From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Nadav Har'El" Subject: [PATCH 06/29] nVMX: Decoding memory operands of VMX instructions Date: Thu, 27 Jan 2011 10:32:55 +0200 Message-ID: <201101270832.p0R8Wtat002466@rice.haifa.ibm.com> References: <1296116987-nyh@il.ibm.com> Cc: gleb@redhat.com, avi@redhat.com To: kvm@vger.kernel.org Return-path: Received: from mtagate3.uk.ibm.com ([194.196.100.163]:37772 "EHLO mtagate3.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751916Ab1A0IdD (ORCPT ); Thu, 27 Jan 2011 03:33:03 -0500 Received: from d06nrmr1806.portsmouth.uk.ibm.com (d06nrmr1806.portsmouth.uk.ibm.com [9.149.39.193]) by mtagate3.uk.ibm.com (8.13.1/8.13.1) with ESMTP id p0R8Wv9j024828 for ; Thu, 27 Jan 2011 08:32:57 GMT Received: from d06av04.portsmouth.uk.ibm.com (d06av04.portsmouth.uk.ibm.com [9.149.37.216]) by d06nrmr1806.portsmouth.uk.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p0R8X0Hx1163324 for ; Thu, 27 Jan 2011 08:33:00 GMT Received: from d06av04.portsmouth.uk.ibm.com (loopback [127.0.0.1]) by d06av04.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p0R8Wv5k022811 for ; Thu, 27 Jan 2011 01:32:57 -0700 Sender: kvm-owner@vger.kernel.org List-ID: This patch includes a utility function for decoding pointer operands of VMX instructions issued by L1 (a guest hypervisor) Signed-off-by: Nadav Har'El --- arch/x86/kvm/vmx.c | 59 +++++++++++++++++++++++++++++++++++++++++++ arch/x86/kvm/x86.c | 3 +- arch/x86/kvm/x86.h | 3 ++ 3 files changed, 64 insertions(+), 1 deletion(-) --- .before/arch/x86/kvm/x86.c 2011-01-26 18:06:03.000000000 +0200 +++ .after/arch/x86/kvm/x86.c 2011-01-26 18:06:03.000000000 +0200 @@ -3686,7 +3686,7 @@ static int kvm_fetch_guest_virt(gva_t ad exception); } -static int kvm_read_guest_virt(gva_t addr, void *val, unsigned int bytes, +int kvm_read_guest_virt(gva_t addr, void *val, unsigned int bytes, struct kvm_vcpu *vcpu, struct x86_exception *exception) { @@ -3694,6 +3694,7 @@ static int kvm_read_guest_virt(gva_t add return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, access, exception); } +EXPORT_SYMBOL_GPL(kvm_read_guest_virt); static int kvm_read_guest_virt_system(gva_t addr, void *val, unsigned int bytes, struct kvm_vcpu *vcpu, --- .before/arch/x86/kvm/x86.h 2011-01-26 18:06:03.000000000 +0200 +++ .after/arch/x86/kvm/x86.h 2011-01-26 18:06:03.000000000 +0200 @@ -79,6 +79,9 @@ void kvm_before_handle_nmi(struct kvm_vc void kvm_after_handle_nmi(struct kvm_vcpu *vcpu); int kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq); +int kvm_read_guest_virt(gva_t addr, void *val, unsigned int bytes, + struct kvm_vcpu *vcpu, struct x86_exception *exception); + void kvm_write_tsc(struct kvm_vcpu *vcpu, u64 data); #endif --- .before/arch/x86/kvm/vmx.c 2011-01-26 18:06:03.000000000 +0200 +++ .after/arch/x86/kvm/vmx.c 2011-01-26 18:06:03.000000000 +0200 @@ -4063,6 +4063,65 @@ static int handle_vmoff(struct kvm_vcpu } /* + * Decode the memory-address operand of a vmx instruction, as recorded on an + * exit caused by such an instruction (run by a guest hypervisor). + * On success, returns 0. When the operand is invalid, returns 1 and throws + * #UD or #GP. + */ +static int get_vmx_mem_address(struct kvm_vcpu *vcpu, + unsigned long exit_qualification, + u32 vmx_instruction_info, gva_t *ret) +{ + /* + * According to Vol. 3B, "Information for VM Exits Due to Instruction + * Execution", on an exit, vmx_instruction_info holds most of the + * addressing components of the operand. Only the displacement part + * is put in exit_qualification (see 3B, "Basic VM-Exit Information"). + * For how an actual address is calculated from all these components, + * refer to Vol. 1, "Operand Addressing". + */ + int scaling = vmx_instruction_info & 3; + int addr_size = (vmx_instruction_info >> 7) & 7; + bool is_reg = vmx_instruction_info & (1u << 10); + int seg_reg = (vmx_instruction_info >> 15) & 7; + int index_reg = (vmx_instruction_info >> 18) & 0xf; + bool index_is_valid = !(vmx_instruction_info & (1u << 22)); + int base_reg = (vmx_instruction_info >> 23) & 0xf; + bool base_is_valid = !(vmx_instruction_info & (1u << 27)); + + if (is_reg) { + kvm_queue_exception(vcpu, UD_VECTOR); + return 1; + } + + switch (addr_size) { + case 1: /* 32 bit. high bits are undefined according to the spec: */ + exit_qualification &= 0xffffffff; + break; + case 2: /* 64 bit */ + break; + default: /* 16 bit */ + return 1; + } + + /* Addr = segment_base + offset */ + /* offset = base + [index * scale] + displacement */ + *ret = vmx_get_segment_base(vcpu, seg_reg); + if (base_is_valid) + *ret += kvm_register_read(vcpu, base_reg); + if (index_is_valid) + *ret += kvm_register_read(vcpu, index_reg)<