On Fri, Mar 20, 2020 at 02:57:24AM +0200, Jarkko Sakkinen wrote: > On Wed, Mar 18, 2020 at 06:11:22PM -0700, Sean Christopherson wrote: > > Sean Christopherson (8): > > x86/sgx: vdso: Remove an incorrect statement the enter enclave comment > > x86/sgx: vdso: Make the %rsp fixup on return from handler relative > > x86/sgx: vdso: Make __vdso_sgx_enter_enclave() callable from C code > > x86/sgx: vdso: Define a typedef for __vdso_sgx_enter_enclave > > selftests/x86: sgx: Zero out @result before invoking vDSO sub-test > > selftests/x86: sgx: Pass EENTER to vDSO wrapper instead of hardcoding > > selftests/x86: sgx: Stop clobbering non-volatile registers > > selftests/x86: Add selftest to invoke __vsgx_enter_enclave() from C > > > > arch/x86/entry/vdso/vsgx_enter_enclave.S | 72 ++----------------- > > arch/x86/include/uapi/asm/sgx.h | 61 ++++++++++++++++ > > .../selftests/x86/sgx/encl_bootstrap.S | 6 +- > > tools/testing/selftests/x86/sgx/main.c | 17 ++++- > > tools/testing/selftests/x86/sgx/sgx_call.S | 1 - > > tools/testing/selftests/x86/sgx/sgx_call.h | 2 +- > > 6 files changed, 85 insertions(+), 74 deletions(-) > > > > -- > > 2.24.1 > > > > Might be a grazy idea but better to go through this anyway. > > Given the premise that we need the carry the callback anyway in all > cases, why won't just have the callback. > > Why we absolutely need the code path that fills exception info given > that we no matter what need to have a callback route? > > Would simplify considerably to have only clear flow. Invoking the callback uses a retpoline, which is non-trivial overhead. For runtimes that need an assembly wrapper for other reasons, and aren't using the untrusted stack, forcing them to implement a handler would be painful.
