On Wed, Dec 8, 2021 at 9:53 PM Marc Orr <marcorr@xxxxxxxxxx> wrote:
>
> On Wed, Dec 8, 2021 at 11:16 AM Peter Gonda <pgonda@xxxxxxxxxx> wrote:
> >
> > Add tests to confirm mirror vms can only run correct subset of commands.
> >
> > Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> > Cc: Sean Christopherson <seanjc@xxxxxxxxxx>
> > Cc: Marc Orr <marcorr@xxxxxxxxxx>
> > Signed-off-by: Peter Gonda <pgonda@xxxxxxxxxx>
> > ---
> > .../selftests/kvm/x86_64/sev_migrate_tests.c | 55 +++++++++++++++++--
> > 1 file changed, 51 insertions(+), 4 deletions(-)
> >
> > diff --git a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> > index 4bb960ca6486..80056bbbb003 100644
> > --- a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> > +++ b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> > @@ -21,7 +21,7 @@
> > #define NR_LOCK_TESTING_THREADS 3
> > #define NR_LOCK_TESTING_ITERATIONS 10000
> >
> > -static void sev_ioctl(int vm_fd, int cmd_id, void *data)
> > +static int __sev_ioctl(int vm_fd, int cmd_id, void *data, __u32 *fw_error)
> > {
> > struct kvm_sev_cmd cmd = {
> > .id = cmd_id,
> > @@ -30,11 +30,20 @@ static void sev_ioctl(int vm_fd, int cmd_id, void *data)
> > };
> > int ret;
> >
> > -
> > ret = ioctl(vm_fd, KVM_MEMORY_ENCRYPT_OP, &cmd);
> > - TEST_ASSERT(ret == 0 && cmd.error == SEV_RET_SUCCESS,
> > + *fw_error = cmd.error;
> > + return ret;
> > +}
> > +
> > +static void sev_ioctl(int vm_fd, int cmd_id, void *data)
> > +{
> > + int ret;
> > + __u32 fw_error;
> > +
> > + ret = __sev_ioctl(vm_fd, cmd_id, data, &fw_error);
> > + TEST_ASSERT(ret == 0 && fw_error == SEV_RET_SUCCESS,
> > "%d failed: return code: %d, errno: %d, fw error: %d",
> > - cmd_id, ret, errno, cmd.error);
> > + cmd_id, ret, errno, fw_error);
> > }
> >
> > static struct kvm_vm *sev_vm_create(bool es)
> > @@ -226,6 +235,42 @@ static void sev_mirror_create(int dst_fd, int src_fd)
> > TEST_ASSERT(!ret, "Copying context failed, ret: %d, errno: %d\n", ret, errno);
> > }
> >
> > +static void verify_mirror_allowed_cmds(int vm_fd)
> > +{
> > + struct kvm_sev_guest_status status;
> > +
> > + for (int cmd_id = KVM_SEV_INIT; cmd_id < KVM_SEV_NR_MAX; ++cmd_id) {
> > + int ret;
> > + __u32 fw_error;
> > +
> > + /*
> > + * These commands are allowed for mirror VMs, all others are
> > + * not.
> > + */
> > + switch (cmd_id) {
> > + case KVM_SEV_LAUNCH_UPDATE_VMSA:
> > + case KVM_SEV_GUEST_STATUS:
> > + case KVM_SEV_DBG_DECRYPT:
> > + case KVM_SEV_DBG_ENCRYPT:
> > + continue;
> > + default:
> > + break;
> > + }
> > +
> > + /*
> > + * These commands should be disallowed before the data
> > + * parameter is examined so NULL is OK here.
> > + */
> > + ret = __sev_ioctl(vm_fd, cmd_id, NULL, &fw_error);
> > + TEST_ASSERT(
> > + ret == -1 && errno == EINVAL,
> > + "Should not be able call command: %d. ret: %d, errno: %d\n",
> > + cmd_id, ret, errno);
> > + }
> > +
> > + sev_ioctl(vm_fd, KVM_SEV_GUEST_STATUS, &status);
>
> Why is this here? I'd either delete it or maybe alternatively move it
> into the `case KVM_SEV_GUEST_STATUS` with a corresponding TEST_ASSERT
> to check that the command succeeded. Something like:
>
> ...
> switch (cmd_id) {
> case KVM_SEV_GUEST_STATUS:
> sev_ioctl(vm_fd, KVM_SEV_GUEST_STATUS, &status);
> TEST_ASSERT(ret == 0 && fw_error == SEV_RET_SUCCESS, ...);
> continue;
> case KVM_SEV_LAUNCH_UPDATE_VMSA:
> case KVM_SEV_DBG_DECRYPT:
> case KVM_SEV_DBG_ENCRYPT:
> continue;
> default:
> break;
> }
For posterity: Peter pointed out to me offline that `sev_ioctl()` in
fact does the TEST_ASSERT internally. Doh! So this line is fine as is.
