On Mon, 2021-09-13 at 17:14 +0200, Paolo Bonzini wrote: > On 13/09/21 16:55, Dave Hansen wrote: > > > By "Windows startup" I mean even after guest reboot. Because another > > > process could sneak in and steal your EPC pages between a close() and an > > > open(), I'd like to have a way to EREMOVE the pages while keeping them > > > assigned to the specific vEPC instance, i.e.*without* going through > > > sgx_vepc_free_page(). > > Oh, so you want fresh EPC state for the guest, but you're concerned that > > the previous guest might have left them in a bad state. The current > > method of getting a new vepc instance (which guarantees fresh state) has > > some other downsides. > > > > Can't another process steal pages via sgxd and reclaim at any time? > > vEPC pages never call sgx_mark_page_reclaimable, don't they? > > > What's the extra concern here about going through a close()/open() > > cycle? Performance? > > Apart from reclaiming, /dev/sgx_vepc might disappear between the first > open() and subsequent ones. If /dev/sgx_vepc dissapears, why is it a problem *for the software*, and not a sysadmin problem? I think that this is what the whole patch is lacking, why are we talking about a software problem... /Jarkko
