Messages in this thread | | | Date | Wed, 15 Sep 2010 11:48:01 -0300 | From | Marcelo Tosatti <> | Subject | Re: [PATCH 2/2] KVM: MMU: Use base_role.nxe for mmu.nx |
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On Wed, Sep 15, 2010 at 10:48:33AM +0200, Roedel, Joerg wrote: > On Tue, Sep 14, 2010 at 06:08:37PM -0400, Marcelo Tosatti wrote: > > > > For tdp better set base_role.nxe to zero, otherwise duplicate tdp > > pagetables can be created if the guest switches between nx/non-nx. > > > > This does not work because bit 63 is marked as reserved if base_role.nxe > is 0. If the walk_addr_generic function then runs with tdp enabled it > would report a set nx bit as a rsvd fault.
Ah, OK.
> We also can't use is_nx() in those path because it does not distinguish > between l1 and l2 nx. Are there guests that switch the efer.nx bit > regularly enough so that it matters? If so I would suggest to drop this > patch and keep mmu.nx.
Well, i don't think it would be a common scenario. Ignore me.
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