From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH 2/5] kvm/svm: enhance MOV CR intercept handler Date: Tue, 07 Dec 2010 15:24:17 +0200 Message-ID: <4CFE3581.20305@redhat.com> References: <1291719586-22533-1-git-send-email-andre.przywara@amd.com> <1291719586-22533-3-git-send-email-andre.przywara@amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org, mtosatti@redhat.com To: Andre Przywara Return-path: Received: from mx1.redhat.com ([209.132.183.28]:50089 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753083Ab0LGNYW (ORCPT ); Tue, 7 Dec 2010 08:24:22 -0500 In-Reply-To: <1291719586-22533-3-git-send-email-andre.przywara@amd.com> Sender: kvm-owner@vger.kernel.org List-ID: On 12/07/2010 12:59 PM, Andre Przywara wrote: > Newer SVM implementations provide the GPR number in the VMCB, so > that the emulation path is no longer necesarry to handle CR > register access intercepts. Implement the handling in svm.c and > use it when the info is provided. > > Signed-off-by: Andre Przywara > --- > arch/x86/include/asm/svm.h | 2 + > arch/x86/kvm/svm.c | 74 +++++++++++++++++++++++++++++++++++++++----- > 2 files changed, 68 insertions(+), 8 deletions(-) > > diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h > index 11dbca7..589fc25 100644 > --- a/arch/x86/include/asm/svm.h > +++ b/arch/x86/include/asm/svm.h > @@ -256,6 +256,8 @@ struct __attribute__ ((__packed__)) vmcb { > #define SVM_EXITINFOSHIFT_TS_REASON_JMP 38 > #define SVM_EXITINFOSHIFT_TS_HAS_ERROR_CODE 44 > > +#define SVM_EXITINFO_REG_MASK 0x0F > + > #define SVM_EXIT_READ_CR0 0x000 > #define SVM_EXIT_READ_CR3 0x003 > #define SVM_EXIT_READ_CR4 0x004 > diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c > index c573e2d..b7233fd 100644 > --- a/arch/x86/kvm/svm.c > +++ b/arch/x86/kvm/svm.c > @@ -2594,12 +2594,70 @@ static int emulate_on_interception(struct vcpu_svm *svm) > return emulate_instruction(&svm->vcpu, 0, 0, 0) == EMULATE_DONE; > } > > +static int cr_interception(struct vcpu_svm *svm) > +{ > + int reg, cr; > + unsigned long val; > + > + if (!boot_cpu_has(SVM_FEATURE_DECODE_ASSIST) || > + (svm->vmcb->control.exit_info_1& (1ULL<< 63)) == 0) > + return emulate_on_interception(svm); > + > + reg = svm->vmcb->control.exit_info_1& SVM_EXITINFO_REG_MASK; > + cr = svm->vmcb->control.exit_code - SVM_EXIT_READ_CR0; > + if (cr> 15) { /* mov to cr */ > + val = kvm_register_read(&svm->vcpu, reg); > + switch (cr& 0x0F) { > + case 0: > + kvm_set_cr0(&svm->vcpu, val); > + break; > + case 3: > + kvm_set_cr3(&svm->vcpu, val); > + break; > + case 4: > + kvm_set_cr4(&svm->vcpu, val); > + break; > + case 8: > + kvm_set_cr8(&svm->vcpu, val& 0xfUL); > + break; > + default: > + WARN(1, "unhandled write to CR%d", cr& 0x0F); > + return EMULATE_FAIL; > + } > ... > + } > + skip_emulated_instruction(&svm->vcpu); > + > + return 1; > +} > + Must not skip_emulated_instruction() if we inject an exception; see how vmx does this (handle_cr). > @@ -2864,14 +2922,14 @@ static int pause_interception(struct vcpu_svm *svm) > } > > static int (*svm_exit_handlers[])(struct vcpu_svm *svm) = { > - [SVM_EXIT_READ_CR0] = emulate_on_interception, > - [SVM_EXIT_READ_CR3] = emulate_on_interception, > - [SVM_EXIT_READ_CR4] = emulate_on_interception, > - [SVM_EXIT_READ_CR8] = emulate_on_interception, > + [SVM_EXIT_READ_CR0] = cr_interception, > + [SVM_EXIT_READ_CR3] = cr_interception, > + [SVM_EXIT_READ_CR4] = cr_interception, > + [SVM_EXIT_READ_CR8] = cr_interception, > [SVM_EXIT_CR0_SEL_WRITE] = emulate_on_interception, > [SVM_EXIT_WRITE_CR0] = cr0_write_interception, > - [SVM_EXIT_WRITE_CR3] = emulate_on_interception, > - [SVM_EXIT_WRITE_CR4] = emulate_on_interception, > + [SVM_EXIT_WRITE_CR3] = cr_interception, > + [SVM_EXIT_WRITE_CR4] = cr_interception, > [SVM_EXIT_WRITE_CR8] = cr8_write_interception, We could move cr[08]_write_interception into cr_interception, but that takes a bit more thought. Best done later. > [SVM_EXIT_READ_DR0] = emulate_on_interception, > [SVM_EXIT_READ_DR1] = emulate_on_interception, -- error compiling committee.c: too many arguments to function