iommufd/selftest: Add asserts testing global mfd

The mfd and mfd_buffer will be used in the tests directly without an extra
check. Test them in setup_sizes() to ensure they are safe to use.

Fixes: 0bcceb1f51c7 ("iommufd: Selftest coverage for IOMMU_IOAS_MAP_FILE")
Link: https://patch.msgid.link/r/94bdc11d2b6d5db337b1361c5e5fce0ed494bb40.1750787928.git.nicolinc@nvidia.com
Cc: stable@vger.kernel.org
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

diff --git a/tools/testing/selftests/iommu/iommufd.c b/tools/testing/selftests/iommu/iommufd.c
index e7eb11a94034001599004c1dbf79143c39a63b89..e61218c0537f22d29fa3a587d4b0d1b099cfcc5f 100644 (file)
--- a/tools/testing/selftests/iommu/iommufd.c
+++ b/tools/testing/selftests/iommu/iommufd.c
@@ -54,6 +54,8 @@ static __attribute__((constructor)) void setup_sizes(void)
 
        mfd_buffer = memfd_mmap(BUFFER_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED,
                                &mfd);
+       assert(mfd_buffer != MAP_FAILED);
+       assert(mfd > 0);
 }
 
 FIXTURE(iommufd)