On Mon, Aug 07, 2023, Ackerley Tng wrote:
> Sean Christopherson <seanjc@xxxxxxxxxx> writes:
>
> > Add a selftest to verify the basic functionality of guest_memfd():
> >
> > <snip>
>
> Here's one more test:
First off, thank you! I greatly appreciate all the selftests work you (and
others!) have been doing.
For v2, can you please post a standalone patch? My workflow barfs on unrelated,
inlined patches. I'm guessing I can get b4 to play nice, but it's easier to just
yell at people :-)
> >From 72dc6836f01bdd613d64d4c6a4f2af8f2b777ba2 Mon Sep 17 00:00:00 2001
> From: Ackerley Tng <ackerleytng@xxxxxxxxxx>
> Date: Tue, 1 Aug 2023 18:02:50 +0000
> Subject: [PATCH] KVM: selftests: Add tests - invalid inputs for
> KVM_CREATE_GUEST_MEMFD
>
> Test that invalid inputs for KVM_CREATE_GUEST_MEMFD, such as
> non-page-aligned page size and invalid flags, are rejected by the
> KVM_CREATE_GUEST_MEMFD with EINVAL
>
> Signed-off-by: Ackerley Tng <ackerleytng@xxxxxxxxxx>
> ---
> tools/testing/selftests/kvm/guest_memfd_test.c | 17 +++++++++++++++++
> .../selftests/kvm/include/kvm_util_base.h | 11 +++++++++--
> 2 files changed, 26 insertions(+), 2 deletions(-)
>
> diff --git a/tools/testing/selftests/kvm/guest_memfd_test.c b/tools/testing/selftests/kvm/guest_memfd_test.c
> index eb93c608a7e0..ad20f11b2d2c 100644
> --- a/tools/testing/selftests/kvm/guest_memfd_test.c
> +++ b/tools/testing/selftests/kvm/guest_memfd_test.c
> @@ -90,6 +90,21 @@ static void test_fallocate(int fd, size_t page_size, size_t total_size)
> TEST_ASSERT(!ret, "fallocate to restore punched hole should succeed");
> }
>
> +static void test_create_guest_memfd_invalid(struct kvm_vm *vm, size_t page_size)
> +{
> + int fd;
> +
> + /* Non-page-aligned page_size */
Instead of adding a comment, use the message from TEST_ASSERT() to communicate
that information to the reader *and* to anyone that encounters failures.
> + fd = __vm_create_guest_memfd(vm, 1, 0);
ioctls() are fast. Rather than hardcode one value, iterate over a range of
values, e.g.
for (size = 0; size < page_size; size++) {
r = __vm_create_guest_memfd(vm, size, 0);
TEST_ASSERT(r && errno == EINVAL,
"Informative error message...);
}
> + ASSERT_EQ(errno, EINVAL);
> +
> + /* Invalid flags */
> + fd = __vm_create_guest_memfd(vm, page_size, 99);
> + ASSERT_EQ(fd, -1);
> + ASSERT_EQ(errno, EINVAL);
And then same thing here. Then you can use the legal flags to determine what is
and isn't valid, instead of using a completely arbitrary magic number.
