Commit a4edf25b authored by Ricardo Koller's avatar Ricardo Koller Committed by Marc Zyngier
Browse files

KVM: selftests: aarch64: Add dirty logging tests into page_fault_test 



Add some dirty logging tests into page_fault_test. Mark the data and/or
page-table memory regions for dirty logging, perform some accesses, and
check that the dirty log bits are set or clean when expected.

Signed-off-by: default avatarRicardo Koller <ricarkol@google.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221017195834.2295901-13-ricarkol@google.com
parent 3b1d9156

tools/testing/selftests/kvm/aarch64/page_fault_test.c

+76 −0
Original line number Diff line number Diff line
@@ -31,6 +31,11 @@ static uint64_t *guest_test_memory = (uint64_t *)TEST_GVA; 
#define CMD_SKIP_TEST				(1ULL << 1)

#define CMD_HOLE_PT				(1ULL << 2)

#define CMD_HOLE_DATA				(1ULL << 3)

#define CMD_CHECK_WRITE_IN_DIRTY_LOG		(1ULL << 4)

#define CMD_CHECK_S1PTW_WR_IN_DIRTY_LOG		(1ULL << 5)

#define CMD_CHECK_NO_WRITE_IN_DIRTY_LOG		(1ULL << 6)

#define CMD_CHECK_NO_S1PTW_WR_IN_DIRTY_LOG	(1ULL << 7)

#define CMD_SET_PTE_AF				(1ULL << 8)



#define PREPARE_FN_NR				10

#define CHECK_FN_NR				10
@@ -213,6 +218,21 @@ static void guest_check_pte_af(void) 
	GUEST_ASSERT_EQ(*((uint64_t *)TEST_PTE_GVA) & PTE_AF, PTE_AF);

}



static void guest_check_write_in_dirty_log(void)

{

	GUEST_SYNC(CMD_CHECK_WRITE_IN_DIRTY_LOG);

}



static void guest_check_no_write_in_dirty_log(void)

{

	GUEST_SYNC(CMD_CHECK_NO_WRITE_IN_DIRTY_LOG);

}



static void guest_check_s1ptw_wr_in_dirty_log(void)

{

	GUEST_SYNC(CMD_CHECK_S1PTW_WR_IN_DIRTY_LOG);

}



static void guest_exec(void)

{

	int (*code)(void) = (int (*)(void))TEST_EXEC_GVA;
@@ -395,6 +415,22 @@ static bool punch_hole_in_backing_store(struct kvm_vm *vm, 
	return true;

}



static bool check_write_in_dirty_log(struct kvm_vm *vm,

				     struct userspace_mem_region *region,

				     uint64_t host_pg_nr)

{

	unsigned long *bmap;

	bool first_page_dirty;

	uint64_t size = region->region.memory_size;



	/* getpage_size() is not always equal to vm->page_size */

	bmap = bitmap_zalloc(size / getpagesize());

	kvm_vm_get_dirty_log(vm, region->region.slot, bmap);

	first_page_dirty = test_bit(host_pg_nr, bmap);

	free(bmap);

	return first_page_dirty;

}



/* Returns true to continue the test, and false if it should be skipped. */

static bool handle_cmd(struct kvm_vm *vm, int cmd)

{
@@ -411,6 +447,18 @@ static bool handle_cmd(struct kvm_vm *vm, int cmd) 
		continue_test = punch_hole_in_backing_store(vm, pt_region);

	if (cmd & CMD_HOLE_DATA)

		continue_test = punch_hole_in_backing_store(vm, data_region);

	if (cmd & CMD_CHECK_WRITE_IN_DIRTY_LOG)

		TEST_ASSERT(check_write_in_dirty_log(vm, data_region, 0),

			    "Missing write in dirty log");

	if (cmd & CMD_CHECK_S1PTW_WR_IN_DIRTY_LOG)

		TEST_ASSERT(check_write_in_dirty_log(vm, pt_region, 0),

			    "Missing s1ptw write in dirty log");

	if (cmd & CMD_CHECK_NO_WRITE_IN_DIRTY_LOG)

		TEST_ASSERT(!check_write_in_dirty_log(vm, data_region, 0),

			    "Unexpected write in dirty log");

	if (cmd & CMD_CHECK_NO_S1PTW_WR_IN_DIRTY_LOG)

		TEST_ASSERT(!check_write_in_dirty_log(vm, pt_region, 0),

			    "Unexpected s1ptw write in dirty log");



	return continue_test;

}
@@ -673,6 +721,19 @@ static void help(char *name) 
	.expected_events	= { .uffd_faults = _uffd_faults, },		\

}



#define TEST_DIRTY_LOG(_access, _with_af, _test_check)				\

{										\

	.name			= SCAT3(dirty_log, _access, _with_af),		\

	.data_memslot_flags	= KVM_MEM_LOG_DIRTY_PAGES,			\

	.pt_memslot_flags	= KVM_MEM_LOG_DIRTY_PAGES,			\

	.guest_prepare		= { _PREPARE(_with_af),				\

				    _PREPARE(_access) },			\

	.guest_test		= _access,					\

	.guest_test_check	= { _CHECK(_with_af), _test_check,		\

				    guest_check_s1ptw_wr_in_dirty_log},		\

	.expected_events	= { 0 },					\

}



static struct test_desc tests[] = {



	/* Check that HW is setting the Access Flag (AF) (sanity checks). */
@@ -732,6 +793,21 @@ static struct test_desc tests[] = { 
	TEST_UFFD(guest_exec, with_af, CMD_HOLE_DATA | CMD_HOLE_PT,

		  uffd_data_read_handler, uffd_pt_write_handler, 2),



	/*

	 * Try accesses when the data and PT memory regions are both

	 * tracked for dirty logging.

	 */

	TEST_DIRTY_LOG(guest_read64, with_af, guest_check_no_write_in_dirty_log),

	/* no_af should also lead to a PT write. */

	TEST_DIRTY_LOG(guest_read64, no_af, guest_check_no_write_in_dirty_log),

	TEST_DIRTY_LOG(guest_ld_preidx, with_af, guest_check_no_write_in_dirty_log),

	TEST_DIRTY_LOG(guest_at, no_af, guest_check_no_write_in_dirty_log),

	TEST_DIRTY_LOG(guest_exec, with_af, guest_check_no_write_in_dirty_log),

	TEST_DIRTY_LOG(guest_write64, with_af, guest_check_write_in_dirty_log),

	TEST_DIRTY_LOG(guest_cas, with_af, guest_check_write_in_dirty_log),

	TEST_DIRTY_LOG(guest_dc_zva, with_af, guest_check_write_in_dirty_log),

	TEST_DIRTY_LOG(guest_st_preidx, with_af, guest_check_write_in_dirty_log),



	{ 0 }

};