+ Cc: KVM, Paolo and Radim On Mon, 2017-11-27 at 09:03 -0800, Sean Christopherson wrote: > On Tue, 2017-11-21 at 01:08 +0200, Jarkko Sakkinen wrote: > > > > On Sat, Nov 18, 2017 at 12:34:33AM +0100, Thomas Gleixner wrote: > > > > > > > > > This is architecural. From the cursory read of that series it seems there > > > are two parts to it: > > > > > > 1) The actual core handling, which should be in arch/x86 because that > > > hardly qualifies as a 'platform' device driver. > > > > > > 2) The user space interface, which can be separated out perhaps. > > > > > > I don't know how intertwingled they are, but that's hard to tell from the > > > actual patches w/o doing a deep inspection. Jarkko should be able to > > > answer > > > that. > > > > > > Thanks, > > > > > > tglx > > Darren, tglx, > > > > You can leave user space device as separate module as sgx_ioctl.c merely > > calls stuff that I have inside sgx_encl.c. VMA creation is bound to file > > operations. > > > > My questions would be: > > > > 1. What is your recommendation on the deployment under arch/x86? > > 2. Which parts should be compilable as a LKM? Only the user interface > > or both parts? > > > > /Jarkko > To enable KVM and a cgroup for EPC accounting, at a minimum arch/x86 needs to > manage the EPC pages (alloc/free/lrus/reclaim/etc...) and LE hash MSRs. IMO, > ideally everything else would be left in the device driver, e.g. anything > involving ENCLS. Keeping the majority of the driver out of arch/x86 minimizes > the footprint in arch/x86 and thereby the size of KVM's dependency required to > virtualize SGX, and allows the various SGX pieces, e.g. arch, driver and KVM, > to evolve more independently. > > Preferably the arch/x86 code would not be a loadable module, e.g. to simplify > KVM support. > > I have a branch based on Jarkko's patches (I believe it's up-to-date with v5) > that implements what I described. I'd be happy to send RFC patches if that > would help. > > > Branches for those interested: > > https://github.com/sean-jc/linux.git sgx/arch - move core EPC to arch/x86 > https://github.com/sean-jc/linux.git sgx/kvm - KVM support for SGX > https://github.com/sean-jc/linux.git sgx/lc - KVM support for Launch > Control > https://github.com/sean-jc/linux.git sgx/cgroup - EPC cgroup > > > branch relationships: > > Jarkko's patches > | > | > sgx/arch > / \ > sgx/kvm sgx/cgroup > / > sgx/lc
