[PATCH] KVM: x86 emulator: Discard CR2 in x86 emulator

Sheng Yang
2007-11-16T08:30:34Z

[-- Attachment #1: Type: text/plain, Size: 4119 bytes --]

From f8aca5afbc018e71dc37d2e6001bcec376499939 Mon Sep 17 00:00:00 2001
From: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Date: Fri, 16 Nov 2007 16:29:15 +0800
Subject: [PATCH] KVM: x86 emulator: Discard CR2 in x86 emulator

For CR2 is unreliable and unavailable in many condition, this patch
completely decode memory operand instead of using CR2 in x86 emulator.

Signed-off-by: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
drivers/kvm/x86.c | 1 -
drivers/kvm/x86_emulate.c | 18 +++++++++---------
drivers/kvm/x86_emulate.h | 1 -
3 files changed, 9 insertions(+), 11 deletions(-)

diff --git a/drivers/kvm/x86.c b/drivers/kvm/x86.c
index 6d7f384..16b32bc 100644
--- a/drivers/kvm/x86.c
+++ b/drivers/kvm/x86.c
@@ -1352,7 +1352,6 @@ int emulate_instruction(struct kvm_vcpu *vcpu,

vcpu->emulate_ctxt.vcpu = vcpu;
vcpu->emulate_ctxt.eflags = kvm_x86_ops->get_rflags(vcpu);
- vcpu->emulate_ctxt.cr2 = cr2;
vcpu->emulate_ctxt.mode =
(vcpu->emulate_ctxt.eflags & X86_EFLAGS_VM)
? X86EMUL_MODE_REAL : cs_l
diff --git a/drivers/kvm/x86_emulate.c b/drivers/kvm/x86_emulate.c
index b9d2781..cbd50dd 100644
--- a/drivers/kvm/x86_emulate.c
+++ b/drivers/kvm/x86_emulate.c
@@ -1090,13 +1090,13 @@ static inline int emulate_grp45(struct
x86_emulate_ctxt *ctxt,

static inline int emulate_grp9(struct x86_emulate_ctxt *ctxt,
struct x86_emulate_ops *ops,
- unsigned long cr2)
+ unsigned long memop)
{
struct decode_cache *c = &ctxt->decode;
u64 old, new;
int rc;

- rc = ops->read_emulated(cr2, &old, 8, ctxt->vcpu);
+ rc = ops->read_emulated(memop, &old, 8, ctxt->vcpu);
if (rc != 0)
return rc;

@@ -1111,7 +1111,7 @@ static inline int emulate_grp9(struct x86_emulate_ctxt
*ctxt,
new = ((u64)c->regs[VCPU_REGS_RCX] << 32) |
(u32) c->regs[VCPU_REGS_RBX];

- rc = ops->cmpxchg_emulated(cr2, &old, &new, 8, ctxt->vcpu);
+ rc = ops->cmpxchg_emulated(memop, &old, &new, 8, ctxt->vcpu);
if (rc != 0)
return rc;
ctxt->eflags |= EFLG_ZF;
@@ -1174,7 +1174,7 @@ static inline int writeback(struct x86_emulate_ctxt
*ctxt,
int
x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
{
- unsigned long cr2 = ctxt->cr2;
+ unsigned long memop = 0;
u64 msr_data;
unsigned long saved_eip;
struct decode_cache *c = &ctxt->decode;
@@ -1189,10 +1189,10 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct
x86_emulate_ops *ops)
saved_eip = c->eip;

if (((c->d & ModRM) && (c->modrm_mod != 3)) || (c->d & MemAbs))
- cr2 = c->modrm_ea;
+ memop = c->modrm_ea;

if (c->src.type == OP_MEM) {
- c->src.ptr = (unsigned long *)cr2;
+ c->src.ptr = (unsigned long *)memop;
c->src.val = 0;
rc = ops->read_emulated((unsigned long)c->src.ptr,
&c->src.val,
@@ -1208,7 +1208,7 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct
x86_emulate_ops *ops)

if (c->dst.type == OP_MEM) {
- c->dst.ptr = (unsigned long *)cr2;
+ c->dst.ptr = (unsigned long *)memop;
c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
c->dst.val = 0;
if (c->d & BitOp) {
@@ -1647,7 +1647,7 @@ twobyte_insn:
&ctxt->eflags);
break;
case 7: /* invlpg*/
- emulate_invlpg(ctxt->vcpu, cr2);
+ emulate_invlpg(ctxt->vcpu, memop);
break;
default:
goto cannot_emulate;
@@ -1818,7 +1818,7 @@ twobyte_special_insn:
break;
}
case 0xc7: /* Grp9 (cmpxchg8b) */
- rc = emulate_grp9(ctxt, ops, cr2);
+ rc = emulate_grp9(ctxt, ops, memop);
if (rc != 0)
goto done;
break;
diff --git a/drivers/kvm/x86_emulate.h b/drivers/kvm/x86_emulate.h
index e34868b..c0a89c9 100644
--- a/drivers/kvm/x86_emulate.h
+++ b/drivers/kvm/x86_emulate.h
@@ -149,7 +149,6 @@ struct x86_emulate_ctxt {

/* Linear faulting address (if emulating a page-faulting instruction). */
unsigned long eflags;
- unsigned long cr2;

/* Emulated execution mode, represented by an X86EMUL_MODE value. */
int mode;
--
1.5.3.4

[-- Attachment #2: 0001-KVM-x86-emulator-Discard-CR2-in-x86-emulator.patch --]
[-- Type: text/x-diff, Size: 4109 bytes --]

From f8aca5afbc018e71dc37d2e6001bcec376499939 Mon Sep 17 00:00:00 2001
From: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Date: Fri, 16 Nov 2007 16:29:15 +0800
Subject: [PATCH] KVM: x86 emulator: Discard CR2 in x86 emulator

For CR2 is unreliable and unavailable in many condition, this patch
completely decode memory operand instead of using CR2 in x86 emulator.

Signed-off-by: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
drivers/kvm/x86.c | 1 -
drivers/kvm/x86_emulate.c | 18 +++++++++---------
drivers/kvm/x86_emulate.h | 1 -
3 files changed, 9 insertions(+), 11 deletions(-)

diff --git a/drivers/kvm/x86.c b/drivers/kvm/x86.c
index 6d7f384..16b32bc 100644
--- a/drivers/kvm/x86.c
+++ b/drivers/kvm/x86.c
@@ -1352,7 +1352,6 @@ int emulate_instruction(struct kvm_vcpu *vcpu,

vcpu->emulate_ctxt.vcpu = vcpu;
vcpu->emulate_ctxt.eflags = kvm_x86_ops->get_rflags(vcpu);
- vcpu->emulate_ctxt.cr2 = cr2;
vcpu->emulate_ctxt.mode =
(vcpu->emulate_ctxt.eflags & X86_EFLAGS_VM)
? X86EMUL_MODE_REAL : cs_l
diff --git a/drivers/kvm/x86_emulate.c b/drivers/kvm/x86_emulate.c
index b9d2781..cbd50dd 100644
--- a/drivers/kvm/x86_emulate.c
+++ b/drivers/kvm/x86_emulate.c
@@ -1090,13 +1090,13 @@ static inline int emulate_grp45(struct x86_emulate_ctxt *ctxt,

static inline int emulate_grp9(struct x86_emulate_ctxt *ctxt,
struct x86_emulate_ops *ops,
- unsigned long cr2)
+ unsigned long memop)
{
struct decode_cache *c = &ctxt->decode;
u64 old, new;
int rc;

- rc = ops->read_emulated(cr2, &old, 8, ctxt->vcpu);
+ rc = ops->read_emulated(memop, &old, 8, ctxt->vcpu);
if (rc != 0)
return rc;

@@ -1111,7 +1111,7 @@ static inline int emulate_grp9(struct x86_emulate_ctxt *ctxt,
new = ((u64)c->regs[VCPU_REGS_RCX] << 32) |
(u32) c->regs[VCPU_REGS_RBX];

- rc = ops->cmpxchg_emulated(cr2, &old, &new, 8, ctxt->vcpu);
+ rc = ops->cmpxchg_emulated(memop, &old, &new, 8, ctxt->vcpu);
if (rc != 0)
return rc;
ctxt->eflags |= EFLG_ZF;
@@ -1174,7 +1174,7 @@ static inline int writeback(struct x86_emulate_ctxt *ctxt,
int
x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
{
- unsigned long cr2 = ctxt->cr2;
+ unsigned long memop = 0;
u64 msr_data;
unsigned long saved_eip;
struct decode_cache *c = &ctxt->decode;
@@ -1189,10 +1189,10 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
saved_eip = c->eip;

if (((c->d & ModRM) && (c->modrm_mod != 3)) || (c->d & MemAbs))
- cr2 = c->modrm_ea;
+ memop = c->modrm_ea;

if (c->src.type == OP_MEM) {
- c->src.ptr = (unsigned long *)cr2;
+ c->src.ptr = (unsigned long *)memop;
c->src.val = 0;
rc = ops->read_emulated((unsigned long)c->src.ptr,
&c->src.val,
@@ -1208,7 +1208,7 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)

if (c->dst.type == OP_MEM) {
- c->dst.ptr = (unsigned long *)cr2;
+ c->dst.ptr = (unsigned long *)memop;
c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
c->dst.val = 0;
if (c->d & BitOp) {
@@ -1647,7 +1647,7 @@ twobyte_insn:
&ctxt->eflags);
break;
case 7: /* invlpg*/
- emulate_invlpg(ctxt->vcpu, cr2);
+ emulate_invlpg(ctxt->vcpu, memop);
break;
default:
goto cannot_emulate;
@@ -1818,7 +1818,7 @@ twobyte_special_insn:
break;
}
case 0xc7: /* Grp9 (cmpxchg8b) */
- rc = emulate_grp9(ctxt, ops, cr2);
+ rc = emulate_grp9(ctxt, ops, memop);
if (rc != 0)
goto done;
break;
diff --git a/drivers/kvm/x86_emulate.h b/drivers/kvm/x86_emulate.h
index e34868b..c0a89c9 100644
--- a/drivers/kvm/x86_emulate.h
+++ b/drivers/kvm/x86_emulate.h
@@ -149,7 +149,6 @@ struct x86_emulate_ctxt {

/* Linear faulting address (if emulating a page-faulting instruction). */
unsigned long eflags;
- unsigned long cr2;

/* Emulated execution mode, represented by an X86EMUL_MODE value. */
int mode;
--
1.5.3.4

[-- Attachment #3: Type: text/plain, Size: 228 bytes --]

-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2005.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/

[-- Attachment #4: Type: text/plain, Size: 186 bytes --]

_______________________________________________
kvm-devel mailing list
kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org