Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

On 05/07/2016 07:50, Wanpeng Li wrote: >> > This needs a comment: >> > >> > /* >> > * There are two cases in which execonly is false: 1) for >> > * non-EPT page tables, in which case we need to set the >> > * P bit; 2) for EPT page tables where an X-- page

Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

On 05/07/2016 07:50, Wanpeng Li wrote: >> > This needs a comment: >> > >> > /* >> > * There are two cases in which execonly is false: 1) for >> > * non-EPT page tables, in which case we need to set the >> > * P bit; 2) for EPT page tables where an X-- page

Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

2016-06-28 16:57 GMT+08:00 Paolo Bonzini : > > > On 28/06/2016 06:32, Bandan Das wrote: >> + bool execonly = !(context->guest_rsvd_check.bad_mt_xwr & >> + (1ull << VMX_EPT_EXECUTABLE_MASK)); >> >> if (set_mmio_spte(vcpu, sptep, gfn, pfn,

Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

2016-06-28 16:57 GMT+08:00 Paolo Bonzini : > > > On 28/06/2016 06:32, Bandan Das wrote: >> + bool execonly = !(context->guest_rsvd_check.bad_mt_xwr & >> + (1ull << VMX_EPT_EXECUTABLE_MASK)); >> >> if (set_mmio_spte(vcpu, sptep, gfn, pfn, pte_access)) >>

Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

On 06/29/2016 04:18 PM, Paolo Bonzini wrote: On 29/06/2016 05:17, Xiao Guangrong wrote: +++ b/arch/x86/kvm/mmu.c @@ -2516,13 +2516,17 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, gfn_t gfn, kvm_pfn_t pfn, bool speculative, bool can_unsync, bool

Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

On 06/29/2016 04:18 PM, Paolo Bonzini wrote: On 29/06/2016 05:17, Xiao Guangrong wrote: +++ b/arch/x86/kvm/mmu.c @@ -2516,13 +2516,17 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, gfn_t gfn, kvm_pfn_t pfn, bool speculative, bool can_unsync, bool

Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

On 29/06/2016 05:17, Xiao Guangrong wrote: >> >> +++ b/arch/x86/kvm/mmu.c >> @@ -2516,13 +2516,17 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 >> *sptep, >> gfn_t gfn, kvm_pfn_t pfn, bool speculative, >> bool can_unsync, bool host_writable) >> { >> -u64

Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

On 29/06/2016 05:17, Xiao Guangrong wrote: >> >> +++ b/arch/x86/kvm/mmu.c >> @@ -2516,13 +2516,17 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 >> *sptep, >> gfn_t gfn, kvm_pfn_t pfn, bool speculative, >> bool can_unsync, bool host_writable) >> { >> -u64

Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

On 06/28/2016 12:32 PM, Bandan Das wrote: To support execute only mappings on behalf of L1 hypervisors, we teach set_spte() to honor L1's valid XWR bits. This is only if host supports EPT execute only. Reuse ACC_USER_MASK to signify if the L1 hypervisor has the R bit set Signed-off-by: Bandan

Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

On 06/28/2016 12:32 PM, Bandan Das wrote: To support execute only mappings on behalf of L1 hypervisors, we teach set_spte() to honor L1's valid XWR bits. This is only if host supports EPT execute only. Reuse ACC_USER_MASK to signify if the L1 hypervisor has the R bit set Signed-off-by: Bandan

Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

On 28/06/2016 19:30, Bandan Das wrote: > Paolo Bonzini writes: >> On 28/06/2016 06:32, Bandan Das wrote: >>> + bool execonly = !(context->guest_rsvd_check.bad_mt_xwr & >>> + (1ull << VMX_EPT_EXECUTABLE_MASK)); >>> >>> if (set_mmio_spte(vcpu,

Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

On 28/06/2016 19:30, Bandan Das wrote: > Paolo Bonzini writes: >> On 28/06/2016 06:32, Bandan Das wrote: >>> + bool execonly = !(context->guest_rsvd_check.bad_mt_xwr & >>> + (1ull << VMX_EPT_EXECUTABLE_MASK)); >>> >>> if (set_mmio_spte(vcpu, sptep, gfn, pfn,

Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

Paolo Bonzini writes: > On 28/06/2016 06:32, Bandan Das wrote: >> +bool execonly = !(context->guest_rsvd_check.bad_mt_xwr & >> + (1ull << VMX_EPT_EXECUTABLE_MASK)); >> >> if (set_mmio_spte(vcpu, sptep, gfn, pfn, pte_access)) >>

Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

Paolo Bonzini writes: > On 28/06/2016 06:32, Bandan Das wrote: >> +bool execonly = !(context->guest_rsvd_check.bad_mt_xwr & >> + (1ull << VMX_EPT_EXECUTABLE_MASK)); >> >> if (set_mmio_spte(vcpu, sptep, gfn, pfn, pte_access)) >> return 0; >> >> -

Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

On 28/06/2016 06:32, Bandan Das wrote: > + bool execonly = !(context->guest_rsvd_check.bad_mt_xwr & > + (1ull << VMX_EPT_EXECUTABLE_MASK)); > > if (set_mmio_spte(vcpu, sptep, gfn, pfn, pte_access)) > return 0; > > - spte = PT_PRESENT_MASK; >

Re: [PATCH 3/5] mmu: don't set the present bit unconditionally

On 28/06/2016 06:32, Bandan Das wrote: > + bool execonly = !(context->guest_rsvd_check.bad_mt_xwr & > + (1ull << VMX_EPT_EXECUTABLE_MASK)); > > if (set_mmio_spte(vcpu, sptep, gfn, pfn, pte_access)) > return 0; > > - spte = PT_PRESENT_MASK; >

[PATCH 3/5] mmu: don't set the present bit unconditionally

To support execute only mappings on behalf of L1 hypervisors, we teach set_spte() to honor L1's valid XWR bits. This is only if host supports EPT execute only. Reuse ACC_USER_MASK to signify if the L1 hypervisor has the R bit set Signed-off-by: Bandan Das --- arch/x86/kvm/mmu.c

[PATCH 3/5] mmu: don't set the present bit unconditionally

To support execute only mappings on behalf of L1 hypervisors, we teach set_spte() to honor L1's valid XWR bits. This is only if host supports EPT execute only. Reuse ACC_USER_MASK to signify if the L1 hypervisor has the R bit set Signed-off-by: Bandan Das --- arch/x86/kvm/mmu.c | 9