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charset=us-ascii Content-Disposition: inline In-Reply-To: <20221214194056.161492-8-michael.roth@amd.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: owa9o4r8qhf9114etsf19dedtr1tow6x X-Rspamd-Queue-Id: 08EC740019 X-HE-Tag: 1674837359-779111 X-HE-Meta: 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 64k/y9Mj NY+q7zgsbXqU4/fWQsjpDu6a5IdpGyUn1yx6M7DkF/n3w0/WEl0Arxpm/A3cptepb9qp03NxM9HzomIFTKdP7//AnpaZ4nPBaVeLXG3p08z4zX8d+0F3FQaP9uk6OeOiaW3HGz9vp6mrd/QFnVLowtBvaLIHenP+RnCPe6x2LZ4emWN1r6018bCW+axNQag6FxVdDyK8Jgza9Vj5EhTmwJHGn1d3zqvhbJ2d1 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Dec 14, 2022 at 01:39:59PM -0600, Michael Roth wrote: > From: Nikunj A Dadhania > > KVM_HC_MAP_GPA_RANGE hypercall is used by the SEV guest to notify a > change in the page encryption status to the hypervisor. > > The hypercall exits to userspace with KVM_EXIT_HYPERCALL exit code, > currently this is used for explicit memory conversion between > shared/private for memfd based private memory. > > Signed-off-by: Nikunj A Dadhania > Signed-off-by: Michael Roth > --- > arch/x86/kvm/x86.c | 8 ++++++++ > virt/kvm/kvm_main.c | 1 + > 2 files changed, 9 insertions(+) > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index bb6adb216054..732f9cbbadb5 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -9649,6 +9649,7 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) Couldn't find a better commit to comment on: when the guest has the ptp-kvm module, it will issue a KVM_HC_CLOCK_PAIRING hypercall. This will pass sev_es_validate_vmgexit validation and end up in this function where kvm_pv_clock_pairing() is called, and that calls kvm_write_guest(). This results in a CPU soft-lockup, at least in my testing. Are there any emulated hypercalls that make sense for snp guests? We should block at least the ones that definitely don't work. Jeremi > break; > case KVM_HC_MAP_GPA_RANGE: { > u64 gpa = a0, npages = a1, attrs = a2; > + struct kvm_memory_slot *slot; > > ret = -KVM_ENOSYS; > if (!(vcpu->kvm->arch.hypercall_exit_enabled & (1 << KVM_HC_MAP_GPA_RANGE))) > @@ -9660,6 +9661,13 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) > break; > } > > + slot = kvm_vcpu_gfn_to_memslot(vcpu, gpa_to_gfn(gpa)); > + if (!vcpu->kvm->arch.upm_mode || > + !kvm_slot_can_be_private(slot)) { > + ret = 0; > + break; > + } > + > vcpu->run->exit_reason = KVM_EXIT_HYPERCALL; > vcpu->run->hypercall.nr = KVM_HC_MAP_GPA_RANGE; > vcpu->run->hypercall.args[0] = gpa; > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index d2daa049e94a..73bf0bdedb59 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -2646,6 +2646,7 @@ struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn > > return NULL; > } > +EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_memslot); > > bool kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn) > { > -- > 2.25.1 >