On 10/03/2016 09:46, Xiao Guangrong wrote: > >> Yes, all of these are needed. :) This is admittedly a bit odd, but >> kvm-unit-tests access.flat tests this if you run it with "-cpu host" >> and of course ept=0. >> >> KVM handles supervisor writes of a pte.u=0/pte.w=0/CR0.WP=0 page by >> setting U=0 and W=1 in the shadow PTE. This will cause a user write >> to fault and a supervisor write to succeed (which is correct because >> CR0.WP=0). A user read instead will flip U=0 to 1 and W=1 back to 0. > > BTW, it should be pte.u = 1 where you mentioned above.
Ok, will fix. Paolo
