Re: [RFCv2 13/13] KVM: unmap guest memory using poisoned pages

2021-04-20 Thread Sean Christopherson
On Tue, Apr 20, 2021, Kirill A. Shutemov wrote: > On Mon, Apr 19, 2021 at 08:09:13PM +, Sean Christopherson wrote: > > On Mon, Apr 19, 2021, Kirill A. Shutemov wrote: > > > The critical question is whether we ever need to translate hva->pfn after > > > the page is added to the guest private mem

Re: [RFCv2 13/13] KVM: unmap guest memory using poisoned pages

2021-04-19 Thread Kirill A. Shutemov
On Mon, Apr 19, 2021 at 08:09:13PM +, Sean Christopherson wrote: > On Mon, Apr 19, 2021, Kirill A. Shutemov wrote: > > On Mon, Apr 19, 2021 at 06:09:29PM +, Sean Christopherson wrote: > > > On Mon, Apr 19, 2021, Kirill A. Shutemov wrote: > > > > On Mon, Apr 19, 2021 at 04:01:46PM +, Sea

Re: [RFCv2 13/13] KVM: unmap guest memory using poisoned pages

2021-04-19 Thread Sean Christopherson
On Mon, Apr 19, 2021, Kirill A. Shutemov wrote: > On Mon, Apr 19, 2021 at 06:09:29PM +, Sean Christopherson wrote: > > On Mon, Apr 19, 2021, Kirill A. Shutemov wrote: > > > On Mon, Apr 19, 2021 at 04:01:46PM +, Sean Christopherson wrote: > > > > But fundamentally the private pages, are well

Re: [RFCv2 13/13] KVM: unmap guest memory using poisoned pages

2021-04-19 Thread Kirill A. Shutemov
On Mon, Apr 19, 2021 at 06:09:29PM +, Sean Christopherson wrote: > On Mon, Apr 19, 2021, Kirill A. Shutemov wrote: > > On Mon, Apr 19, 2021 at 04:01:46PM +, Sean Christopherson wrote: > > > But fundamentally the private pages, are well, private. They can't be > > > shared > > > across pro

Re: [RFCv2 13/13] KVM: unmap guest memory using poisoned pages

2021-04-19 Thread David Hildenbrand
On 19.04.21 20:09, Sean Christopherson wrote: On Mon, Apr 19, 2021, Kirill A. Shutemov wrote: On Mon, Apr 19, 2021 at 04:01:46PM +, Sean Christopherson wrote: But fundamentally the private pages, are well, private. They can't be shared across processes, so I think we could (should?) requir

Re: [RFCv2 13/13] KVM: unmap guest memory using poisoned pages

2021-04-19 Thread Sean Christopherson
On Mon, Apr 19, 2021, Kirill A. Shutemov wrote: > On Mon, Apr 19, 2021 at 04:01:46PM +, Sean Christopherson wrote: > > But fundamentally the private pages, are well, private. They can't be > > shared > > across processes, so I think we could (should?) require the VMA to always be > > MAP_PRIV

Re: [RFCv2 13/13] KVM: unmap guest memory using poisoned pages

2021-04-19 Thread Kirill A. Shutemov
On Mon, Apr 19, 2021 at 04:01:46PM +, Sean Christopherson wrote: > On Mon, Apr 19, 2021, Kirill A. Shutemov wrote: > > On Fri, Apr 16, 2021 at 05:30:30PM +, Sean Christopherson wrote: > > > I like the idea of using "special" PTE value to denote guest private > > > memory, > > > e.g. in thi

Re: [RFCv2 13/13] KVM: unmap guest memory using poisoned pages

2021-04-19 Thread Sean Christopherson
On Mon, Apr 19, 2021, Kirill A. Shutemov wrote: > On Fri, Apr 16, 2021 at 05:30:30PM +, Sean Christopherson wrote: > > I like the idea of using "special" PTE value to denote guest private memory, > > e.g. in this RFC, HWPOISON. But I strongly dislike having KVM involved in > > the > > manipul

Re: [RFCv2 13/13] KVM: unmap guest memory using poisoned pages

2021-04-19 Thread Kirill A. Shutemov
On Fri, Apr 16, 2021 at 05:30:30PM +, Sean Christopherson wrote: > On Fri, Apr 16, 2021, Kirill A. Shutemov wrote: > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > > index 1b404e4d7dd8..f8183386abe7 100644 > > --- a/arch/x86/kvm/x86.c > > +++ b/arch/x86/kvm/x86.c > > @@ -8170,6 +8170,

Re: [RFCv2 13/13] KVM: unmap guest memory using poisoned pages

2021-04-19 Thread Xiaoyao Li
On 4/17/2021 1:30 AM, Sean Christopherson wrote: On Fri, Apr 16, 2021, Kirill A. Shutemov wrote: [...] index fadaccb95a4c..cd2374802702 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -436,6 +436,8 @@ static inline int kvm_arch_vcpu_memslots_id(struct kvm_vcpu *vcpu)

Re: [RFCv2 13/13] KVM: unmap guest memory using poisoned pages

2021-04-16 Thread Sean Christopherson
On Fri, Apr 16, 2021, Kirill A. Shutemov wrote: > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 1b404e4d7dd8..f8183386abe7 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -8170,6 +8170,12 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) > kvm_sched_

[RFCv2 13/13] KVM: unmap guest memory using poisoned pages

2021-04-16 Thread Kirill A. Shutemov
TDX architecture aims to provide resiliency against confidentiality and integrity attacks. Towards this goal, the TDX architecture helps enforce the enabling of memory integrity for all TD-private memory. The CPU memory controller computes the integrity check value (MAC) for the data (cache line)