From da9cb575b1127f84984b8ad6d973dcc05ac036dd Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Mon, 22 Nov 2010 17:53:21 +0200 Subject: [PATCH] KVM: x86 emulator: introduce struct x86_exception to communicate faults Introduce a structure that can contain an exception to be passed back to main kvm code. Signed-off-by: Avi Kivity Signed-off-by: Marcelo Tosatti --- arch/x86/include/asm/kvm_emulate.h | 11 ++++++++--- arch/x86/kvm/emulate.c | 26 +++++++++++++++++++++++--- arch/x86/kvm/x86.c | 13 +++++++------ 3 files changed, 38 insertions(+), 12 deletions(-) diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h index b48c133..b7c1127 100644 --- a/arch/x86/include/asm/kvm_emulate.h +++ b/arch/x86/include/asm/kvm_emulate.h @@ -15,6 +15,12 @@ struct x86_emulate_ctxt; +struct x86_exception { + u8 vector; + bool error_code_valid; + u16 error_code; +}; + /* * x86_emulate_ops: * @@ -229,9 +235,8 @@ struct x86_emulate_ctxt { bool perm_ok; /* do not check permissions if true */ - int exception; /* exception that happens during emulation or -1 */ - u32 error_code; /* error code for exception */ - bool error_code_valid; + bool have_exception; + struct x86_exception exception; /* decode cache */ struct decode_cache decode; diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index bdbbb18..18596e6 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -469,9 +469,9 @@ static ulong linear(struct x86_emulate_ctxt *ctxt, static void emulate_exception(struct x86_emulate_ctxt *ctxt, int vec, u32 error, bool valid) { - ctxt->exception = vec; - ctxt->error_code = error; - ctxt->error_code_valid = valid; + ctxt->exception.vector = vec; + ctxt->exception.error_code = error; + ctxt->exception.error_code_valid = valid; } static void emulate_gp(struct x86_emulate_ctxt *ctxt, int err) @@ -3015,23 +3015,27 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt) if (ctxt->mode == X86EMUL_MODE_PROT64 && (c->d & No64)) { emulate_ud(ctxt); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } /* LOCK prefix is allowed only with some instructions */ if (c->lock_prefix && (!(c->d & Lock) || c->dst.type != OP_MEM)) { emulate_ud(ctxt); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } if ((c->d & SrcMask) == SrcMemFAddr && c->src.type != OP_MEM) { emulate_ud(ctxt); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } /* Privileged instruction can be executed only in CPL=0 */ if ((c->d & Priv) && ops->cpl(ctxt->vcpu)) { emulate_gp(ctxt, 0); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } @@ -3210,6 +3214,7 @@ special_insn: case 0x8c: /* mov r/m, sreg */ if (c->modrm_reg > VCPU_SREG_GS) { emulate_ud(ctxt); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } c->dst.val = ops->get_segment_selector(c->modrm_reg, ctxt->vcpu); @@ -3225,6 +3230,7 @@ special_insn: if (c->modrm_reg == VCPU_SREG_CS || c->modrm_reg > VCPU_SREG_GS) { emulate_ud(ctxt); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } @@ -3357,6 +3363,7 @@ special_insn: c->dst.bytes = min(c->dst.bytes, 4u); if (!emulator_io_permited(ctxt, ops, c->src.val, c->dst.bytes)) { emulate_gp(ctxt, 0); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } if (!pio_in_emulated(ctxt, ops, c->dst.bytes, c->src.val, @@ -3371,6 +3378,7 @@ special_insn: if (!emulator_io_permited(ctxt, ops, c->dst.val, c->src.bytes)) { emulate_gp(ctxt, 0); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } ops->pio_out_emulated(c->src.bytes, c->dst.val, @@ -3396,6 +3404,7 @@ special_insn: case 0xfa: /* cli */ if (emulator_bad_iopl(ctxt, ops)) { emulate_gp(ctxt, 0); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } else ctxt->eflags &= ~X86_EFLAGS_IF; @@ -3403,6 +3412,7 @@ special_insn: case 0xfb: /* sti */ if (emulator_bad_iopl(ctxt, ops)) { emulate_gp(ctxt, 0); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } else { ctxt->interruptibility = KVM_X86_SHADOW_INT_STI; @@ -3475,6 +3485,8 @@ writeback: ctxt->eip = c->eip; done: + if (rc == X86EMUL_PROPAGATE_FAULT) + ctxt->have_exception = true; return (rc == X86EMUL_UNHANDLEABLE) ? EMULATION_FAILED : EMULATION_OK; twobyte_insn: @@ -3537,6 +3549,7 @@ twobyte_insn: break; case 5: /* not defined */ emulate_ud(ctxt); + rc = X86EMUL_PROPAGATE_FAULT; goto done; case 7: /* invlpg*/ emulate_invlpg(ctxt->vcpu, @@ -3567,6 +3580,7 @@ twobyte_insn: case 5 ... 7: case 9 ... 15: emulate_ud(ctxt); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } c->dst.val = ops->get_cr(c->modrm_reg, ctxt->vcpu); @@ -3575,6 +3589,7 @@ twobyte_insn: if ((ops->get_cr(4, ctxt->vcpu) & X86_CR4_DE) && (c->modrm_reg == 4 || c->modrm_reg == 5)) { emulate_ud(ctxt); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } ops->get_dr(c->modrm_reg, &c->dst.val, ctxt->vcpu); @@ -3582,6 +3597,7 @@ twobyte_insn: case 0x22: /* mov reg, cr */ if (ops->set_cr(c->modrm_reg, c->src.val, ctxt->vcpu)) { emulate_gp(ctxt, 0); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } c->dst.type = OP_NONE; @@ -3590,6 +3606,7 @@ twobyte_insn: if ((ops->get_cr(4, ctxt->vcpu) & X86_CR4_DE) && (c->modrm_reg == 4 || c->modrm_reg == 5)) { emulate_ud(ctxt); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } @@ -3598,6 +3615,7 @@ twobyte_insn: ~0ULL : ~0U), ctxt->vcpu) < 0) { /* #UD condition is already handled by the code above */ emulate_gp(ctxt, 0); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } @@ -3609,6 +3627,7 @@ twobyte_insn: | ((u64)c->regs[VCPU_REGS_RDX] << 32); if (ops->set_msr(ctxt->vcpu, c->regs[VCPU_REGS_RCX], msr_data)) { emulate_gp(ctxt, 0); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } rc = X86EMUL_CONTINUE; @@ -3617,6 +3636,7 @@ twobyte_insn: /* rdmsr */ if (ops->get_msr(ctxt->vcpu, c->regs[VCPU_REGS_RCX], &msr_data)) { emulate_gp(ctxt, 0); + rc = X86EMUL_PROPAGATE_FAULT; goto done; } else { c->regs[VCPU_REGS_RAX] = (u32)msr_data; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 651cf90..0c90832 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4254,12 +4254,13 @@ static void toggle_interruptibility(struct kvm_vcpu *vcpu, u32 mask) static void inject_emulated_exception(struct kvm_vcpu *vcpu) { struct x86_emulate_ctxt *ctxt = &vcpu->arch.emulate_ctxt; - if (ctxt->exception == PF_VECTOR) + if (ctxt->exception.vector == PF_VECTOR) kvm_propagate_fault(vcpu); - else if (ctxt->error_code_valid) - kvm_queue_exception_e(vcpu, ctxt->exception, ctxt->error_code); + else if (ctxt->exception.error_code_valid) + kvm_queue_exception_e(vcpu, ctxt->exception.vector, + ctxt->exception.error_code); else - kvm_queue_exception(vcpu, ctxt->exception); + kvm_queue_exception(vcpu, ctxt->exception.vector); } static void init_emulate_ctxt(struct kvm_vcpu *vcpu) @@ -4371,7 +4372,7 @@ int emulate_instruction(struct kvm_vcpu *vcpu, if (!(emulation_type & EMULTYPE_NO_DECODE)) { init_emulate_ctxt(vcpu); vcpu->arch.emulate_ctxt.interruptibility = 0; - vcpu->arch.emulate_ctxt.exception = -1; + vcpu->arch.emulate_ctxt.have_exception = false; vcpu->arch.emulate_ctxt.perm_ok = false; r = x86_decode_insn(&vcpu->arch.emulate_ctxt); @@ -4437,7 +4438,7 @@ restart: } done: - if (vcpu->arch.emulate_ctxt.exception >= 0) { + if (vcpu->arch.emulate_ctxt.have_exception) { inject_emulated_exception(vcpu); r = EMULATE_DONE; } else if (vcpu->arch.pio.count) { -- 2.7.4