> -----Original Message----- > From: Huang, Kai <[email protected]> > Sent: Thursday, August 7, 2025 3:24 AM > To: Reshetova, Elena <[email protected]>; Hansen, Dave > <[email protected]> > Cc: [email protected]; [email protected]; Scarlata, Vincent R > <[email protected]>; [email protected]; [email protected]; > Annapurve, Vishal <[email protected]>; [email protected]; > Mallick, Asit K <[email protected]>; Aktas, Erdem > <[email protected]>; Cai, Chong <[email protected]>; Bondarevska, > Nataliia <[email protected]>; [email protected]; Raynor, Scott > <[email protected]> > Subject: Re: [PATCH v11 5/5] x86/sgx: Enable automatic SVN updates for SGX > enclaves > > On Wed, 2025-08-06 at 11:11 +0300, Elena Reshetova wrote: > > == Background == > > > > ENCLS[EUPDATESVN] is a new SGX instruction [1] which allows enclave > > attestation to include information about updated microcode SVN without a > > reboot. Before an EUPDATESVN operation can be successful, all SGX memory > > (aka. EPC) must be marked as “unused” in the SGX hardware metadata > > (aka.EPCM). This requirement ensures that no compromised enclave can > > survive the EUPDATESVN procedure and provides an opportunity to generate > > new cryptographic assets. > > > > == Solution == > > > > Attempt to execute ENCLS[EUPDATESVN] every time the first file descriptor > > is obtained via sgx_(vepc_)open(). In the most common case the microcode > > SVN is already up-to-date, and the operation succeeds without updating SVN. > > A newline here would be helpful.
OK > > > Note: while in such cases the underlying CR_BASE_KEY is regenrated, it does > ^ case, since it's just one case, right? > > CR_BASE_KEY comes out of blue. And the odd is the SDM actually uses > CR_BASE_PK AFAICT, so it could bring some confusion. > > Perhaps just "crypto-assets" in general? Sure, will fix both. > > > not affect enclaves' visible keys obtained via EGETKEY instruction. > > > > If it fails with any other error code than SGX_INSUFFICIENT_ENTROPY, this > > is considered unexpected and the *open() returns an error. This should not > > happen in practice. > > > > On contrary, SGX_INSUFFICIENT_ENTROPY might happen due > > to a pressure on the system's DRNG (RDSEED) and therefore the *open() can > > be safely retried to allow normal enclave operation. > > please check text wrap. Yes, will do.
