kvm_vm *vm, struct test_desc *test)
+{
+ bool skip_test = false;
+ struct ucall uc;
+ int stage;
+
+ for (stage = 0; ; stage++) {
+ vcpu_run(vm, VCPU_ID);
+
+ switch (get_ucall(vm, VCPU_ID, &uc)) {
+ case UCALL_SYNC:
+ if (uc.args[1] == CMD_SKIP_TEST) {
+ pr_debug("Skipped.\n");
+ skip_test = true;
+ goto done;
+ }
+ handle_cmd(vm, uc.args[1]);
+ break;
+ case UCALL_ABORT:
+ TEST_FAIL("%s at %s:%ld\n\tvalues: %#lx, %#lx",
+ (const char *)uc.args[0],
+ __FILE__, uc.args[1], uc.args[2], uc.args[3]);
+ break;
+ case UCALL_DONE:
+ pr_debug("Done.\n");
+ goto done;
+ default:
+ TEST_FAIL("Unknown ucall %lu", uc.cmd);
+ }
+ }
+
+done:
+ return skip_test;
+}
+
+static void run_test(enum vm_guest_mode mode, void *arg)
+{
+ struct test_params *p = (struct test_params *)arg;
+ struct test_desc *test = p->test_desc;
+ struct kvm_vm *vm;
+ bool skip_test = false;
+
+ print_test_banner(mode, p);
+
+ vm = vm_create_with_vcpus(mode, 1, DEFAULT_GUEST_PHY_PAGES,
+ get_total_guest_pages(mode, p), 0, guest_code, NULL);
+ ucall_init(vm, NULL);
+
+ reset_event_counts();
+ setup_memslots(vm, mode, p);
+
+ load_exec_code_for_test();
+ setup_abort_handlers(vm, test);
+ setup_guest_args(vm, test);
+
+ if (test->guest_pre_run)
+ test->guest_pre_run(vm);
+
+ sync_global_to_guest(vm, memslot);
+
+ skip_test = vcpu_run_loop(vm, test);
+
+ sync_stats_from_guest(vm);
+ ucall_uninit(vm);
+ kvm_vm_free(vm);
+
+ if (!skip_test)
+ check_event_counts(test);
+}
+
+static void for_each_test_and_guest_mode(void (*func)(enum vm_guest_mode, void *),
+ enum vm_mem_backing_src_type src_type);
+
+static void help(char *name)
+{
+ puts("");
+ printf("usage: %s [-h] [-s mem-type]\n", name);
+ puts("");
+ guest_modes_help();
+ backing_src_help("-s");
+ puts("");
+}
+
+int main(int argc, char *argv[])
+{
+ enum vm_mem_backing_src_type src_type;
+ int opt;
+
+ setbuf(stdout, NULL);
+
+ src_type = DEFAULT_VM_MEM_SRC;
+
+ guest_modes_append_default();
+
+ while ((opt = getopt(argc, argv, "hm:s:")) != -1) {
+ switch (opt) {
+ case 'm':
+ guest_modes_cmdline(optarg);
+ break;
+ case 's':
+ src_type = parse_backing_src_type(optarg);
+ break;
+ case 'h':
+ default:
+ help(argv[0]);
+ exit(0);
+ }
+ }
+
+ for_each_test_and_guest_mode(run_test, src_type);
+ return 0;
+}
+
+#define SNAME(s) #s
+#define SCAT(a, b) SNAME(a ## _ ## b)
+
+#define TEST_BASIC_ACCESS(__a, ...) \
+{ \
+ .name = SNAME(BASIC_ACCESS ## _ ## __a), \
+ .guest_test = __a, \
+ .expected_events = { 0 }, \
+ __VA_ARGS__ \
+}
+
+#define __AF_TEST_ARGS \
+ .guest_prepare = { guest_set_ha, guest_clear_pte_af, }, \
+ .guest_test_check = { guest_check_pte_af, }, \
+
+#define __AF_LSE_TEST_ARGS \
+ .guest_prepare = { guest_set_ha, guest_clear_pte_af, \
+ guest_check_lse, }, \
+ .guest_test_check = { guest_check_pte_af, }, \
+
+#define __PREPARE_LSE_TEST_ARGS \
+ .guest_prepare = { guest_check_lse, },
+
+#define TEST_HW_ACCESS_FLAG(__a) \
+ TEST_BASIC_ACCESS(__a, __AF_TEST_ARGS)
+
+#define TEST_ACCESS_ON_HOLE_NO_FAULTS(__a, ...) \
+{ \
+ .name = SNAME(ACCESS_ON_HOLE_NO_FAULTS ## _ ## __a), \
+ .guest_test = __a, \
+ .mem_mark_cmd = CMD_HOLE_TEST, \
+ .expected_events = { 0 }, \
+ __VA_ARGS__ \
+}
+
+static struct test_desc tests[] = {
+ /* Check that HW is setting the AF (sanity checks). */
+ TEST_HW_ACCESS_FLAG(guest_test_read64),
+ TEST_HW_ACCESS_FLAG(guest_test_ld_preidx),
+ TEST_BASIC_ACCESS(guest_test_cas, __AF_LSE_TEST_ARGS),
+ TEST_HW_ACCESS_FLAG(guest_test_write64),
+ TEST_HW_ACCESS_FLAG(guest_test_st_preidx),
+ TEST_HW_ACCESS_FLAG(guest_test_dc_zva),
+ TEST_HW_ACCESS_FLAG(guest_test_exec),
+
+ /* Accessing a hole shouldn't fault (more sanity checks). */
+ TEST_ACCESS_ON_HOLE_NO_FAULTS(guest_test_read64),
+ TEST_ACCESS_ON_HOLE_NO_FAULTS(guest_test_cas, __PREPARE_LSE_TEST_ARGS),
+ TEST_ACCESS_ON_HOLE_NO_FAULTS(guest_test_ld_preidx),
+ TEST_ACCESS_ON_HOLE_NO_FAULTS(guest_test_write64),
+ TEST_ACCESS_ON_HOLE_NO_FAULTS(guest_test_at),
+ TEST_ACCESS_ON_HOLE_NO_FAULTS(guest_test_dc_zva),
+ TEST_ACCESS_ON_HOLE_NO_FAULTS(guest_test_st_preidx),
+
+ { 0 },
+};
+
+static void for_each_test_and_guest_mode(
+ void (*func)(enum vm_guest_mode m, void *a),
+ enum vm_mem_backing_src_type src_type)
+{
+ struct test_desc *t;
+
+ for (t = &tests[0]; t->name; t++) {
+ if (t->skip)
+ continue;
+
+ struct test_params p = {
+ .src_type = src_type,
+ .test_desc = t,
+ };
+
+ for_each_guest_mode(run_test, &p);
+ }
+}
Add a new test for stage 2 faults when using different combinations of guest accesses (e.g., write, S1PTW), backing source type (e.g., anon) and types of faults (e.g., read on hugetlbfs with a hole). The next commits will add different handling methods and more faults (e.g., uffd and dirty logging). This first commit starts by adding two sanity checks for all types of accesses: AF setting by the hw, and accessing memslots with holes. Note that this commit borrows some code from kvm-unit-tests: RET, MOV_X0, and flush_tlb_page. Signed-off-by: Ricardo Koller <ricarkol@google.com> --- tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/aarch64/page_fault_test.c | 667 ++++++++++++++++++ 2 files changed, 668 insertions(+) create mode 100644 tools/testing/selftests/kvm/aarch64/page_fault_test.c