hostmem-memfd: disable for systems without sealing support

If seals are not supported, memfd_create() will fail.
Furthermore, there is no way to disable it in this case because
'.seal' property is not registered.

This issue leads to vhost-user-test failures on RHEL 7.2:

  qemu-system-x86_64: -object memory-backend-memfd,id=mem,size=2M,: \
                      failed to create memfd: Invalid argument

and actually breaks the feature on such systems.

Let's restrict memfd backend to systems with sealing support.

Signed-off-by: Ilya Maximets <i.maximets@samsung.com>
Message-Id: <20190311135850.6537-2-i.maximets@samsung.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
This commit is contained in:
Ilya Maximets 2019-03-11 16:58:47 +03:00 committed by Eduardo Habkost
parent f6a0d06ba7
commit 4a66c7a999
2 changed files with 11 additions and 12 deletions

View File

@ -154,15 +154,13 @@ memfd_backend_class_init(ObjectClass *oc, void *data)
"Huge pages size (ex: 2M, 1G)",
&error_abort);
}
if (qemu_memfd_check(MFD_ALLOW_SEALING)) {
object_class_property_add_bool(oc, "seal",
memfd_backend_get_seal,
memfd_backend_set_seal,
&error_abort);
object_class_property_set_description(oc, "seal",
"Seal growing & shrinking",
&error_abort);
}
object_class_property_add_bool(oc, "seal",
memfd_backend_get_seal,
memfd_backend_set_seal,
&error_abort);
object_class_property_set_description(oc, "seal",
"Seal growing & shrinking",
&error_abort);
}
static const TypeInfo memfd_backend_info = {
@ -175,7 +173,7 @@ static const TypeInfo memfd_backend_info = {
static void register_types(void)
{
if (qemu_memfd_check(0)) {
if (qemu_memfd_check(MFD_ALLOW_SEALING)) {
type_register_static(&memfd_backend_info);
}
}

View File

@ -178,7 +178,8 @@ static void append_mem_opts(TestServer *server, GString *cmd_line,
int size, enum test_memfd memfd)
{
if (memfd == TEST_MEMFD_AUTO) {
memfd = qemu_memfd_check(0) ? TEST_MEMFD_YES : TEST_MEMFD_NO;
memfd = qemu_memfd_check(MFD_ALLOW_SEALING) ? TEST_MEMFD_YES
: TEST_MEMFD_NO;
}
if (memfd == TEST_MEMFD_YES) {
@ -930,7 +931,7 @@ static void register_vhost_user_test(void)
"virtio-net",
test_read_guest_mem, &opts);
if (qemu_memfd_check(0)) {
if (qemu_memfd_check(MFD_ALLOW_SEALING)) {
opts.before = vhost_user_test_setup_memfd;
qos_add_test("vhost-user/read-guest-mem/memfd",
"virtio-net",