| Message ID | 1250599685-2351-1-git-send-email-m.gamal005@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 08/18/2009 03:48 PM, Mohammed Gamal wrote: > + > +static int emulate_pop_sreg(struct x86_emulate_ctxt *ctxt, > + struct x86_emulate_ops *ops, int seg) > +{ > + struct kvm_segment segment; > + int rc; > + > + kvm_x86_ops->get_segment(ctxt->vcpu,&segment, seg); > + rc = emulate_pop(ctxt, ops,&segment.selector, sizeof(uint16_t)); > 'pop seg' is still subject to the operand size (I think). > + kvm_x86_ops->set_segment(ctxt->vcpu,&segment, seg); > You need to call kvm_load_segment_descriptor() so that the segment cache is also loaded correctly. Note some of these instructions are not encodable in long mode; need to check for that instead of emulating the wrong instruction. > @@ -1707,18 +1732,45 @@ special_insn: > add: /* add */ > emulate_2op_SrcV("add", c->src, c->dst, ctxt->eflags); > break; > + case 0x06: /* push es */ > + emulate_push_sreg(ctxt, VCPU_SREG_ES); > + break; > + case 0x07: /* pop es */ > + rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_ES); > + if (rc != 0) > + goto done; > + break; > case 0x08 ... 0x0d: > or: /* or */ > emulate_2op_SrcV("or", c->src, c->dst, ctxt->eflags); > break; > + case 0x0e: /* push cs */ > + emulate_push_sreg(ctxt, VCPU_SREG_CS); > + break; > case 0x10 ... 0x15: > adc: /* adc */ > emulate_2op_SrcV("adc", c->src, c->dst, ctxt->eflags); > break; > + case 0x16: /* push ss */ > + emulate_push_sreg(ctxt, VCPU_SREG_SS); > + break; > + case 0x17: /* pop ss */ > + rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_SS); > + if (rc != 0) > + goto done; > + break; > case 0x18 ... 0x1d: > sbb: /* sbb */ > emulate_2op_SrcV("sbb", c->src, c->dst, ctxt->eflags); > break; > + case 0x1e: /* push ds */ > + emulate_push_sreg(ctxt, VCPU_SREG_DS); > + break; > + case 0x1f: /* pop ds */ > + rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_DS); > + if (rc != 0) > + goto done; > + break; > case 0x20 ... 0x25: > and: /* and */ > emulate_2op_SrcV("and", c->src, c->dst, ctxt->eflags); >
On Tue, Aug 18, 2009 at 5:39 PM, Avi Kivity<avi@redhat.com> wrote: > On 08/18/2009 03:48 PM, Mohammed Gamal wrote: >> >> + >> +static int emulate_pop_sreg(struct x86_emulate_ctxt *ctxt, >> + Â Â Â Â Â Â Â Â Â Â Â Â Â Â struct x86_emulate_ops *ops, int seg) >> +{ >> + Â Â Â struct kvm_segment segment; >> + Â Â Â int rc; >> + >> + Â Â Â kvm_x86_ops->get_segment(ctxt->vcpu,&segment, seg); >> + Â Â Â rc = emulate_pop(ctxt, ops,&segment.selector, sizeof(uint16_t)); >> > > 'pop seg' is still subject to the operand size (I think). > >> + Â Â Â kvm_x86_ops->set_segment(ctxt->vcpu,&segment, seg); >> But we're popping the contents of the stack top to a segment register which is going to be of 16-bits anyway, so we know the length before hand, no? > > You need to call kvm_load_segment_descriptor() so that the segment cache is > also loaded correctly. > > Note some of these instructions are not encodable in long mode; need to > check for that instead of emulating the wrong instruction. > >> @@ -1707,18 +1732,45 @@ special_insn: >> Â Â Â Â Â Â Â add: Â Â Â Â Â Â Â /* add */ >> Â Â Â Â Â Â Â Â emulate_2op_SrcV("add", c->src, c->dst, ctxt->eflags); >> Â Â Â Â Â Â Â Â break; >> + Â Â Â case 0x06: Â Â Â Â Â Â Â /* push es */ >> + Â Â Â Â Â Â Â emulate_push_sreg(ctxt, VCPU_SREG_ES); >> + Â Â Â Â Â Â Â break; >> + Â Â Â case 0x07: Â Â Â Â Â Â Â /* pop es */ >> + Â Â Â Â Â Â Â rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_ES); >> + Â Â Â Â Â Â Â if (rc != 0) >> + Â Â Â Â Â Â Â Â Â Â Â goto done; >> + Â Â Â Â Â Â Â break; >> Â Â Â Â case 0x08 ... 0x0d: >> Â Â Â Â Â Â Â or: Â Â Â Â Â Â Â /* or */ >> Â Â Â Â Â Â Â Â emulate_2op_SrcV("or", c->src, c->dst, ctxt->eflags); >> Â Â Â Â Â Â Â Â break; >> + Â Â Â case 0x0e: Â Â Â Â Â Â Â /* push cs */ >> + Â Â Â Â Â Â Â emulate_push_sreg(ctxt, VCPU_SREG_CS); >> + Â Â Â Â Â Â Â break; >> Â Â Â Â case 0x10 ... 0x15: >> Â Â Â Â Â Â Â adc: Â Â Â Â Â Â Â /* adc */ >> Â Â Â Â Â Â Â Â emulate_2op_SrcV("adc", c->src, c->dst, ctxt->eflags); >> Â Â Â Â Â Â Â Â break; >> + Â Â Â case 0x16: Â Â Â Â Â Â Â /* push ss */ >> + Â Â Â Â Â Â Â emulate_push_sreg(ctxt, VCPU_SREG_SS); >> + Â Â Â Â Â Â Â break; >> + Â Â Â case 0x17: Â Â Â Â Â Â Â /* pop ss */ >> + Â Â Â Â Â Â Â rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_SS); >> + Â Â Â Â Â Â Â if (rc != 0) >> + Â Â Â Â Â Â Â Â Â Â Â goto done; >> + Â Â Â Â Â Â Â break; >> Â Â Â Â case 0x18 ... 0x1d: >> Â Â Â Â Â Â Â sbb: Â Â Â Â Â Â Â /* sbb */ >> Â Â Â Â Â Â Â Â emulate_2op_SrcV("sbb", c->src, c->dst, ctxt->eflags); >> Â Â Â Â Â Â Â Â break; >> + Â Â Â case 0x1e: Â Â Â Â Â Â Â /* push ds */ >> + Â Â Â Â Â Â Â emulate_push_sreg(ctxt, VCPU_SREG_DS); >> + Â Â Â Â Â Â Â break; >> + Â Â Â case 0x1f: Â Â Â Â Â Â Â /* pop ds */ >> + Â Â Â Â Â Â Â rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_DS); >> + Â Â Â Â Â Â Â if (rc != 0) >> + Â Â Â Â Â Â Â Â Â Â Â goto done; >> + Â Â Â Â Â Â Â break; >> Â Â Â Â case 0x20 ... 0x25: >> Â Â Â Â Â Â Â and: Â Â Â Â Â Â Â /* and */ >> Â Â Â Â Â Â Â Â emulate_2op_SrcV("and", c->src, c->dst, ctxt->eflags); >> > > I was under the impression that the emulator doesn't support long mode yet, is that still the case? -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 08/18/2009 10:40 PM, Mohammed Gamal wrote: >> >>> + kvm_x86_ops->set_segment(ctxt->vcpu,&segment, seg); >>> >>> > But we're popping the contents of the stack top to a segment register > which is going to be of 16-bits anyway, so we know the length before > hand, no? > No, the operand size attribute determines the change to rsp. If it's larger than 2 bytes we drop the excess bits. See the documentation of the POP instruction. >> Note some of these instructions are not encodable in long mode; need to >> check for that instead of emulating the wrong instruction. >> > I was under the impression that the emulator doesn't support long mode > yet, is that still the case? > The emulator has always supported long mode, we need it for mmio and pagetable updates.
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 2eb807a..438d423 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -92,19 +92,20 @@ static u32 opcode_table[256] = { /* 0x00 - 0x07 */ ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM, - ByteOp | DstAcc | SrcImm, DstAcc | SrcImm, 0, 0, + ByteOp | DstAcc | SrcImm, DstAcc | SrcImm, + ImplicitOps | Stack, ImplicitOps | Stack, /* 0x08 - 0x0F */ ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM, - 0, 0, 0, 0, + 0, 0, ImplicitOps | Stack, 0, /* 0x10 - 0x17 */ ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM, - 0, 0, 0, 0, + 0, 0, ImplicitOps | Stack, ImplicitOps | Stack, /* 0x18 - 0x1F */ ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM, - 0, 0, 0, 0, + 0, 0, ImplicitOps | Stack, ImplicitOps | Stack, /* 0x20 - 0x27 */ ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM, @@ -1186,6 +1187,30 @@ static int emulate_pop(struct x86_emulate_ctxt *ctxt, return rc; } +static void emulate_push_sreg(struct x86_emulate_ctxt *ctxt, int seg) +{ + struct decode_cache *c = &ctxt->decode; + struct kvm_segment segment; + + kvm_x86_ops->get_segment(ctxt->vcpu, &segment, seg); + + c->src.val = segment.selector; + emulate_push(ctxt); +} + +static int emulate_pop_sreg(struct x86_emulate_ctxt *ctxt, + struct x86_emulate_ops *ops, int seg) +{ + struct kvm_segment segment; + int rc; + + kvm_x86_ops->get_segment(ctxt->vcpu, &segment, seg); + rc = emulate_pop(ctxt, ops, &segment.selector, sizeof(uint16_t)); + kvm_x86_ops->set_segment(ctxt->vcpu, &segment, seg); + + return rc; +} + static inline int emulate_grp1a(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) { @@ -1707,18 +1732,45 @@ special_insn: add: /* add */ emulate_2op_SrcV("add", c->src, c->dst, ctxt->eflags); break; + case 0x06: /* push es */ + emulate_push_sreg(ctxt, VCPU_SREG_ES); + break; + case 0x07: /* pop es */ + rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_ES); + if (rc != 0) + goto done; + break; case 0x08 ... 0x0d: or: /* or */ emulate_2op_SrcV("or", c->src, c->dst, ctxt->eflags); break; + case 0x0e: /* push cs */ + emulate_push_sreg(ctxt, VCPU_SREG_CS); + break; case 0x10 ... 0x15: adc: /* adc */ emulate_2op_SrcV("adc", c->src, c->dst, ctxt->eflags); break; + case 0x16: /* push ss */ + emulate_push_sreg(ctxt, VCPU_SREG_SS); + break; + case 0x17: /* pop ss */ + rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_SS); + if (rc != 0) + goto done; + break; case 0x18 ... 0x1d: sbb: /* sbb */ emulate_2op_SrcV("sbb", c->src, c->dst, ctxt->eflags); break; + case 0x1e: /* push ds */ + emulate_push_sreg(ctxt, VCPU_SREG_DS); + break; + case 0x1f: /* pop ds */ + rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_DS); + if (rc != 0) + goto done; + break; case 0x20 ... 0x25: and: /* and */ emulate_2op_SrcV("and", c->src, c->dst, ctxt->eflags);
Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com> --- arch/x86/kvm/emulate.c | 60 ++++++++++++++++++++++++++++++++++++++++++++--- 1 files changed, 56 insertions(+), 4 deletions(-)