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KVM: x86 emulator: handle shadowed registers outside emulator

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Emulator shouldn't access vcpu directly.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Gleb Natapov
2010-04-28 19:15:42 +03:00
committed by Avi Kivity
parent bdb475a323
commit 4d2179e1e9
2 changed files with 12 additions and 17 deletions
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15
arch/x86/kvm/emulate.c
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@@ -941,12 +941,9 @@ x86_decode_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
/* we cannot decode insn before we complete previous rep insn */
WARN_ON(ctxt->restart);
/* Shadow copy of register state. Committed on successful emulation. */
memset(c, 0, sizeof(struct decode_cache));
c->eip = ctxt->eip;
c->fetch.start = c->fetch.end = c->eip;
ctxt->cs_base = seg_base(ctxt, ops, VCPU_SREG_CS);
memcpy(c->regs, ctxt->vcpu->arch.regs, sizeof c->regs);
switch (mode) {
case X86EMUL_MODE_REAL:
@@ -2486,16 +2483,13 @@ int emulator_task_switch(struct x86_emulate_ctxt *ctxt,
struct decode_cache *c = &ctxt->decode;
int rc;
memset(c, 0, sizeof(struct decode_cache));
c->eip = ctxt->eip;
memcpy(c->regs, ctxt->vcpu->arch.regs, sizeof c->regs);
c->dst.type = OP_NONE;
rc = emulator_do_task_switch(ctxt, ops, tss_selector, reason,
has_error_code, error_code);
if (rc == X86EMUL_CONTINUE) {
memcpy(ctxt->vcpu->arch.regs, c->regs, sizeof c->regs);
rc = writeback(ctxt, ops);
if (rc == X86EMUL_CONTINUE)
ctxt->eip = c->eip;
@@ -2525,13 +2519,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
ctxt->interruptibility = 0;
ctxt->decode.mem_read.pos = 0;
/* Shadow copy of register state. Committed on successful emulation.
* NOTE: we can copy them from vcpu as x86_decode_insn() doesn't
* modify them.
*/
memcpy(c->regs, ctxt->vcpu->arch.regs, sizeof c->regs);
if (ctxt->mode == X86EMUL_MODE_PROT64 && (c->d & No64)) {
kvm_queue_exception(ctxt->vcpu, UD_VECTOR);
goto done;
@@ -3031,8 +3018,6 @@ writeback:
* without decoding
*/
ctxt->decode.mem_read.end = 0;
/* Commit shadow register state. */
memcpy(ctxt->vcpu->arch.regs, c->regs, sizeof c->regs);
ctxt->eip = c->eip;
done: