Messages in this thread | | | Date | Thu, 29 Jun 2023 23:06:24 +0800 | Subject | Re: [PATCH v1 4/6] KVM: x86: Add emulator helper for LASS violation check | From | Zeng Guang <> |
| |
On 6/28/2023 2:28 AM, Sean Christopherson wrote: > On Thu, Jun 01, 2023, Zeng Guang wrote: >> When LASS is enabled, KVM need apply LASS violation check to instruction >> emulations. Add helper for the usage of x86 emulator to perform LASS >> protection. >> >> Signed-off-by: Zeng Guang <guang.zeng@intel.com> >> Tested-by: Xuelian Guo <xuelian.guo@intel.com> >> --- >> arch/x86/kvm/kvm_emulate.h | 1 + >> arch/x86/kvm/x86.c | 12 ++++++++++++ >> 2 files changed, 13 insertions(+) >> >> diff --git a/arch/x86/kvm/kvm_emulate.h b/arch/x86/kvm/kvm_emulate.h >> index f1439ab7c14b..fd1c2b22867e 100644 >> --- a/arch/x86/kvm/kvm_emulate.h >> +++ b/arch/x86/kvm/kvm_emulate.h >> @@ -230,6 +230,7 @@ struct x86_emulate_ops { >> int (*leave_smm)(struct x86_emulate_ctxt *ctxt); >> void (*triple_fault)(struct x86_emulate_ctxt *ctxt); >> int (*set_xcr)(struct x86_emulate_ctxt *ctxt, u32 index, u64 xcr); >> + bool (*check_lass)(struct x86_emulate_ctxt *ctxt, u64 access, u64 la, u32 flags); >> }; >> >> /* Type, address-of, and value of an instruction's operand. */ >> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c >> index c0778ca39650..faf01fecc4ca 100644 >> --- a/arch/x86/kvm/x86.c >> +++ b/arch/x86/kvm/x86.c >> @@ -8287,6 +8287,17 @@ static void emulator_vm_bugged(struct x86_emulate_ctxt *ctxt) >> kvm_vm_bugged(kvm); >> } >> >> +static bool emulator_check_lass(struct x86_emulate_ctxt *ctxt, >> + u64 access, u64 la, u32 flags) >> +{ >> + struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); >> + >> + if (!is_long_mode(vcpu)) >> + return false; > Likely a moot point if we wrap ->gva_to_gpa(), but most this into the vendor > implementation. It's right way to move cpu mode check into is_lass_violation(). Previously I was struggling to expect getting benefit from separate invocation. But it doesn't help much indeed.
> > And if we keep these emulator hooks, massage the patch ordering: > > 1. Add plumbing to emulator to pass new flags > 2. Add kvm_x86_ops definition and invocation from emulator > 3. Implement and wire up vmx_is_lass_violation() > > That way the changes to each area of KVM are better isolated. OK. Will reorganize the patch accordingly. Thanks. >> + return static_call(kvm_x86_check_lass)(vcpu, access, la, flags); >> +} >> + >> static const struct x86_emulate_ops emulate_ops = { >> .vm_bugged = emulator_vm_bugged, >> .read_gpr = emulator_read_gpr, >> @@ -8332,6 +8343,7 @@ static const struct x86_emulate_ops emulate_ops = { >> .leave_smm = emulator_leave_smm, >> .triple_fault = emulator_triple_fault, >> .set_xcr = emulator_set_xcr, >> + .check_lass = emulator_check_lass, >> }; >> >> static void toggle_interruptibility(struct kvm_vcpu *vcpu, u32 mask) >> -- >> 2.27.0 >>
| |