KVM: x86 emulator: consolidate segment accessors
Instead of separate accessors for the segment selector and cached descriptor, use one accessor for both. This simplifies the code somewhat. Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Avi Kivity
Родитель
0a434bb2bf
Коммит
1aa366163b
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@ -164,15 +164,10 @@ struct x86_emulate_ops {
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int size, unsigned short port, const void *val,
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unsigned int count);
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bool (*get_cached_descriptor)(struct x86_emulate_ctxt *ctxt,
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struct desc_struct *desc, u32 *base3,
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int seg);
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void (*set_cached_descriptor)(struct x86_emulate_ctxt *ctxt,
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struct desc_struct *desc, u32 base3,
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int seg);
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u16 (*get_segment_selector)(struct x86_emulate_ctxt *ctxt, int seg);
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void (*set_segment_selector)(struct x86_emulate_ctxt *ctxt,
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u16 sel, int seg);
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bool (*get_segment)(struct x86_emulate_ctxt *ctxt, u16 *selector,
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struct desc_struct *desc, u32 *base3, int seg);
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void (*set_segment)(struct x86_emulate_ctxt *ctxt, u16 selector,
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struct desc_struct *desc, u32 base3, int seg);
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unsigned long (*get_cached_segment_base)(struct x86_emulate_ctxt *ctxt,
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int seg);
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void (*get_gdt)(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt);
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@ -553,6 +553,26 @@ static int emulate_nm(struct x86_emulate_ctxt *ctxt)
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return emulate_exception(ctxt, NM_VECTOR, 0, false);
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}
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static u16 get_segment_selector(struct x86_emulate_ctxt *ctxt, unsigned seg)
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{
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u16 selector;
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struct desc_struct desc;
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ctxt->ops->get_segment(ctxt, &selector, &desc, NULL, seg);
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return selector;
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}
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static void set_segment_selector(struct x86_emulate_ctxt *ctxt, u16 selector,
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unsigned seg)
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{
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u16 dummy;
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u32 base3;
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struct desc_struct desc;
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ctxt->ops->get_segment(ctxt, &dummy, &desc, &base3, seg);
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ctxt->ops->set_segment(ctxt, selector, &desc, base3, seg);
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}
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static int __linearize(struct x86_emulate_ctxt *ctxt,
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struct segmented_address addr,
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unsigned size, bool write, bool fetch,
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@ -563,6 +583,7 @@ static int __linearize(struct x86_emulate_ctxt *ctxt,
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bool usable;
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ulong la;
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u32 lim;
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u16 sel;
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unsigned cpl, rpl;
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la = seg_base(ctxt, ctxt->ops, addr.seg) + addr.ea;
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@ -574,8 +595,8 @@ static int __linearize(struct x86_emulate_ctxt *ctxt,
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return emulate_gp(ctxt, 0);
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break;
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default:
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usable = ctxt->ops->get_cached_descriptor(ctxt, &desc, NULL,
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addr.seg);
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usable = ctxt->ops->get_segment(ctxt, &sel, &desc, NULL,
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addr.seg);
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if (!usable)
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goto bad;
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/* code segment or read-only data segment */
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@ -598,7 +619,7 @@ static int __linearize(struct x86_emulate_ctxt *ctxt,
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goto bad;
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}
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cpl = ctxt->ops->cpl(ctxt);
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rpl = ctxt->ops->get_segment_selector(ctxt, addr.seg) & 3;
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rpl = sel & 3;
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cpl = max(cpl, rpl);
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if (!(desc.type & 8)) {
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/* data segment */
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@ -1142,9 +1163,10 @@ static void get_descriptor_table_ptr(struct x86_emulate_ctxt *ctxt,
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{
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if (selector & 1 << 2) {
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struct desc_struct desc;
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u16 sel;
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memset (dt, 0, sizeof *dt);
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if (!ops->get_cached_descriptor(ctxt, &desc, NULL,
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VCPU_SREG_LDTR))
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if (!ops->get_segment(ctxt, &sel, &desc, NULL, VCPU_SREG_LDTR))
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return;
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dt->size = desc_limit_scaled(&desc); /* what if limit > 65535? */
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@ -1305,8 +1327,7 @@ static int load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
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return ret;
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}
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load:
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ops->set_segment_selector(ctxt, selector, seg);
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ops->set_cached_descriptor(ctxt, &seg_desc, 0, seg);
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ops->set_segment(ctxt, selector, &seg_desc, 0, seg);
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return X86EMUL_CONTINUE;
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exception:
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emulate_exception(ctxt, err_vec, err_code, true);
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@ -1464,7 +1485,7 @@ static int emulate_push_sreg(struct x86_emulate_ctxt *ctxt,
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{
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struct decode_cache *c = &ctxt->decode;
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c->src.val = ops->get_segment_selector(ctxt, seg);
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c->src.val = get_segment_selector(ctxt, seg);
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return em_push(ctxt);
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}
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@ -1552,7 +1573,7 @@ int emulate_int_real(struct x86_emulate_ctxt *ctxt,
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ctxt->eflags &= ~(EFLG_IF | EFLG_TF | EFLG_AC);
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c->src.val = ops->get_segment_selector(ctxt, VCPU_SREG_CS);
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c->src.val = get_segment_selector(ctxt, VCPU_SREG_CS);
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rc = em_push(ctxt);
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if (rc != X86EMUL_CONTINUE)
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return rc;
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@ -1838,8 +1859,10 @@ setup_syscalls_segments(struct x86_emulate_ctxt *ctxt,
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struct x86_emulate_ops *ops, struct desc_struct *cs,
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struct desc_struct *ss)
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{
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u16 selector;
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memset(cs, 0, sizeof(struct desc_struct));
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ops->get_cached_descriptor(ctxt, cs, NULL, VCPU_SREG_CS);
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ops->get_segment(ctxt, &selector, cs, NULL, VCPU_SREG_CS);
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memset(ss, 0, sizeof(struct desc_struct));
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cs->l = 0; /* will be adjusted later */
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@ -1888,10 +1911,8 @@ emulate_syscall(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
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cs.d = 0;
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cs.l = 1;
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}
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ops->set_cached_descriptor(ctxt, &cs, 0, VCPU_SREG_CS);
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ops->set_segment_selector(ctxt, cs_sel, VCPU_SREG_CS);
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ops->set_cached_descriptor(ctxt, &ss, 0, VCPU_SREG_SS);
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ops->set_segment_selector(ctxt, ss_sel, VCPU_SREG_SS);
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ops->set_segment(ctxt, cs_sel, &cs, 0, VCPU_SREG_CS);
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ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS);
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c->regs[VCPU_REGS_RCX] = c->eip;
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if (efer & EFER_LMA) {
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@ -1961,10 +1982,8 @@ emulate_sysenter(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
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cs.l = 1;
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}
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ops->set_cached_descriptor(ctxt, &cs, 0, VCPU_SREG_CS);
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ops->set_segment_selector(ctxt, cs_sel, VCPU_SREG_CS);
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ops->set_cached_descriptor(ctxt, &ss, 0, VCPU_SREG_SS);
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ops->set_segment_selector(ctxt, ss_sel, VCPU_SREG_SS);
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ops->set_segment(ctxt, cs_sel, &cs, 0, VCPU_SREG_CS);
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ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS);
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ops->get_msr(ctxt, MSR_IA32_SYSENTER_EIP, &msr_data);
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c->eip = msr_data;
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@ -2018,10 +2037,8 @@ emulate_sysexit(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
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cs_sel |= SELECTOR_RPL_MASK;
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ss_sel |= SELECTOR_RPL_MASK;
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ops->set_cached_descriptor(ctxt, &cs, 0, VCPU_SREG_CS);
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ops->set_segment_selector(ctxt, cs_sel, VCPU_SREG_CS);
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ops->set_cached_descriptor(ctxt, &ss, 0, VCPU_SREG_SS);
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ops->set_segment_selector(ctxt, ss_sel, VCPU_SREG_SS);
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ops->set_segment(ctxt, cs_sel, &cs, 0, VCPU_SREG_CS);
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ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS);
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c->eip = c->regs[VCPU_REGS_RDX];
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c->regs[VCPU_REGS_RSP] = c->regs[VCPU_REGS_RCX];
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@ -2048,11 +2065,11 @@ static bool emulator_io_port_access_allowed(struct x86_emulate_ctxt *ctxt,
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struct desc_struct tr_seg;
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u32 base3;
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int r;
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u16 io_bitmap_ptr, perm, bit_idx = port & 0x7;
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u16 tr, io_bitmap_ptr, perm, bit_idx = port & 0x7;
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unsigned mask = (1 << len) - 1;
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unsigned long base;
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ops->get_cached_descriptor(ctxt, &tr_seg, &base3, VCPU_SREG_TR);
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ops->get_segment(ctxt, &tr, &tr_seg, &base3, VCPU_SREG_TR);
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if (!tr_seg.p)
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return false;
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if (desc_limit_scaled(&tr_seg) < 103)
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@ -2107,11 +2124,11 @@ static void save_state_to_tss16(struct x86_emulate_ctxt *ctxt,
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tss->si = c->regs[VCPU_REGS_RSI];
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tss->di = c->regs[VCPU_REGS_RDI];
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tss->es = ops->get_segment_selector(ctxt, VCPU_SREG_ES);
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tss->cs = ops->get_segment_selector(ctxt, VCPU_SREG_CS);
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tss->ss = ops->get_segment_selector(ctxt, VCPU_SREG_SS);
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tss->ds = ops->get_segment_selector(ctxt, VCPU_SREG_DS);
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tss->ldt = ops->get_segment_selector(ctxt, VCPU_SREG_LDTR);
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tss->es = get_segment_selector(ctxt, VCPU_SREG_ES);
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tss->cs = get_segment_selector(ctxt, VCPU_SREG_CS);
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tss->ss = get_segment_selector(ctxt, VCPU_SREG_SS);
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tss->ds = get_segment_selector(ctxt, VCPU_SREG_DS);
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tss->ldt = get_segment_selector(ctxt, VCPU_SREG_LDTR);
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}
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static int load_state_from_tss16(struct x86_emulate_ctxt *ctxt,
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@ -2136,11 +2153,11 @@ static int load_state_from_tss16(struct x86_emulate_ctxt *ctxt,
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* SDM says that segment selectors are loaded before segment
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* descriptors
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*/
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ops->set_segment_selector(ctxt, tss->ldt, VCPU_SREG_LDTR);
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ops->set_segment_selector(ctxt, tss->es, VCPU_SREG_ES);
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ops->set_segment_selector(ctxt, tss->cs, VCPU_SREG_CS);
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ops->set_segment_selector(ctxt, tss->ss, VCPU_SREG_SS);
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ops->set_segment_selector(ctxt, tss->ds, VCPU_SREG_DS);
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set_segment_selector(ctxt, tss->ldt, VCPU_SREG_LDTR);
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set_segment_selector(ctxt, tss->es, VCPU_SREG_ES);
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set_segment_selector(ctxt, tss->cs, VCPU_SREG_CS);
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set_segment_selector(ctxt, tss->ss, VCPU_SREG_SS);
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set_segment_selector(ctxt, tss->ds, VCPU_SREG_DS);
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/*
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* Now load segment descriptors. If fault happenes at this stage
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@ -2227,13 +2244,13 @@ static void save_state_to_tss32(struct x86_emulate_ctxt *ctxt,
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tss->esi = c->regs[VCPU_REGS_RSI];
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tss->edi = c->regs[VCPU_REGS_RDI];
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tss->es = ops->get_segment_selector(ctxt, VCPU_SREG_ES);
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tss->cs = ops->get_segment_selector(ctxt, VCPU_SREG_CS);
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tss->ss = ops->get_segment_selector(ctxt, VCPU_SREG_SS);
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tss->ds = ops->get_segment_selector(ctxt, VCPU_SREG_DS);
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tss->fs = ops->get_segment_selector(ctxt, VCPU_SREG_FS);
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tss->gs = ops->get_segment_selector(ctxt, VCPU_SREG_GS);
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tss->ldt_selector = ops->get_segment_selector(ctxt, VCPU_SREG_LDTR);
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tss->es = get_segment_selector(ctxt, VCPU_SREG_ES);
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tss->cs = get_segment_selector(ctxt, VCPU_SREG_CS);
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tss->ss = get_segment_selector(ctxt, VCPU_SREG_SS);
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tss->ds = get_segment_selector(ctxt, VCPU_SREG_DS);
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tss->fs = get_segment_selector(ctxt, VCPU_SREG_FS);
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tss->gs = get_segment_selector(ctxt, VCPU_SREG_GS);
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tss->ldt_selector = get_segment_selector(ctxt, VCPU_SREG_LDTR);
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}
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static int load_state_from_tss32(struct x86_emulate_ctxt *ctxt,
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@ -2260,13 +2277,13 @@ static int load_state_from_tss32(struct x86_emulate_ctxt *ctxt,
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* SDM says that segment selectors are loaded before segment
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* descriptors
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*/
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ops->set_segment_selector(ctxt, tss->ldt_selector, VCPU_SREG_LDTR);
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ops->set_segment_selector(ctxt, tss->es, VCPU_SREG_ES);
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ops->set_segment_selector(ctxt, tss->cs, VCPU_SREG_CS);
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ops->set_segment_selector(ctxt, tss->ss, VCPU_SREG_SS);
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ops->set_segment_selector(ctxt, tss->ds, VCPU_SREG_DS);
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ops->set_segment_selector(ctxt, tss->fs, VCPU_SREG_FS);
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ops->set_segment_selector(ctxt, tss->gs, VCPU_SREG_GS);
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set_segment_selector(ctxt, tss->ldt_selector, VCPU_SREG_LDTR);
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set_segment_selector(ctxt, tss->es, VCPU_SREG_ES);
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set_segment_selector(ctxt, tss->cs, VCPU_SREG_CS);
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set_segment_selector(ctxt, tss->ss, VCPU_SREG_SS);
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set_segment_selector(ctxt, tss->ds, VCPU_SREG_DS);
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set_segment_selector(ctxt, tss->fs, VCPU_SREG_FS);
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set_segment_selector(ctxt, tss->gs, VCPU_SREG_GS);
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/*
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* Now load segment descriptors. If fault happenes at this stage
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@ -2348,7 +2365,7 @@ static int emulator_do_task_switch(struct x86_emulate_ctxt *ctxt,
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{
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struct desc_struct curr_tss_desc, next_tss_desc;
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int ret;
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u16 old_tss_sel = ops->get_segment_selector(ctxt, VCPU_SREG_TR);
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u16 old_tss_sel = get_segment_selector(ctxt, VCPU_SREG_TR);
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ulong old_tss_base =
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ops->get_cached_segment_base(ctxt, VCPU_SREG_TR);
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u32 desc_limit;
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@ -2411,8 +2428,7 @@ static int emulator_do_task_switch(struct x86_emulate_ctxt *ctxt,
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}
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ops->set_cr(ctxt, 0, ops->get_cr(ctxt, 0) | X86_CR0_TS);
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ops->set_cached_descriptor(ctxt, &next_tss_desc, 0, VCPU_SREG_TR);
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ops->set_segment_selector(ctxt, tss_selector, VCPU_SREG_TR);
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ops->set_segment(ctxt, tss_selector, &next_tss_desc, 0, VCPU_SREG_TR);
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if (has_error_code) {
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struct decode_cache *c = &ctxt->decode;
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@ -2503,7 +2519,7 @@ static int em_call_far(struct x86_emulate_ctxt *ctxt)
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ulong old_eip;
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int rc;
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old_cs = ctxt->ops->get_segment_selector(ctxt, VCPU_SREG_CS);
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old_cs = get_segment_selector(ctxt, VCPU_SREG_CS);
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old_eip = c->eip;
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memcpy(&sel, c->src.valptr + c->op_bytes, 2);
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@ -3881,7 +3897,7 @@ special_insn:
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rc = emulate_ud(ctxt);
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goto done;
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}
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c->dst.val = ops->get_segment_selector(ctxt, c->modrm_reg);
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c->dst.val = get_segment_selector(ctxt, c->modrm_reg);
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break;
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case 0x8d: /* lea r16/r32, m */
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c->dst.val = c->src.addr.mem.ea;
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@ -4304,13 +4304,14 @@ static unsigned long emulator_get_cached_segment_base(
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return get_segment_base(emul_to_vcpu(ctxt), seg);
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}
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static bool emulator_get_cached_descriptor(struct x86_emulate_ctxt *ctxt,
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struct desc_struct *desc, u32 *base3,
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int seg)
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static bool emulator_get_segment(struct x86_emulate_ctxt *ctxt, u16 *selector,
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struct desc_struct *desc, u32 *base3,
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int seg)
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{
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struct kvm_segment var;
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kvm_get_segment(emul_to_vcpu(ctxt), &var, seg);
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*selector = var.selector;
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if (var.unusable)
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return false;
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@ -4335,16 +4336,14 @@ static bool emulator_get_cached_descriptor(struct x86_emulate_ctxt *ctxt,
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return true;
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}
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static void emulator_set_cached_descriptor(struct x86_emulate_ctxt *ctxt,
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struct desc_struct *desc, u32 base3,
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int seg)
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static void emulator_set_segment(struct x86_emulate_ctxt *ctxt, u16 selector,
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struct desc_struct *desc, u32 base3,
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int seg)
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{
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struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
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struct kvm_segment var;
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/* needed to preserve selector */
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kvm_get_segment(vcpu, &var, seg);
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var.selector = selector;
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var.base = get_desc_base(desc);
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#ifdef CONFIG_X86_64
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var.base |= ((u64)base3) << 32;
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@ -4368,24 +4367,6 @@ static void emulator_set_cached_descriptor(struct x86_emulate_ctxt *ctxt,
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return;
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}
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static u16 emulator_get_segment_selector(struct x86_emulate_ctxt *ctxt, int seg)
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{
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struct kvm_segment kvm_seg;
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kvm_get_segment(emul_to_vcpu(ctxt), &kvm_seg, seg);
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return kvm_seg.selector;
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}
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||||
|
||||
static void emulator_set_segment_selector(struct x86_emulate_ctxt *ctxt,
|
||||
u16 sel, int seg)
|
||||
{
|
||||
struct kvm_segment kvm_seg;
|
||||
|
||||
kvm_get_segment(emul_to_vcpu(ctxt), &kvm_seg, seg);
|
||||
kvm_seg.selector = sel;
|
||||
kvm_set_segment(emul_to_vcpu(ctxt), &kvm_seg, seg);
|
||||
}
|
||||
|
||||
static int emulator_get_msr(struct x86_emulate_ctxt *ctxt,
|
||||
u32 msr_index, u64 *pdata)
|
||||
{
|
||||
|
|
@ -4436,10 +4417,8 @@ static struct x86_emulate_ops emulate_ops = {
|
|||
.invlpg = emulator_invlpg,
|
||||
.pio_in_emulated = emulator_pio_in_emulated,
|
||||
.pio_out_emulated = emulator_pio_out_emulated,
|
||||
.get_cached_descriptor = emulator_get_cached_descriptor,
|
||||
.set_cached_descriptor = emulator_set_cached_descriptor,
|
||||
.get_segment_selector = emulator_get_segment_selector,
|
||||
.set_segment_selector = emulator_set_segment_selector,
|
||||
.get_segment = emulator_get_segment,
|
||||
.set_segment = emulator_set_segment,
|
||||
.get_cached_segment_base = emulator_get_cached_segment_base,
|
||||
.get_gdt = emulator_get_gdt,
|
||||
.get_idt = emulator_get_idt,
|
||||
|
|
|
|||
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Ссылка в новой задаче