KVM: selftests: aarch64: Do not default to dirty PTE pages on all S1PTWs

Only Stage1 Page table walks (S1PTW) trying to write into a PTE should
result in the PTE page being dirty in the log.  However, the dirty log
tests in page_fault_test default to treat all S1PTW accesses as writes.
Fix the relevant tests by asserting dirty pages only for S1PTW writes,
which in these tests only applies to when Hardware management of the Access
Flag is enabled.
Signed-off-by: Ricardo Koller <ricarkol@google.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230127214353.245671-3-ricarkol@google.com

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

@@ -237,6 +237,11 @@ static void guest_check_s1ptw_wr_in_dirty_log(void)
 	GUEST_SYNC(CMD_CHECK_S1PTW_WR_IN_DIRTY_LOG);
 }
 
+static void guest_check_no_s1ptw_wr_in_dirty_log(void)
+{
+	GUEST_SYNC(CMD_CHECK_NO_S1PTW_WR_IN_DIRTY_LOG);
+}
+
 static void guest_exec(void)
 {
 	int (*code)(void) = (int (*)(void))TEST_EXEC_GVA;
@@ -791,7 +796,7 @@ static void help(char *name)
 	.expected_events	= { .uffd_faults = _uffd_faults, },		\
 }
 
-#define TEST_DIRTY_LOG(_access, _with_af, _test_check)				\
+#define TEST_DIRTY_LOG(_access, _with_af, _test_check, _pt_check)		\
 {										\
 	.name			= SCAT3(dirty_log, _access, _with_af),		\
 	.data_memslot_flags	= KVM_MEM_LOG_DIRTY_PAGES,			\
@@ -799,13 +804,12 @@ static void help(char *name)
 	.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},		\
+	.guest_test_check	= { _CHECK(_with_af), _test_check, _pt_check },	\
 	.expected_events	= { 0 },					\
 }
 
 #define TEST_UFFD_AND_DIRTY_LOG(_access, _with_af, _uffd_data_handler,		\
-				_uffd_faults, _test_check)			\
+				_uffd_faults, _test_check, _pt_check)		\
 {										\
 	.name			= SCAT3(uffd_and_dirty_log, _access, _with_af),	\
 	.data_memslot_flags	= KVM_MEM_LOG_DIRTY_PAGES,			\
@@ -814,7 +818,7 @@ static void help(char *name)
 				    _PREPARE(_access) },			\
 	.guest_test		= _access,					\
 	.mem_mark_cmd		= CMD_HOLE_DATA | CMD_HOLE_PT,			\
-	.guest_test_check	= { _CHECK(_with_af), _test_check },		\
+	.guest_test_check	= { _CHECK(_with_af), _test_check, _pt_check },	\
 	.uffd_data_handler	= _uffd_data_handler,				\
 	.uffd_pt_handler	= uffd_pt_handler,				\
 	.expected_events	= { .uffd_faults = _uffd_faults, },		\
@@ -953,16 +957,25 @@ static struct test_desc tests[] = {
 	 * 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),
+	TEST_DIRTY_LOG(guest_read64, with_af, guest_check_no_write_in_dirty_log,
+		       guest_check_s1ptw_wr_in_dirty_log),
+	TEST_DIRTY_LOG(guest_read64, no_af, guest_check_no_write_in_dirty_log,
+		       guest_check_no_s1ptw_wr_in_dirty_log),
+	TEST_DIRTY_LOG(guest_ld_preidx, with_af,
+		       guest_check_no_write_in_dirty_log,
+		       guest_check_s1ptw_wr_in_dirty_log),
+	TEST_DIRTY_LOG(guest_at, no_af, guest_check_no_write_in_dirty_log,
+		       guest_check_no_s1ptw_wr_in_dirty_log),
+	TEST_DIRTY_LOG(guest_exec, with_af, guest_check_no_write_in_dirty_log,
+		       guest_check_s1ptw_wr_in_dirty_log),
+	TEST_DIRTY_LOG(guest_write64, with_af, guest_check_write_in_dirty_log,
+		       guest_check_s1ptw_wr_in_dirty_log),
+	TEST_DIRTY_LOG(guest_cas, with_af, guest_check_write_in_dirty_log,
+		       guest_check_s1ptw_wr_in_dirty_log),
+	TEST_DIRTY_LOG(guest_dc_zva, with_af, guest_check_write_in_dirty_log,
+		       guest_check_s1ptw_wr_in_dirty_log),
+	TEST_DIRTY_LOG(guest_st_preidx, with_af, guest_check_write_in_dirty_log,
+		       guest_check_s1ptw_wr_in_dirty_log),
 
 	/*
 	 * Access when the data and PT memory regions are both marked for
@@ -972,27 +985,41 @@ static struct test_desc tests[] = {
 	 * fault, and nothing in the dirty log.  Any S1PTW should result in
 	 * a write in the dirty log and a userfaultfd write.
 	 */
-	TEST_UFFD_AND_DIRTY_LOG(guest_read64, with_af, uffd_data_handler, 2,
-				guest_check_no_write_in_dirty_log),
-	/* no_af should also lead to a PT write. */
-	TEST_UFFD_AND_DIRTY_LOG(guest_read64, no_af, uffd_data_handler, 2,
-				guest_check_no_write_in_dirty_log),
-	TEST_UFFD_AND_DIRTY_LOG(guest_ld_preidx, with_af, uffd_data_handler,
-				2, guest_check_no_write_in_dirty_log),
+	TEST_UFFD_AND_DIRTY_LOG(guest_read64, with_af,
+				uffd_data_handler, 2,
+				guest_check_no_write_in_dirty_log,
+				guest_check_s1ptw_wr_in_dirty_log),
+	TEST_UFFD_AND_DIRTY_LOG(guest_read64, no_af,
+				uffd_data_handler, 2,
+				guest_check_no_write_in_dirty_log,
+				guest_check_no_s1ptw_wr_in_dirty_log),
+	TEST_UFFD_AND_DIRTY_LOG(guest_ld_preidx, with_af,
+				uffd_data_handler,
+				2, guest_check_no_write_in_dirty_log,
+				guest_check_s1ptw_wr_in_dirty_log),
 	TEST_UFFD_AND_DIRTY_LOG(guest_at, with_af, uffd_no_handler, 1,
-				guest_check_no_write_in_dirty_log),
-	TEST_UFFD_AND_DIRTY_LOG(guest_exec, with_af, uffd_data_handler, 2,
-				guest_check_no_write_in_dirty_log),
-	TEST_UFFD_AND_DIRTY_LOG(guest_write64, with_af, uffd_data_handler,
-				2, guest_check_write_in_dirty_log),
-	TEST_UFFD_AND_DIRTY_LOG(guest_cas, with_af, uffd_data_handler, 2,
-				guest_check_write_in_dirty_log),
-	TEST_UFFD_AND_DIRTY_LOG(guest_dc_zva, with_af, uffd_data_handler,
-				2, guest_check_write_in_dirty_log),
+				guest_check_no_write_in_dirty_log,
+				guest_check_s1ptw_wr_in_dirty_log),
+	TEST_UFFD_AND_DIRTY_LOG(guest_exec, with_af,
+				uffd_data_handler, 2,
+				guest_check_no_write_in_dirty_log,
+				guest_check_s1ptw_wr_in_dirty_log),
+	TEST_UFFD_AND_DIRTY_LOG(guest_write64, with_af,
+				uffd_data_handler,
+				2, guest_check_write_in_dirty_log,
+				guest_check_s1ptw_wr_in_dirty_log),
+	TEST_UFFD_AND_DIRTY_LOG(guest_cas, with_af,
+				uffd_data_handler, 2,
+				guest_check_write_in_dirty_log,
+				guest_check_s1ptw_wr_in_dirty_log),
+	TEST_UFFD_AND_DIRTY_LOG(guest_dc_zva, with_af,
+				uffd_data_handler,
+				2, guest_check_write_in_dirty_log,
+				guest_check_s1ptw_wr_in_dirty_log),
 	TEST_UFFD_AND_DIRTY_LOG(guest_st_preidx, with_af,
 				uffd_data_handler, 2,
-				guest_check_write_in_dirty_log),
-
+				guest_check_write_in_dirty_log,
+				guest_check_s1ptw_wr_in_dirty_log),
 	/*
 	 * Try accesses when the data memory region is marked read-only
 	 * (with KVM_MEM_READONLY). Writes with a syndrome result in an