On Wed, 2023-11-08 at 11:17 +0000, Nicolas Saenz Julienne wrote: > The hypercall page patching is about to grow considerably, move it into > its own function. > > No functional change intended. > > Signed-off-by: Nicolas Saenz Julienne <nsaenz@xxxxxxxxxx> > --- > arch/x86/kvm/hyperv.c | 69 ++++++++++++++++++++++++------------------- > 1 file changed, 39 insertions(+), 30 deletions(-) > > diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c > index e1bc861ab3b0..78d053042667 100644 > --- a/arch/x86/kvm/hyperv.c > +++ b/arch/x86/kvm/hyperv.c > @@ -256,6 +256,42 @@ static void synic_exit(struct kvm_vcpu_hv_synic *synic, u32 msr) > kvm_make_request(KVM_REQ_HV_EXIT, vcpu); > } > > +static int patch_hypercall_page(struct kvm_vcpu *vcpu, u64 data) > +{ > + struct kvm *kvm = vcpu->kvm; > + u8 instructions[9]; > + int i = 0; > + u64 addr; > + > + /* > + * If Xen and Hyper-V hypercalls are both enabled, disambiguate > + * the same way Xen itself does, by setting the bit 31 of EAX > + * which is RsvdZ in the 32-bit Hyper-V hypercall ABI and just > + * going to be clobbered on 64-bit. > + */ > + if (kvm_xen_hypercall_enabled(kvm)) { > + /* orl $0x80000000, %eax */ > + instructions[i++] = 0x0d; > + instructions[i++] = 0x00; > + instructions[i++] = 0x00; > + instructions[i++] = 0x00; > + instructions[i++] = 0x80; > + } > + > + /* vmcall/vmmcall */ > + static_call(kvm_x86_patch_hypercall)(vcpu, instructions + i); > + i += 3; > + > + /* ret */ > + ((unsigned char *)instructions)[i++] = 0xc3; > + > + addr = data & HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_MASK; > + if (kvm_vcpu_write_guest(vcpu, addr, instructions, i)) > + return 1; > + > + return 0; > +} > + > static int synic_set_msr(struct kvm_vcpu_hv_synic *synic, > u32 msr, u64 data, bool host) > { > @@ -1338,11 +1374,7 @@ static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data, > if (!hv->hv_guest_os_id) > hv->hv_hypercall &= ~HV_X64_MSR_HYPERCALL_ENABLE; > break; > - case HV_X64_MSR_HYPERCALL: { > - u8 instructions[9]; > - int i = 0; > - u64 addr; > - > + case HV_X64_MSR_HYPERCALL: > /* if guest os id is not set hypercall should remain disabled */ > if (!hv->hv_guest_os_id) > break; > @@ -1351,34 +1383,11 @@ static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data, > break; > } > > - /* > - * If Xen and Hyper-V hypercalls are both enabled, disambiguate > - * the same way Xen itself does, by setting the bit 31 of EAX > - * which is RsvdZ in the 32-bit Hyper-V hypercall ABI and just > - * going to be clobbered on 64-bit. > - */ > - if (kvm_xen_hypercall_enabled(kvm)) { > - /* orl $0x80000000, %eax */ > - instructions[i++] = 0x0d; > - instructions[i++] = 0x00; > - instructions[i++] = 0x00; > - instructions[i++] = 0x00; > - instructions[i++] = 0x80; > - } > - > - /* vmcall/vmmcall */ > - static_call(kvm_x86_patch_hypercall)(vcpu, instructions + i); > - i += 3; > - > - /* ret */ > - ((unsigned char *)instructions)[i++] = 0xc3; > - > - addr = data & HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_MASK; > - if (kvm_vcpu_write_guest(vcpu, addr, instructions, i)) > + if (patch_hypercall_page(vcpu, data)) > return 1; > + > hv->hv_hypercall = data; > break; > - } > case HV_X64_MSR_REFERENCE_TSC: > hv->hv_tsc_page = data; > if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE) { This looks like another nice cleanup that can be accepted to the kvm, before the main VTL patch series. Reviewed-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx> Best regards, Maxim Levitsky