diff options
Diffstat (limited to 'arch/x86/kvm')
| -rw-r--r-- | arch/x86/kvm/emulate.c | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 64c9854f045..083b269a83e 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -646,21 +646,22 @@ static unsigned long ss_base(struct x86_emulate_ctxt *ctxt) static int do_fetch_insn_byte(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops, - unsigned long linear, u8 *dest) + unsigned long eip, u8 *dest) { struct fetch_cache *fc = &ctxt->decode.fetch; int rc; - int size; + int size, cur_size; - if (linear < fc->start || linear >= fc->end) { - size = min(15UL, PAGE_SIZE - offset_in_page(linear)); - rc = ops->fetch(linear, fc->data, size, ctxt->vcpu, NULL); + if (eip == fc->end) { + cur_size = fc->end - fc->start; + size = min(15UL - cur_size, PAGE_SIZE - offset_in_page(eip)); + rc = ops->fetch(ctxt->cs_base + eip, fc->data + cur_size, + size, ctxt->vcpu, NULL); if (rc != X86EMUL_CONTINUE) return rc; - fc->start = linear; - fc->end = linear + size; + fc->end += size; } - *dest = fc->data[linear - fc->start]; + *dest = fc->data[eip - fc->start]; return X86EMUL_CONTINUE; } @@ -673,7 +674,6 @@ static int do_insn_fetch(struct x86_emulate_ctxt *ctxt, /* x86 instructions are limited to 15 bytes. */ if (eip + size - ctxt->eip > 15) return X86EMUL_UNHANDLEABLE; - eip += ctxt->cs_base; while (size--) { rc = do_fetch_insn_byte(ctxt, ops, eip++, dest++); if (rc != X86EMUL_CONTINUE) @@ -935,6 +935,7 @@ x86_decode_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) /* 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, VCPU_SREG_CS); memcpy(c->regs, ctxt->vcpu->arch.regs, sizeof c->regs); |