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Diffstat (limited to 'arch/x86/kvm/emulate.c')
-rw-r--r--arch/x86/kvm/emulate.c108
1 files changed, 76 insertions, 32 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 3b27622d4642..4a43261d25a2 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -791,8 +791,7 @@ static int linearize(struct x86_emulate_ctxt *ctxt,
ctxt->mode, linear);
}
-static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst,
- enum x86emul_mode mode)
+static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst)
{
ulong linear;
int rc;
@@ -802,41 +801,71 @@ static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst,
if (ctxt->op_bytes != sizeof(unsigned long))
addr.ea = dst & ((1UL << (ctxt->op_bytes << 3)) - 1);
- rc = __linearize(ctxt, addr, &max_size, 1, false, true, mode, &linear);
+ rc = __linearize(ctxt, addr, &max_size, 1, false, true, ctxt->mode, &linear);
if (rc == X86EMUL_CONTINUE)
ctxt->_eip = addr.ea;
return rc;
}
+static inline int emulator_recalc_and_set_mode(struct x86_emulate_ctxt *ctxt)
+{
+ u64 efer;
+ struct desc_struct cs;
+ u16 selector;
+ u32 base3;
+
+ ctxt->ops->get_msr(ctxt, MSR_EFER, &efer);
+
+ if (!(ctxt->ops->get_cr(ctxt, 0) & X86_CR0_PE)) {
+ /* Real mode. cpu must not have long mode active */
+ if (efer & EFER_LMA)
+ return X86EMUL_UNHANDLEABLE;
+ ctxt->mode = X86EMUL_MODE_REAL;
+ return X86EMUL_CONTINUE;
+ }
+
+ if (ctxt->eflags & X86_EFLAGS_VM) {
+ /* Protected/VM86 mode. cpu must not have long mode active */
+ if (efer & EFER_LMA)
+ return X86EMUL_UNHANDLEABLE;
+ ctxt->mode = X86EMUL_MODE_VM86;
+ return X86EMUL_CONTINUE;
+ }
+
+ if (!ctxt->ops->get_segment(ctxt, &selector, &cs, &base3, VCPU_SREG_CS))
+ return X86EMUL_UNHANDLEABLE;
+
+ if (efer & EFER_LMA) {
+ if (cs.l) {
+ /* Proper long mode */
+ ctxt->mode = X86EMUL_MODE_PROT64;
+ } else if (cs.d) {
+ /* 32 bit compatibility mode*/
+ ctxt->mode = X86EMUL_MODE_PROT32;
+ } else {
+ ctxt->mode = X86EMUL_MODE_PROT16;
+ }
+ } else {
+ /* Legacy 32 bit / 16 bit mode */
+ ctxt->mode = cs.d ? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16;
+ }
+
+ return X86EMUL_CONTINUE;
+}
+
static inline int assign_eip_near(struct x86_emulate_ctxt *ctxt, ulong dst)
{
- return assign_eip(ctxt, dst, ctxt->mode);
+ return assign_eip(ctxt, dst);
}
-static int assign_eip_far(struct x86_emulate_ctxt *ctxt, ulong dst,
- const struct desc_struct *cs_desc)
+static int assign_eip_far(struct x86_emulate_ctxt *ctxt, ulong dst)
{
- enum x86emul_mode mode = ctxt->mode;
- int rc;
+ int rc = emulator_recalc_and_set_mode(ctxt);
-#ifdef CONFIG_X86_64
- if (ctxt->mode >= X86EMUL_MODE_PROT16) {
- if (cs_desc->l) {
- u64 efer = 0;
+ if (rc != X86EMUL_CONTINUE)
+ return rc;
- ctxt->ops->get_msr(ctxt, MSR_EFER, &efer);
- if (efer & EFER_LMA)
- mode = X86EMUL_MODE_PROT64;
- } else
- mode = X86EMUL_MODE_PROT32; /* temporary value */
- }
-#endif
- if (mode == X86EMUL_MODE_PROT16 || mode == X86EMUL_MODE_PROT32)
- mode = cs_desc->d ? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16;
- rc = assign_eip(ctxt, dst, mode);
- if (rc == X86EMUL_CONTINUE)
- ctxt->mode = mode;
- return rc;
+ return assign_eip(ctxt, dst);
}
static inline int jmp_rel(struct x86_emulate_ctxt *ctxt, int rel)
@@ -2172,7 +2201,7 @@ static int em_jmp_far(struct x86_emulate_ctxt *ctxt)
if (rc != X86EMUL_CONTINUE)
return rc;
- rc = assign_eip_far(ctxt, ctxt->src.val, &new_desc);
+ rc = assign_eip_far(ctxt, ctxt->src.val);
/* Error handling is not implemented. */
if (rc != X86EMUL_CONTINUE)
return X86EMUL_UNHANDLEABLE;
@@ -2250,7 +2279,7 @@ static int em_ret_far(struct x86_emulate_ctxt *ctxt)
&new_desc);
if (rc != X86EMUL_CONTINUE)
return rc;
- rc = assign_eip_far(ctxt, eip, &new_desc);
+ rc = assign_eip_far(ctxt, eip);
/* Error handling is not implemented. */
if (rc != X86EMUL_CONTINUE)
return X86EMUL_UNHANDLEABLE;
@@ -2432,7 +2461,7 @@ static int rsm_load_state_32(struct x86_emulate_ctxt *ctxt,
ctxt->eflags = GET_SMSTATE(u32, smstate, 0x7ff4) | X86_EFLAGS_FIXED;
ctxt->_eip = GET_SMSTATE(u32, smstate, 0x7ff0);
- for (i = 0; i < NR_EMULATOR_GPRS; i++)
+ for (i = 0; i < 8; i++)
*reg_write(ctxt, i) = GET_SMSTATE(u32, smstate, 0x7fd0 + i * 4);
val = GET_SMSTATE(u32, smstate, 0x7fcc);
@@ -2489,7 +2518,7 @@ static int rsm_load_state_64(struct x86_emulate_ctxt *ctxt,
u16 selector;
int i, r;
- for (i = 0; i < NR_EMULATOR_GPRS; i++)
+ for (i = 0; i < 16; i++)
*reg_write(ctxt, i) = GET_SMSTATE(u64, smstate, 0x7ff8 - i * 8);
ctxt->_eip = GET_SMSTATE(u64, smstate, 0x7f78);
@@ -2633,7 +2662,7 @@ static int em_rsm(struct x86_emulate_ctxt *ctxt)
* those side effects need to be explicitly handled for both success
* and shutdown.
*/
- return X86EMUL_CONTINUE;
+ return emulator_recalc_and_set_mode(ctxt);
emulate_shutdown:
ctxt->ops->triple_fault(ctxt);
@@ -2876,6 +2905,7 @@ static int em_sysexit(struct x86_emulate_ctxt *ctxt)
ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS);
ctxt->_eip = rdx;
+ ctxt->mode = usermode;
*reg_write(ctxt, VCPU_REGS_RSP) = rcx;
return X86EMUL_CONTINUE;
@@ -3469,7 +3499,7 @@ static int em_call_far(struct x86_emulate_ctxt *ctxt)
if (rc != X86EMUL_CONTINUE)
return rc;
- rc = assign_eip_far(ctxt, ctxt->src.val, &new_desc);
+ rc = assign_eip_far(ctxt, ctxt->src.val);
if (rc != X86EMUL_CONTINUE)
goto fail;
@@ -3611,11 +3641,25 @@ static int em_movbe(struct x86_emulate_ctxt *ctxt)
static int em_cr_write(struct x86_emulate_ctxt *ctxt)
{
- if (ctxt->ops->set_cr(ctxt, ctxt->modrm_reg, ctxt->src.val))
+ int cr_num = ctxt->modrm_reg;
+ int r;
+
+ if (ctxt->ops->set_cr(ctxt, cr_num, ctxt->src.val))
return emulate_gp(ctxt, 0);
/* Disable writeback. */
ctxt->dst.type = OP_NONE;
+
+ if (cr_num == 0) {
+ /*
+ * CR0 write might have updated CR0.PE and/or CR0.PG
+ * which can affect the cpu's execution mode.
+ */
+ r = emulator_recalc_and_set_mode(ctxt);
+ if (r != X86EMUL_CONTINUE)
+ return r;
+ }
+
return X86EMUL_CONTINUE;
}
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