[PATCH v7 13/13] KVM: selftests: aarch64: Add mix of tests into page_fault_test

Ricardo Koller
2022-09-20T04:26:37Z

Add some mix of tests into page_fault_test: memslots with all the
pairwise combinations of read-only, userfaultfd, and dirty-logging. For
example, writing into a read-only memslot which has a hole handled with
userfaultfd.

Signed-off-by: Ricardo Koller <ricarkol@google.com>
---
.../selftests/kvm/aarch64/page_fault_test.c | 155 ++++++++++++++++++
1 file changed, 155 insertions(+)

diff --git a/tools/testing/selftests/kvm/aarch64/page_fault_test.c b/tools/testing/selftests/kvm/aarch64/page_fault_test.c
index 386c20b47723..cf72edbd42ef 100644
--- a/tools/testing/selftests/kvm/aarch64/page_fault_test.c
+++ b/tools/testing/selftests/kvm/aarch64/page_fault_test.c
@@ -399,6 +399,12 @@ static void free_uffd(struct test_desc *test, struct uffd_desc *pt_uffd,
free(data_args.copy);
}

+static int uffd_no_handler(int mode, int uffd, struct uffd_msg *msg)
+{
+ TEST_FAIL("There was no UFFD fault expected.");
+ return -1;
+}
+
/* Returns false if the test should be skipped. */
static bool punch_hole_in_memslot(struct kvm_vm *vm,
struct userspace_mem_region *region)
@@ -806,6 +812,22 @@ static void help(char *name)
.expected_events = { 0 }, \
}

+#define TEST_UFFD_AND_DIRTY_LOG(_access, _with_af, _uffd_data_handler, \
+ _uffd_faults, _test_check) \
+{ \
+ .name = SCAT3(uffd_and_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, \
+ .mem_mark_cmd = CMD_HOLE_DATA | CMD_HOLE_PT, \
+ .guest_test_check = { _CHECK(_with_af), _test_check }, \
+ .uffd_data_handler = _uffd_data_handler, \
+ .uffd_pt_handler = uffd_pt_write_handler, \
+ .expected_events = { .uffd_faults = _uffd_faults, }, \
+}
+
#define TEST_RO_MEMSLOT(_access, _mmio_handler, _mmio_exits) \
{ \
.name = SCAT3(ro_memslot, _access, _with_af), \
@@ -825,6 +847,59 @@ static void help(char *name)
.expected_events = { .fail_vcpu_runs = 1 }, \
}

+#define TEST_RO_MEMSLOT_AND_DIRTY_LOG(_access, _mmio_handler, _mmio_exits, \
+ _test_check) \
+{ \
+ .name = SCAT3(ro_memslot, _access, _with_af), \
+ .data_memslot_flags = KVM_MEM_READONLY | KVM_MEM_LOG_DIRTY_PAGES, \
+ .pt_memslot_flags = KVM_MEM_LOG_DIRTY_PAGES, \
+ .guest_prepare = { _PREPARE(_access) }, \
+ .guest_test = _access, \
+ .guest_test_check = { _test_check }, \
+ .mmio_handler = _mmio_handler, \
+ .expected_events = { .mmio_exits = _mmio_exits}, \
+}
+
+#define TEST_RO_MEMSLOT_NO_SYNDROME_AND_DIRTY_LOG(_access, _test_check) \
+{ \
+ .name = SCAT2(ro_memslot_no_syn_and_dlog, _access), \
+ .data_memslot_flags = KVM_MEM_READONLY | KVM_MEM_LOG_DIRTY_PAGES, \
+ .pt_memslot_flags = KVM_MEM_LOG_DIRTY_PAGES, \
+ .guest_test = _access, \
+ .guest_test_check = { _test_check }, \
+ .fail_vcpu_run_handler = fail_vcpu_run_mmio_no_syndrome_handler, \
+ .expected_events = { .fail_vcpu_runs = 1 }, \
+}
+
+#define TEST_RO_MEMSLOT_AND_UFFD(_access, _mmio_handler, _mmio_exits, \
+ _uffd_data_handler, _uffd_faults) \
+{ \
+ .name = SCAT2(ro_memslot_uffd, _access), \
+ .data_memslot_flags = KVM_MEM_READONLY, \
+ .mem_mark_cmd = CMD_HOLE_DATA | CMD_HOLE_PT, \
+ .guest_prepare = { _PREPARE(_access) }, \
+ .guest_test = _access, \
+ .uffd_data_handler = _uffd_data_handler, \
+ .uffd_pt_handler = uffd_pt_write_handler, \
+ .mmio_handler = _mmio_handler, \
+ .expected_events = { .mmio_exits = _mmio_exits, \
+ .uffd_faults = _uffd_faults }, \
+}
+
+#define TEST_RO_MEMSLOT_NO_SYNDROME_AND_UFFD(_access, _uffd_data_handler, \
+ _uffd_faults) \
+{ \
+ .name = SCAT2(ro_memslot_no_syndrome, _access), \
+ .data_memslot_flags = KVM_MEM_READONLY, \
+ .mem_mark_cmd = CMD_HOLE_DATA | CMD_HOLE_PT, \
+ .guest_test = _access, \
+ .uffd_data_handler = _uffd_data_handler, \
+ .uffd_pt_handler = uffd_pt_write_handler, \
+ .fail_vcpu_run_handler = fail_vcpu_run_mmio_no_syndrome_handler, \
+ .expected_events = { .fail_vcpu_runs = 1, \
+ .uffd_faults = _uffd_faults }, \
+}
+
static struct test_desc tests[] = {

/* Check that HW is setting the Access Flag (AF) (sanity checks). */
@@ -893,6 +968,35 @@ static struct test_desc tests[] = {
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),

+ /*
+ * Access when the data and PT memslots are both marked for dirty
+ * logging and UFFD at the same time. The expected result is that
+ * writes should mark the dirty log and trigger a userfaultfd write
+ * fault. Reads/execs should result in a read userfaultfd 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_read_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_read_handler, 2,
+ guest_check_no_write_in_dirty_log),
+ TEST_UFFD_AND_DIRTY_LOG(guest_ld_preidx, with_af, uffd_data_read_handler,
+ 2, guest_check_no_write_in_dirty_log),
+ TEST_UFFD_AND_DIRTY_LOG(guest_at, with_af, 0, 1,
+ guest_check_no_write_in_dirty_log),
+ TEST_UFFD_AND_DIRTY_LOG(guest_exec, with_af, uffd_data_read_handler, 2,
+ guest_check_no_write_in_dirty_log),
+ TEST_UFFD_AND_DIRTY_LOG(guest_write64, with_af, uffd_data_write_handler,
+ 2, guest_check_write_in_dirty_log),
+ TEST_UFFD_AND_DIRTY_LOG(guest_cas, with_af, uffd_data_read_handler, 2,
+ guest_check_write_in_dirty_log),
+ TEST_UFFD_AND_DIRTY_LOG(guest_dc_zva, with_af, uffd_data_write_handler,
+ 2, guest_check_write_in_dirty_log),
+ TEST_UFFD_AND_DIRTY_LOG(guest_st_preidx, with_af,
+ uffd_data_write_handler, 2,
+ guest_check_write_in_dirty_log),
+
/*
* Try accesses when the data memslot is marked read-only (with
* KVM_MEM_READONLY). Writes with a syndrome result in an MMIO exit,
@@ -908,6 +1012,57 @@ static struct test_desc tests[] = {
TEST_RO_MEMSLOT_NO_SYNDROME(guest_cas),
TEST_RO_MEMSLOT_NO_SYNDROME(guest_st_preidx),

+ /*
+ * Access when both the data memslot is both read-only and marked for
+ * dirty logging at the same time. The expected result is that for
+ * writes there should be no write in the dirty log. The readonly
+ * handling is the same as if the memslot was not marked for dirty
+ * logging: writes with a syndrome result in an MMIO exit, and writes
+ * with no syndrome result in a failed vcpu run.
+ */
+ TEST_RO_MEMSLOT_AND_DIRTY_LOG(guest_read64, 0, 0,
+ guest_check_no_write_in_dirty_log),
+ TEST_RO_MEMSLOT_AND_DIRTY_LOG(guest_ld_preidx, 0, 0,
+ guest_check_no_write_in_dirty_log),
+ TEST_RO_MEMSLOT_AND_DIRTY_LOG(guest_at, 0, 0,
+ guest_check_no_write_in_dirty_log),
+ TEST_RO_MEMSLOT_AND_DIRTY_LOG(guest_exec, 0, 0,
+ guest_check_no_write_in_dirty_log),
+ TEST_RO_MEMSLOT_AND_DIRTY_LOG(guest_write64, mmio_on_test_gpa_handler,
+ 1, guest_check_no_write_in_dirty_log),
+ TEST_RO_MEMSLOT_NO_SYNDROME_AND_DIRTY_LOG(guest_dc_zva,
+ guest_check_no_write_in_dirty_log),
+ TEST_RO_MEMSLOT_NO_SYNDROME_AND_DIRTY_LOG(guest_cas,
+ guest_check_no_write_in_dirty_log),
+ TEST_RO_MEMSLOT_NO_SYNDROME_AND_DIRTY_LOG(guest_st_preidx,
+ guest_check_no_write_in_dirty_log),
+
+ /*
+ * Access when the data memslot is both read-only and punched with
+ * holes tracked with userfaultfd. The expected result is the union of
+ * both userfaultfd and read-only behaviors. For example, write
+ * accesses result in a userfaultfd write fault and an MMIO exit.
+ * Writes with no syndrome result in a failed vcpu run and no
+ * userfaultfd write fault. Reads result in userfaultfd getting
+ * triggered.
+ */
+ TEST_RO_MEMSLOT_AND_UFFD(guest_read64, 0, 0,
+ uffd_data_read_handler, 2),
+ TEST_RO_MEMSLOT_AND_UFFD(guest_ld_preidx, 0, 0,
+ uffd_data_read_handler, 2),
+ TEST_RO_MEMSLOT_AND_UFFD(guest_at, 0, 0,
+ uffd_no_handler, 1),
+ TEST_RO_MEMSLOT_AND_UFFD(guest_exec, 0, 0,
+ uffd_data_read_handler, 2),
+ TEST_RO_MEMSLOT_AND_UFFD(guest_write64, mmio_on_test_gpa_handler, 1,
+ uffd_data_write_handler, 2),
+ TEST_RO_MEMSLOT_NO_SYNDROME_AND_UFFD(guest_cas,
+ uffd_data_read_handler, 2),
+ TEST_RO_MEMSLOT_NO_SYNDROME_AND_UFFD(guest_dc_zva,
+ uffd_no_handler, 1),
+ TEST_RO_MEMSLOT_NO_SYNDROME_AND_UFFD(guest_st_preidx,
+ uffd_no_handler, 1),
+
{ 0 }
};

--
2.37.3.968.ga6b4b080e4-goog