As the selftest enclave is *not* intended for production, simplify the code by not initializing CPU configuration registers as expected by the ABI on enclave entry or cleansing caller-save registers on enclave exit. Link: https://lore.kernel.org/all/da0cfb1e-e347-f7f2-ac72-aec0ee0d867d@xxxxxxxxx/ Signed-off-by: Jo Van Bulck <jo.vanbulck@xxxxxxxxxxxxxx> Reviewed-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx> --- .../testing/selftests/sgx/test_encl_bootstrap.S | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) diff --git a/tools/testing/selftests/sgx/test_encl_bootstrap.S b/tools/testing/selftests/sgx/test_encl_bootstrap.S index 28fe5d2ac0af..d8c4ac94e032 100644 --- a/tools/testing/selftests/sgx/test_encl_bootstrap.S +++ b/tools/testing/selftests/sgx/test_encl_bootstrap.S @@ -59,21 +59,11 @@ encl_entry_core: push %rcx # push the address after EENTER + # NOTE: as the selftest enclave is *not* intended for production, + # simplify the code by not initializing ABI registers on entry or + # cleansing caller-save registers on exit. call encl_body - /* Clear volatile GPRs, except RAX (EEXIT function). */ - xor %rcx, %rcx - xor %rdx, %rdx - xor %rdi, %rdi - xor %rsi, %rsi - xor %r8, %r8 - xor %r9, %r9 - xor %r10, %r10 - xor %r11, %r11 - - # Reset status flags. - add %rdx, %rdx # OF = SF = AF = CF = 0; ZF = PF = 1 - # Prepare EEXIT target by popping the address of the instruction after # EENTER to RBX. pop %rbx -- 2.25.1