On Thu, Jan 27, 2022 at 06:36:19AM +0000, Sean Christopherson wrote: > On Thu, Jan 27, 2022, Sean Christopherson wrote: > > Doh, I should have specified that KVM needs 8-byte CMPXCHG on 32-bit kernels due > > to using it to atomically update guest PAE PTEs and LTR descriptors (yay). > > > > Also, KVM's use case isn't a tight loop, how gross would it be to add a slightly > > less unsafe version that does __uaccess_begin_nospec()? KVM pre-checks the address > > way ahead of time, so the access_ok() check can be omitted. Alternatively, KVM > > could add its own macro, but that seems a little silly. E.g. somethign like this, > > though I don't think this is correct > > *sigh* > > Finally realized I forgot to add back the page offset after converting from guest > page frame to host virtual address. Anyways, this is what I ended up with, will > test more tomorrow. Looks about right :-) (famous last words etc..)
