From 34d1f4905eb66478a890ea808ec58bc842e6e589 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Thu, 26 Aug 2010 11:59:01 +0300 Subject: [PATCH] KVM: x86 emulator: trap and propagate #DE from DIV and IDIV Signed-off-by: Avi Kivity Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/emulate.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index e96cce170228..917b9b50fab0 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -504,6 +504,12 @@ static void emulate_ts(struct x86_emulate_ctxt *ctxt, int err) emulate_exception(ctxt, TS_VECTOR, err, true); } +static int emulate_de(struct x86_emulate_ctxt *ctxt) +{ + emulate_exception(ctxt, DE_VECTOR, 0, false); + return X86EMUL_PROPAGATE_FAULT; +} + static int do_fetch_insn_byte(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops, unsigned long eip, u8 *dest) @@ -1458,6 +1464,7 @@ static inline int emulate_grp3(struct x86_emulate_ctxt *ctxt, struct decode_cache *c = &ctxt->decode; unsigned long *rax = &c->regs[VCPU_REGS_RAX]; unsigned long *rdx = &c->regs[VCPU_REGS_RDX]; + u8 de = 0; switch (c->modrm_reg) { case 0 ... 1: /* test */ @@ -1476,14 +1483,18 @@ static inline int emulate_grp3(struct x86_emulate_ctxt *ctxt, emulate_1op_rax_rdx("imul", c->src, *rax, *rdx, ctxt->eflags); break; case 6: /* div */ - emulate_1op_rax_rdx("div", c->src, *rax, *rdx, ctxt->eflags); + emulate_1op_rax_rdx_ex("div", c->src, *rax, *rdx, + ctxt->eflags, de); break; case 7: /* idiv */ - emulate_1op_rax_rdx("idiv", c->src, *rax, *rdx, ctxt->eflags); + emulate_1op_rax_rdx_ex("idiv", c->src, *rax, *rdx, + ctxt->eflags, de); break; default: return X86EMUL_UNHANDLEABLE; } + if (de) + return emulate_de(ctxt); return X86EMUL_CONTINUE; } @@ -3413,8 +3424,9 @@ special_insn: ctxt->eflags ^= EFLG_CF; break; case 0xf6 ... 0xf7: /* Grp3 */ - if (emulate_grp3(ctxt, ops) != X86EMUL_CONTINUE) - goto cannot_emulate; + rc = emulate_grp3(ctxt, ops); + if (rc != X86EMUL_CONTINUE) + goto done; break; case 0xf8: /* clc */ ctxt->eflags &= ~EFLG_CF; -- 2.20.1