On Thu, Aug 01, 2013 at 05:16:07PM +0800, Xiao Guangrong wrote: > On 07/31/2013 10:48 PM, Gleb Natapov wrote: > > From: Nadav Har'El <nyh@xxxxxxxxxx> > > > > KVM's existing shadow MMU code already supports nested TDP. To use it, we > > need to set up a new "MMU context" for nested EPT, and create a few callbacks > > for it (nested_ept_*()). This context should also use the EPT versions of > > the page table access functions (defined in the previous patch). > > Then, we need to switch back and forth between this nested context and the > > regular MMU context when switching between L1 and L2 (when L1 runs this L2 > > with EPT). > > This patch looks good to me. > > Reviewed-by: Xiao Guangrong <xiaoguangrong@xxxxxxxxxxxxxxxxxx> > > But i am confused that update_permission_bitmask() is not adjusted in this > series. That function depends on kvm_read_cr4_bits(X86_CR4_SMEP) and > is_write_protection(), these two functions should read the registers from > L2 guest, using the L2 status to check L1's page table seems strange. > The same issue is in nested npt. Anything i missed? Good catch again. Looks like we need update_permission_bitmask_ept() that uses different logic to calculate permissions. -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
