On Tue, Dec 18, 2018 at 06:18:15AM +0200, Jarkko Sakkinen wrote: > On Fri, Dec 14, 2018 at 01:57:24PM -0800, Sean Christopherson wrote: > > __vdso_sgx_enter_enclave() gets another rewrite, this time to strip > > it down to the bare minimum and explicitly break compliance with the > > x86-64 ABI. Feedback from v4 revealed that __vdso_sgx_enter_enclave() > > would need to save (a lot) more than just the non-volatile GPRs to be > > compliant with the x86-64 ABI, at which point breaking from the ABI > > completely became much more palatable. > > > > The non-standard ABI also solves the question of "which GPRs should be > > marshalled to/from the enclave" by getting out of the way entirely and > > letting userspace have free reign (except for RSP, which has a big ol' > > DO NOT TOUCH sign on it). > > Can you share a reference, or is this better documented in the > accompanied patches? Patch 5/5 has more details, and v4 of the series has a lot of background info by way of discussion: https://lkml.kernel.org/r/20181213213135.12913-1-sean.j.christopherson@xxxxxxxxx
