Messages in this thread | | | Subject | Re: [RFC PATCH 3/3] nSVM: use svm->nested.save to load vmcb12 registers and avoid TOC/TOU races | From | Maxim Levitsky <> | Date | Tue, 14 Sep 2021 12:02:28 +0300 |
| |
On Tue, 2021-09-14 at 10:20 +0200, Emanuele Giuseppe Esposito wrote: > > On 12/09/2021 12:42, Maxim Levitsky wrote: > > > > > > - if (!nested_vmcb_valid_sregs(vcpu, &vmcb12->save) || > > > + if (!nested_vmcb_valid_sregs(vcpu, &svm->nested.save) || > > > !nested_vmcb_check_controls(vcpu, &svm->nested.ctl)) { > > If you use a different struct for the copied fields, then it makes > > sense IMHO to drop the 'control' parameter from nested_vmcb_check_controls, > > and just use the svm->nested.save there directly. > > > > Ok, what you say in patch 2 makes sense to me. I can create a new struct > vmcb_save_area_cached, but I need to keep nested.ctl because 1) it is > used also elsewhere, and different fields from the one checked here are > read/set and 2) using another structure (or the same
Yes, keep nested.ctl, since vast majority of the fields are copied I think.
Best regards, Maxim Levitsky
> vmcb_save_area_cached) in its place would just duplicate the same fields > of nested.ctl, creating even more confusion and possible inconsistency. > > Let me know if you disagree. > > Thank you, > Emanuele >
| |