Ard, Mario, in theory, invoking EFI_RNG_PROTOCOL on a Dell Inc. Latitude 7390/09386V, BIOS 1.9.2 04/03/2019, should work fine as the system provides EFI v2.60. Using my patch from a few weeks ago[1], efi_random_get_seed() is called from arch/x86/boot/compressed/eboot.c::efi_main(). In efi_random_get_seed(), the calls to status = efi_call_early(locate_protocol, &rng_proto, NULL, (void **)&rng); and status = efi_call_early(allocate_pool, EFI_RUNTIME_SERVICES_DATA, sizeof(*seed) + EFI_RANDOM_SEED_SIZE, (void **)&seed); succeed. However, status = rng->get_rng(rng, &rng_algo_raw, EFI_RANDOM_SEED_SIZE, seed->bits); returns EFI_INVALID_PARAMETER, though I can't see why one of these parameters is invalid. When trying to use the default rng algorithm (by modifying the test to "(status != EFI_SUCCESS)"), status = rng->get_rng(rng, NULL, EFI_RANDOM_SEED_SIZE, seed->bits); the call doesn't seem to return. Any ideas? Best, Dominik [1] https://lore.kernel.org/lkml/20191005113753.GA77634@xxxxxxxxxxxxxxxxxxxxxxxxxx/
