TEST_ASSERT in SEV ioctl was allowing errors because it checked return
value was good OR the FW error code was OK. This TEST_ASSERT should
require both (aka. AND) values are OK. Removes the LAUNCH_START from the
mirror VM because this call correctly fails because mirror VMs cannot
call this command.
Cc: Paolo Bonzini <[email protected]>
Cc: Sean Christopherson <[email protected]>
Cc: Marc Orr <[email protected]>
Signed-off-by: Peter Gonda <[email protected]>
---
tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c | 7 ++-----
1 file changed, 2 insertions(+), 5 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 29b18d565cf4..8e1b1e737cb1 100644
--- a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
+++ b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
@@ -31,7 +31,7 @@ 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),
+ TEST_ASSERT(ret == 0 && cmd.error == SEV_RET_SUCCESS,
"%d failed: return code: %d, errno: %d, fw error: %d",
cmd_id, ret, errno, cmd.error);
}
@@ -228,9 +228,6 @@ static void sev_mirror_create(int dst_fd, int src_fd)
static void test_sev_mirror(bool es)
{
struct kvm_vm *src_vm, *dst_vm;
- struct kvm_sev_launch_start start = {
- .policy = es ? SEV_POLICY_ES : 0
- };
int i;
src_vm = sev_vm_create(es);
@@ -241,7 +238,7 @@ static void test_sev_mirror(bool es)
/* Check that we can complete creation of the mirror VM. */
for (i = 0; i < NR_MIGRATE_TEST_VCPUS; ++i)
vm_vcpu_add(dst_vm, i);
- sev_ioctl(dst_vm->fd, KVM_SEV_LAUNCH_START, &start);
+
if (es)
sev_ioctl(dst_vm->fd, KVM_SEV_LAUNCH_UPDATE_VMSA, NULL);
--
2.34.1.400.ga245620fadb-goog
On Tue, Dec 07, 2021, Peter Gonda wrote:
> TEST_ASSERT in SEV ioctl was allowing errors because it checked return
> value was good OR the FW error code was OK. This TEST_ASSERT should
> require both (aka. AND) values are OK. Removes the LAUNCH_START from the
> mirror VM because this call correctly fails because mirror VMs cannot
> call this command.
This probably should be two separate patches. First remove the bogus LAUNCH_START
call, then fix the assert.
> Cc: Paolo Bonzini <[email protected]>
> Cc: Sean Christopherson <[email protected]>
> Cc: Marc Orr <[email protected]>
> Signed-off-by: Peter Gonda <[email protected]>
> ---
> tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c | 7 ++-----
> 1 file changed, 2 insertions(+), 5 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 29b18d565cf4..8e1b1e737cb1 100644
> --- a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> +++ b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> @@ -31,7 +31,7 @@ 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),
> + TEST_ASSERT(ret == 0 && cmd.error == SEV_RET_SUCCESS,
> "%d failed: return code: %d, errno: %d, fw error: %d",
> cmd_id, ret, errno, cmd.error);
Hmm, reading cmd.error could also consume uninitialized data, e.g. if the ioctl()
fails before getting into the PSP command, the error message will dump garbage.
And theoretically this could get a false negative if the test stack happens to have
'0' for cmd.error and KVM neglects to fill cmd.error when the ioctl() succeeds.
So in additional to fixing the assert itself, I vote we also do:
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 29b18d565cf4..50132e165a8d 100644
--- a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
+++ b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
@@ -26,6 +26,7 @@ static void sev_ioctl(int vm_fd, int cmd_id, void *data)
struct kvm_sev_cmd cmd = {
.id = cmd_id,
.data = (uint64_t)data,
+ .error = -1u,
.sev_fd = open_sev_dev_path_or_exit(),
};
int ret;
On Tue, Dec 7, 2021 at 2:25 PM Sean Christopherson <[email protected]> wrote:
>
> On Tue, Dec 07, 2021, Peter Gonda wrote:
> > TEST_ASSERT in SEV ioctl was allowing errors because it checked return
> > value was good OR the FW error code was OK. This TEST_ASSERT should
> > require both (aka. AND) values are OK. Removes the LAUNCH_START from the
> > mirror VM because this call correctly fails because mirror VMs cannot
> > call this command.
>
> This probably should be two separate patches. First remove the bogus LAUNCH_START
> call, then fix the assert.
Thanks Sean. I'll split the patch and add your suggestion to the second one.
>
> > Cc: Paolo Bonzini <[email protected]>
> > Cc: Sean Christopherson <[email protected]>
> > Cc: Marc Orr <[email protected]>
> > Signed-off-by: Peter Gonda <[email protected]>
> > ---
> > tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c | 7 ++-----
> > 1 file changed, 2 insertions(+), 5 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 29b18d565cf4..8e1b1e737cb1 100644
> > --- a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> > +++ b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> > @@ -31,7 +31,7 @@ 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),
> > + TEST_ASSERT(ret == 0 && cmd.error == SEV_RET_SUCCESS,
> > "%d failed: return code: %d, errno: %d, fw error: %d",
> > cmd_id, ret, errno, cmd.error);
>
> Hmm, reading cmd.error could also consume uninitialized data, e.g. if the ioctl()
> fails before getting into the PSP command, the error message will dump garbage.
>
> And theoretically this could get a false negative if the test stack happens to have
> '0' for cmd.error and KVM neglects to fill cmd.error when the ioctl() succeeds.
>
> So in additional to fixing the assert itself, I vote we also do:
>
> 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 29b18d565cf4..50132e165a8d 100644
> --- a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> +++ b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> @@ -26,6 +26,7 @@ static void sev_ioctl(int vm_fd, int cmd_id, void *data)
> struct kvm_sev_cmd cmd = {
> .id = cmd_id,
> .data = (uint64_t)data,
> + .error = -1u,
> .sev_fd = open_sev_dev_path_or_exit(),
> };
> int ret;
Good idea will do in the 2/2.
On Tue, Dec 7, 2021 at 12:10 PM Peter Gonda <[email protected]> wrote:
>
> TEST_ASSERT in SEV ioctl was allowing errors because it checked return
> value was good OR the FW error code was OK. This TEST_ASSERT should
> require both (aka. AND) values are OK. Removes the LAUNCH_START from the
> mirror VM because this call correctly fails because mirror VMs cannot
> call this command.
>
> Cc: Paolo Bonzini <[email protected]>
> Cc: Sean Christopherson <[email protected]>
> Cc: Marc Orr <[email protected]>
> Signed-off-by: Peter Gonda <[email protected]>
> ---
> tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c | 7 ++-----
> 1 file changed, 2 insertions(+), 5 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 29b18d565cf4..8e1b1e737cb1 100644
> --- a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> +++ b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> @@ -31,7 +31,7 @@ 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),
> + TEST_ASSERT(ret == 0 && cmd.error == SEV_RET_SUCCESS,
> "%d failed: return code: %d, errno: %d, fw error: %d",
> cmd_id, ret, errno, cmd.error);
> }
> @@ -228,9 +228,6 @@ static void sev_mirror_create(int dst_fd, int src_fd)
> static void test_sev_mirror(bool es)
> {
> struct kvm_vm *src_vm, *dst_vm;
> - struct kvm_sev_launch_start start = {
> - .policy = es ? SEV_POLICY_ES : 0
> - };
> int i;
>
> src_vm = sev_vm_create(es);
> @@ -241,7 +238,7 @@ static void test_sev_mirror(bool es)
> /* Check that we can complete creation of the mirror VM. */
> for (i = 0; i < NR_MIGRATE_TEST_VCPUS; ++i)
> vm_vcpu_add(dst_vm, i);
> - sev_ioctl(dst_vm->fd, KVM_SEV_LAUNCH_START, &start);
> +
> if (es)
> sev_ioctl(dst_vm->fd, KVM_SEV_LAUNCH_UPDATE_VMSA, NULL);
>
> --
> 2.34.1.400.ga245620fadb-goog
>
+1 to Sean's feedback.
Otherwise:
Reviewed-by: Marc Orr <[email protected]>