On Fri, Dec 10, 2010 at 02:51:25PM +0100, 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 <[email protected]> > --- > arch/x86/include/asm/svm.h | 2 + > arch/x86/kvm/svm.c | 91 ++++++++++++++++++++++++++++++++++++++----- > 2 files changed, 82 insertions(+), 11 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 298ff79..ee5f100 100644 > --- a/arch/x86/kvm/svm.c > +++ b/arch/x86/kvm/svm.c > @@ -2594,12 +2594,81 @@ 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; > + int err; > + > + if (!static_cpu_has(X86_FEATURE_DECODEASSISTS)) > + return emulate_on_interception(svm); > + > + /* bit 63 is the valid bit, as not all instructions (like lmsw) > + provide the information */ > + if (unlikely((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; > + > + err = 0; > + if (cr >= 16) { /* mov to cr */ > + cr -= 16; > + val = kvm_register_read(&svm->vcpu, reg); > + switch (cr) { > + case 0: > + err = kvm_set_cr0(&svm->vcpu, val); > + break; > + case 3: > + err = kvm_set_cr3(&svm->vcpu, val); > + break; > + case 4: > + err = kvm_set_cr4(&svm->vcpu, val); > + break; > + case 8: > + err = kvm_set_cr8(&svm->vcpu, val); > + break; > + default: > + WARN(1, "unhandled write to CR%d", cr); > + return EMULATE_FAIL; > + }
Wrong return value? Is WARN() really wanted? -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
