From bcc55cba9f1fcda68412c8c3d8579c56d90b16f2 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Mon, 22 Nov 2010 17:53:22 +0200 Subject: [PATCH] KVM: x86 emulator: make emulator memory callbacks return full exception This way, they can return #GP, not just #PF. Signed-off-by: Avi Kivity Signed-off-by: Marcelo Tosatti --- arch/x86/include/asm/kvm_emulate.h | 15 +++-- arch/x86/kvm/emulate.c | 89 +++++++++++------------------- arch/x86/kvm/x86.c | 76 ++++++++++++++----------- 3 files changed, 84 insertions(+), 96 deletions(-) diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h index b7c11270ae8f..87d017e276f4 100644 --- a/arch/x86/include/asm/kvm_emulate.h +++ b/arch/x86/include/asm/kvm_emulate.h @@ -70,7 +70,8 @@ struct x86_emulate_ops { * @bytes: [IN ] Number of bytes to read from memory. */ int (*read_std)(unsigned long addr, void *val, - unsigned int bytes, struct kvm_vcpu *vcpu, u32 *error); + unsigned int bytes, struct kvm_vcpu *vcpu, + struct x86_exception *fault); /* * write_std: Write bytes of standard (non-emulated/special) memory. @@ -80,7 +81,8 @@ struct x86_emulate_ops { * @bytes: [IN ] Number of bytes to write to memory. */ int (*write_std)(unsigned long addr, void *val, - unsigned int bytes, struct kvm_vcpu *vcpu, u32 *error); + unsigned int bytes, struct kvm_vcpu *vcpu, + struct x86_exception *fault); /* * fetch: Read bytes of standard (non-emulated/special) memory. * Used for instruction fetch. @@ -89,7 +91,8 @@ struct x86_emulate_ops { * @bytes: [IN ] Number of bytes to read from memory. */ int (*fetch)(unsigned long addr, void *val, - unsigned int bytes, struct kvm_vcpu *vcpu, u32 *error); + unsigned int bytes, struct kvm_vcpu *vcpu, + struct x86_exception *fault); /* * read_emulated: Read bytes from emulated/special memory area. @@ -100,7 +103,7 @@ struct x86_emulate_ops { int (*read_emulated)(unsigned long addr, void *val, unsigned int bytes, - unsigned int *error, + struct x86_exception *fault, struct kvm_vcpu *vcpu); /* @@ -113,7 +116,7 @@ struct x86_emulate_ops { int (*write_emulated)(unsigned long addr, const void *val, unsigned int bytes, - unsigned int *error, + struct x86_exception *fault, struct kvm_vcpu *vcpu); /* @@ -128,7 +131,7 @@ struct x86_emulate_ops { const void *old, const void *new, unsigned int bytes, - unsigned int *error, + struct x86_exception *fault, struct kvm_vcpu *vcpu); int (*pio_in_emulated)(int size, unsigned short port, void *val, diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 18596e6649aa..16ed6c178bb2 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -512,7 +512,7 @@ static int do_fetch_insn_byte(struct x86_emulate_ctxt *ctxt, 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); + size, ctxt->vcpu, &ctxt->exception); if (rc != X86EMUL_CONTINUE) return rc; fc->end += size; @@ -565,12 +565,12 @@ static int read_descriptor(struct x86_emulate_ctxt *ctxt, op_bytes = 3; *address = 0; rc = ops->read_std(linear(ctxt, addr), (unsigned long *)size, 2, - ctxt->vcpu, NULL); + ctxt->vcpu, &ctxt->exception); if (rc != X86EMUL_CONTINUE) return rc; addr.ea += 2; rc = ops->read_std(linear(ctxt, addr), address, op_bytes, - ctxt->vcpu, NULL); + ctxt->vcpu, &ctxt->exception); return rc; } @@ -816,7 +816,6 @@ static int read_emulated(struct x86_emulate_ctxt *ctxt, { int rc; struct read_cache *mc = &ctxt->decode.mem_read; - u32 err; while (size) { int n = min(size, 8u); @@ -824,10 +823,8 @@ static int read_emulated(struct x86_emulate_ctxt *ctxt, if (mc->pos < mc->end) goto read_cached; - rc = ops->read_emulated(addr, mc->data + mc->end, n, &err, - ctxt->vcpu); - if (rc == X86EMUL_PROPAGATE_FAULT) - emulate_pf(ctxt); + rc = ops->read_emulated(addr, mc->data + mc->end, n, + &ctxt->exception, ctxt->vcpu); if (rc != X86EMUL_CONTINUE) return rc; mc->end += n; @@ -902,7 +899,6 @@ static int read_segment_descriptor(struct x86_emulate_ctxt *ctxt, struct desc_ptr dt; u16 index = selector >> 3; int ret; - u32 err; ulong addr; get_descriptor_table_ptr(ctxt, ops, selector, &dt); @@ -912,9 +908,8 @@ static int read_segment_descriptor(struct x86_emulate_ctxt *ctxt, return X86EMUL_PROPAGATE_FAULT; } addr = dt.address + index * 8; - ret = ops->read_std(addr, desc, sizeof *desc, ctxt->vcpu, &err); - if (ret == X86EMUL_PROPAGATE_FAULT) - emulate_pf(ctxt); + ret = ops->read_std(addr, desc, sizeof *desc, ctxt->vcpu, + &ctxt->exception); return ret; } @@ -926,7 +921,6 @@ static int write_segment_descriptor(struct x86_emulate_ctxt *ctxt, { struct desc_ptr dt; u16 index = selector >> 3; - u32 err; ulong addr; int ret; @@ -938,9 +932,8 @@ static int write_segment_descriptor(struct x86_emulate_ctxt *ctxt, } addr = dt.address + index * 8; - ret = ops->write_std(addr, desc, sizeof *desc, ctxt->vcpu, &err); - if (ret == X86EMUL_PROPAGATE_FAULT) - emulate_pf(ctxt); + ret = ops->write_std(addr, desc, sizeof *desc, ctxt->vcpu, + &ctxt->exception); return ret; } @@ -1087,7 +1080,6 @@ static inline int writeback(struct x86_emulate_ctxt *ctxt, { int rc; struct decode_cache *c = &ctxt->decode; - u32 err; switch (c->dst.type) { case OP_REG: @@ -1100,17 +1092,15 @@ static inline int writeback(struct x86_emulate_ctxt *ctxt, &c->dst.orig_val, &c->dst.val, c->dst.bytes, - &err, + &ctxt->exception, ctxt->vcpu); else rc = ops->write_emulated( linear(ctxt, c->dst.addr.mem), &c->dst.val, c->dst.bytes, - &err, + &ctxt->exception, ctxt->vcpu); - if (rc == X86EMUL_PROPAGATE_FAULT) - emulate_pf(ctxt); if (rc != X86EMUL_CONTINUE) return rc; break; @@ -1283,7 +1273,6 @@ int emulate_int_real(struct x86_emulate_ctxt *ctxt, gva_t cs_addr; gva_t eip_addr; u16 cs, eip; - u32 err; /* TODO: Add limit checks */ c->src.val = ctxt->eflags; @@ -1313,11 +1302,11 @@ int emulate_int_real(struct x86_emulate_ctxt *ctxt, eip_addr = dt.address + (irq << 2); cs_addr = dt.address + (irq << 2) + 2; - rc = ops->read_std(cs_addr, &cs, 2, ctxt->vcpu, &err); + rc = ops->read_std(cs_addr, &cs, 2, ctxt->vcpu, &ctxt->exception); if (rc != X86EMUL_CONTINUE) return rc; - rc = ops->read_std(eip_addr, &eip, 2, ctxt->vcpu, &err); + rc = ops->read_std(eip_addr, &eip, 2, ctxt->vcpu, &ctxt->exception); if (rc != X86EMUL_CONTINUE) return rc; @@ -1930,33 +1919,27 @@ static int task_switch_16(struct x86_emulate_ctxt *ctxt, { struct tss_segment_16 tss_seg; int ret; - u32 err, new_tss_base = get_desc_base(new_desc); + u32 new_tss_base = get_desc_base(new_desc); ret = ops->read_std(old_tss_base, &tss_seg, sizeof tss_seg, ctxt->vcpu, - &err); - if (ret == X86EMUL_PROPAGATE_FAULT) { + &ctxt->exception); + if (ret == X86EMUL_PROPAGATE_FAULT) /* FIXME: need to provide precise fault address */ - emulate_pf(ctxt); return ret; - } save_state_to_tss16(ctxt, ops, &tss_seg); ret = ops->write_std(old_tss_base, &tss_seg, sizeof tss_seg, ctxt->vcpu, - &err); - if (ret == X86EMUL_PROPAGATE_FAULT) { + &ctxt->exception); + if (ret == X86EMUL_PROPAGATE_FAULT) /* FIXME: need to provide precise fault address */ - emulate_pf(ctxt); return ret; - } ret = ops->read_std(new_tss_base, &tss_seg, sizeof tss_seg, ctxt->vcpu, - &err); - if (ret == X86EMUL_PROPAGATE_FAULT) { + &ctxt->exception); + if (ret == X86EMUL_PROPAGATE_FAULT) /* FIXME: need to provide precise fault address */ - emulate_pf(ctxt); return ret; - } if (old_tss_sel != 0xffff) { tss_seg.prev_task_link = old_tss_sel; @@ -1964,12 +1947,10 @@ static int task_switch_16(struct x86_emulate_ctxt *ctxt, ret = ops->write_std(new_tss_base, &tss_seg.prev_task_link, sizeof tss_seg.prev_task_link, - ctxt->vcpu, &err); - if (ret == X86EMUL_PROPAGATE_FAULT) { + ctxt->vcpu, &ctxt->exception); + if (ret == X86EMUL_PROPAGATE_FAULT) /* FIXME: need to provide precise fault address */ - emulate_pf(ctxt); return ret; - } } return load_state_from_tss16(ctxt, ops, &tss_seg); @@ -2072,33 +2053,27 @@ static int task_switch_32(struct x86_emulate_ctxt *ctxt, { struct tss_segment_32 tss_seg; int ret; - u32 err, new_tss_base = get_desc_base(new_desc); + u32 new_tss_base = get_desc_base(new_desc); ret = ops->read_std(old_tss_base, &tss_seg, sizeof tss_seg, ctxt->vcpu, - &err); - if (ret == X86EMUL_PROPAGATE_FAULT) { + &ctxt->exception); + if (ret == X86EMUL_PROPAGATE_FAULT) /* FIXME: need to provide precise fault address */ - emulate_pf(ctxt); return ret; - } save_state_to_tss32(ctxt, ops, &tss_seg); ret = ops->write_std(old_tss_base, &tss_seg, sizeof tss_seg, ctxt->vcpu, - &err); - if (ret == X86EMUL_PROPAGATE_FAULT) { + &ctxt->exception); + if (ret == X86EMUL_PROPAGATE_FAULT) /* FIXME: need to provide precise fault address */ - emulate_pf(ctxt); return ret; - } ret = ops->read_std(new_tss_base, &tss_seg, sizeof tss_seg, ctxt->vcpu, - &err); - if (ret == X86EMUL_PROPAGATE_FAULT) { + &ctxt->exception); + if (ret == X86EMUL_PROPAGATE_FAULT) /* FIXME: need to provide precise fault address */ - emulate_pf(ctxt); return ret; - } if (old_tss_sel != 0xffff) { tss_seg.prev_task_link = old_tss_sel; @@ -2106,12 +2081,10 @@ static int task_switch_32(struct x86_emulate_ctxt *ctxt, ret = ops->write_std(new_tss_base, &tss_seg.prev_task_link, sizeof tss_seg.prev_task_link, - ctxt->vcpu, &err); - if (ret == X86EMUL_PROPAGATE_FAULT) { + ctxt->vcpu, &ctxt->exception); + if (ret == X86EMUL_PROPAGATE_FAULT) /* FIXME: need to provide precise fault address */ - emulate_pf(ctxt); return ret; - } } return load_state_from_tss32(ctxt, ops, &tss_seg); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 0c908321e900..8311ed909c49 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3642,24 +3642,31 @@ gpa_t kvm_mmu_gva_to_gpa_system(struct kvm_vcpu *vcpu, gva_t gva, u32 *error) return vcpu->arch.walk_mmu->gva_to_gpa(vcpu, gva, 0, error); } +static int make_page_fault(struct x86_exception *exception, u32 error) +{ + exception->vector = PF_VECTOR; + exception->error_code_valid = true; + exception->error_code = error; + return X86EMUL_PROPAGATE_FAULT; +} + static int kvm_read_guest_virt_helper(gva_t addr, void *val, unsigned int bytes, struct kvm_vcpu *vcpu, u32 access, - u32 *error) + struct x86_exception *exception) { void *data = val; int r = X86EMUL_CONTINUE; + u32 error; while (bytes) { gpa_t gpa = vcpu->arch.walk_mmu->gva_to_gpa(vcpu, addr, access, - error); + &error); unsigned offset = addr & (PAGE_SIZE-1); unsigned toread = min(bytes, (unsigned)PAGE_SIZE - offset); int ret; - if (gpa == UNMAPPED_GVA) { - r = X86EMUL_PROPAGATE_FAULT; - goto out; - } + if (gpa == UNMAPPED_GVA) + return make_page_fault(exception, error); ret = kvm_read_guest(vcpu->kvm, gpa, data, toread); if (ret < 0) { r = X86EMUL_IO_NEEDED; @@ -3676,47 +3683,50 @@ out: /* used for instruction fetching */ static int kvm_fetch_guest_virt(gva_t addr, void *val, unsigned int bytes, - struct kvm_vcpu *vcpu, u32 *error) + struct kvm_vcpu *vcpu, + struct x86_exception *exception) { u32 access = (kvm_x86_ops->get_cpl(vcpu) == 3) ? PFERR_USER_MASK : 0; return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, - access | PFERR_FETCH_MASK, error); + access | PFERR_FETCH_MASK, + exception); } static int kvm_read_guest_virt(gva_t addr, void *val, unsigned int bytes, - struct kvm_vcpu *vcpu, u32 *error) + struct kvm_vcpu *vcpu, + struct x86_exception *exception) { u32 access = (kvm_x86_ops->get_cpl(vcpu) == 3) ? PFERR_USER_MASK : 0; return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, access, - error); + exception); } static int kvm_read_guest_virt_system(gva_t addr, void *val, unsigned int bytes, - struct kvm_vcpu *vcpu, u32 *error) + struct kvm_vcpu *vcpu, + struct x86_exception *exception) { - return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, 0, error); + return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, 0, exception); } static int kvm_write_guest_virt_system(gva_t addr, void *val, unsigned int bytes, struct kvm_vcpu *vcpu, - u32 *error) + struct x86_exception *exception) { void *data = val; int r = X86EMUL_CONTINUE; + u32 error; while (bytes) { gpa_t gpa = vcpu->arch.walk_mmu->gva_to_gpa(vcpu, addr, PFERR_WRITE_MASK, - error); + &error); unsigned offset = addr & (PAGE_SIZE-1); unsigned towrite = min(bytes, (unsigned)PAGE_SIZE - offset); int ret; - if (gpa == UNMAPPED_GVA) { - r = X86EMUL_PROPAGATE_FAULT; - goto out; - } + if (gpa == UNMAPPED_GVA) + return make_page_fault(exception, error); ret = kvm_write_guest(vcpu->kvm, gpa, data, towrite); if (ret < 0) { r = X86EMUL_IO_NEEDED; @@ -3734,10 +3744,11 @@ out: static int emulator_read_emulated(unsigned long addr, void *val, unsigned int bytes, - unsigned int *error_code, + struct x86_exception *exception, struct kvm_vcpu *vcpu) { gpa_t gpa; + u32 error_code; if (vcpu->mmio_read_completed) { memcpy(val, vcpu->mmio_data, bytes); @@ -3747,17 +3758,17 @@ static int emulator_read_emulated(unsigned long addr, return X86EMUL_CONTINUE; } - gpa = kvm_mmu_gva_to_gpa_read(vcpu, addr, error_code); + gpa = kvm_mmu_gva_to_gpa_read(vcpu, addr, &error_code); if (gpa == UNMAPPED_GVA) - return X86EMUL_PROPAGATE_FAULT; + return make_page_fault(exception, error_code); /* For APIC access vmexit */ if ((gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE) goto mmio; - if (kvm_read_guest_virt(addr, val, bytes, vcpu, NULL) - == X86EMUL_CONTINUE) + if (kvm_read_guest_virt(addr, val, bytes, vcpu, exception) + == X86EMUL_CONTINUE) return X86EMUL_CONTINUE; mmio: @@ -3781,7 +3792,7 @@ mmio: } int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa, - const void *val, int bytes) + const void *val, int bytes) { int ret; @@ -3795,15 +3806,16 @@ int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa, static int emulator_write_emulated_onepage(unsigned long addr, const void *val, unsigned int bytes, - unsigned int *error_code, + struct x86_exception *exception, struct kvm_vcpu *vcpu) { gpa_t gpa; + u32 error_code; - gpa = kvm_mmu_gva_to_gpa_write(vcpu, addr, error_code); + gpa = kvm_mmu_gva_to_gpa_write(vcpu, addr, &error_code); if (gpa == UNMAPPED_GVA) - return X86EMUL_PROPAGATE_FAULT; + return make_page_fault(exception, error_code); /* For APIC access vmexit */ if ((gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE) @@ -3833,7 +3845,7 @@ mmio: int emulator_write_emulated(unsigned long addr, const void *val, unsigned int bytes, - unsigned int *error_code, + struct x86_exception *exception, struct kvm_vcpu *vcpu) { /* Crossing a page boundary? */ @@ -3841,7 +3853,7 @@ int emulator_write_emulated(unsigned long addr, int rc, now; now = -addr & ~PAGE_MASK; - rc = emulator_write_emulated_onepage(addr, val, now, error_code, + rc = emulator_write_emulated_onepage(addr, val, now, exception, vcpu); if (rc != X86EMUL_CONTINUE) return rc; @@ -3849,7 +3861,7 @@ int emulator_write_emulated(unsigned long addr, val += now; bytes -= now; } - return emulator_write_emulated_onepage(addr, val, bytes, error_code, + return emulator_write_emulated_onepage(addr, val, bytes, exception, vcpu); } @@ -3867,7 +3879,7 @@ static int emulator_cmpxchg_emulated(unsigned long addr, const void *old, const void *new, unsigned int bytes, - unsigned int *error_code, + struct x86_exception *exception, struct kvm_vcpu *vcpu) { gpa_t gpa; @@ -3925,7 +3937,7 @@ static int emulator_cmpxchg_emulated(unsigned long addr, emul_write: printk_once(KERN_WARNING "kvm: emulating exchange as write\n"); - return emulator_write_emulated(addr, new, bytes, error_code, vcpu); + return emulator_write_emulated(addr, new, bytes, exception, vcpu); } static int kernel_pio(struct kvm_vcpu *vcpu, void *pd) -- 2.30.2