xref: /openbmc/qemu/target/i386/tcg/seg_helper.c (revision b2580720)
1 /*
2  *  x86 segmentation related helpers:
3  *  TSS, interrupts, system calls, jumps and call/task gates, descriptors
4  *
5  *  Copyright (c) 2003 Fabrice Bellard
6  *
7  * This library is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * This library is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
19  */
20 
21 #include "qemu/osdep.h"
22 #include "cpu.h"
23 #include "qemu/log.h"
24 #include "exec/helper-proto.h"
25 #include "exec/exec-all.h"
26 #include "exec/cpu_ldst.h"
27 #include "exec/log.h"
28 #include "helper-tcg.h"
29 #include "seg_helper.h"
30 
31 int get_pg_mode(CPUX86State *env)
32 {
33     int pg_mode = 0;
34     if (!(env->cr[0] & CR0_PG_MASK)) {
35         return 0;
36     }
37     if (env->cr[0] & CR0_WP_MASK) {
38         pg_mode |= PG_MODE_WP;
39     }
40     if (env->cr[4] & CR4_PAE_MASK) {
41         pg_mode |= PG_MODE_PAE;
42         if (env->efer & MSR_EFER_NXE) {
43             pg_mode |= PG_MODE_NXE;
44         }
45     }
46     if (env->cr[4] & CR4_PSE_MASK) {
47         pg_mode |= PG_MODE_PSE;
48     }
49     if (env->cr[4] & CR4_SMEP_MASK) {
50         pg_mode |= PG_MODE_SMEP;
51     }
52     if (env->hflags & HF_LMA_MASK) {
53         pg_mode |= PG_MODE_LMA;
54         if (env->cr[4] & CR4_PKE_MASK) {
55             pg_mode |= PG_MODE_PKE;
56         }
57         if (env->cr[4] & CR4_PKS_MASK) {
58             pg_mode |= PG_MODE_PKS;
59         }
60         if (env->cr[4] & CR4_LA57_MASK) {
61             pg_mode |= PG_MODE_LA57;
62         }
63     }
64     return pg_mode;
65 }
66 
67 /* return non zero if error */
68 static inline int load_segment_ra(CPUX86State *env, uint32_t *e1_ptr,
69                                uint32_t *e2_ptr, int selector,
70                                uintptr_t retaddr)
71 {
72     SegmentCache *dt;
73     int index;
74     target_ulong ptr;
75 
76     if (selector & 0x4) {
77         dt = &env->ldt;
78     } else {
79         dt = &env->gdt;
80     }
81     index = selector & ~7;
82     if ((index + 7) > dt->limit) {
83         return -1;
84     }
85     ptr = dt->base + index;
86     *e1_ptr = cpu_ldl_kernel_ra(env, ptr, retaddr);
87     *e2_ptr = cpu_ldl_kernel_ra(env, ptr + 4, retaddr);
88     return 0;
89 }
90 
91 static inline int load_segment(CPUX86State *env, uint32_t *e1_ptr,
92                                uint32_t *e2_ptr, int selector)
93 {
94     return load_segment_ra(env, e1_ptr, e2_ptr, selector, 0);
95 }
96 
97 static inline unsigned int get_seg_limit(uint32_t e1, uint32_t e2)
98 {
99     unsigned int limit;
100 
101     limit = (e1 & 0xffff) | (e2 & 0x000f0000);
102     if (e2 & DESC_G_MASK) {
103         limit = (limit << 12) | 0xfff;
104     }
105     return limit;
106 }
107 
108 static inline uint32_t get_seg_base(uint32_t e1, uint32_t e2)
109 {
110     return (e1 >> 16) | ((e2 & 0xff) << 16) | (e2 & 0xff000000);
111 }
112 
113 static inline void load_seg_cache_raw_dt(SegmentCache *sc, uint32_t e1,
114                                          uint32_t e2)
115 {
116     sc->base = get_seg_base(e1, e2);
117     sc->limit = get_seg_limit(e1, e2);
118     sc->flags = e2;
119 }
120 
121 /* init the segment cache in vm86 mode. */
122 static inline void load_seg_vm(CPUX86State *env, int seg, int selector)
123 {
124     selector &= 0xffff;
125 
126     cpu_x86_load_seg_cache(env, seg, selector, (selector << 4), 0xffff,
127                            DESC_P_MASK | DESC_S_MASK | DESC_W_MASK |
128                            DESC_A_MASK | (3 << DESC_DPL_SHIFT));
129 }
130 
131 static inline void get_ss_esp_from_tss(CPUX86State *env, uint32_t *ss_ptr,
132                                        uint32_t *esp_ptr, int dpl,
133                                        uintptr_t retaddr)
134 {
135     X86CPU *cpu = env_archcpu(env);
136     int type, index, shift;
137 
138 #if 0
139     {
140         int i;
141         printf("TR: base=%p limit=%x\n", env->tr.base, env->tr.limit);
142         for (i = 0; i < env->tr.limit; i++) {
143             printf("%02x ", env->tr.base[i]);
144             if ((i & 7) == 7) {
145                 printf("\n");
146             }
147         }
148         printf("\n");
149     }
150 #endif
151 
152     if (!(env->tr.flags & DESC_P_MASK)) {
153         cpu_abort(CPU(cpu), "invalid tss");
154     }
155     type = (env->tr.flags >> DESC_TYPE_SHIFT) & 0xf;
156     if ((type & 7) != 1) {
157         cpu_abort(CPU(cpu), "invalid tss type");
158     }
159     shift = type >> 3;
160     index = (dpl * 4 + 2) << shift;
161     if (index + (4 << shift) - 1 > env->tr.limit) {
162         raise_exception_err_ra(env, EXCP0A_TSS, env->tr.selector & 0xfffc, retaddr);
163     }
164     if (shift == 0) {
165         *esp_ptr = cpu_lduw_kernel_ra(env, env->tr.base + index, retaddr);
166         *ss_ptr = cpu_lduw_kernel_ra(env, env->tr.base + index + 2, retaddr);
167     } else {
168         *esp_ptr = cpu_ldl_kernel_ra(env, env->tr.base + index, retaddr);
169         *ss_ptr = cpu_lduw_kernel_ra(env, env->tr.base + index + 4, retaddr);
170     }
171 }
172 
173 static void tss_load_seg(CPUX86State *env, X86Seg seg_reg, int selector,
174                          int cpl, uintptr_t retaddr)
175 {
176     uint32_t e1, e2;
177     int rpl, dpl;
178 
179     if ((selector & 0xfffc) != 0) {
180         if (load_segment_ra(env, &e1, &e2, selector, retaddr) != 0) {
181             raise_exception_err_ra(env, EXCP0A_TSS, selector & 0xfffc, retaddr);
182         }
183         if (!(e2 & DESC_S_MASK)) {
184             raise_exception_err_ra(env, EXCP0A_TSS, selector & 0xfffc, retaddr);
185         }
186         rpl = selector & 3;
187         dpl = (e2 >> DESC_DPL_SHIFT) & 3;
188         if (seg_reg == R_CS) {
189             if (!(e2 & DESC_CS_MASK)) {
190                 raise_exception_err_ra(env, EXCP0A_TSS, selector & 0xfffc, retaddr);
191             }
192             if (dpl != rpl) {
193                 raise_exception_err_ra(env, EXCP0A_TSS, selector & 0xfffc, retaddr);
194             }
195         } else if (seg_reg == R_SS) {
196             /* SS must be writable data */
197             if ((e2 & DESC_CS_MASK) || !(e2 & DESC_W_MASK)) {
198                 raise_exception_err_ra(env, EXCP0A_TSS, selector & 0xfffc, retaddr);
199             }
200             if (dpl != cpl || dpl != rpl) {
201                 raise_exception_err_ra(env, EXCP0A_TSS, selector & 0xfffc, retaddr);
202             }
203         } else {
204             /* not readable code */
205             if ((e2 & DESC_CS_MASK) && !(e2 & DESC_R_MASK)) {
206                 raise_exception_err_ra(env, EXCP0A_TSS, selector & 0xfffc, retaddr);
207             }
208             /* if data or non conforming code, checks the rights */
209             if (((e2 >> DESC_TYPE_SHIFT) & 0xf) < 12) {
210                 if (dpl < cpl || dpl < rpl) {
211                     raise_exception_err_ra(env, EXCP0A_TSS, selector & 0xfffc, retaddr);
212                 }
213             }
214         }
215         if (!(e2 & DESC_P_MASK)) {
216             raise_exception_err_ra(env, EXCP0B_NOSEG, selector & 0xfffc, retaddr);
217         }
218         cpu_x86_load_seg_cache(env, seg_reg, selector,
219                                get_seg_base(e1, e2),
220                                get_seg_limit(e1, e2),
221                                e2);
222     } else {
223         if (seg_reg == R_SS || seg_reg == R_CS) {
224             raise_exception_err_ra(env, EXCP0A_TSS, selector & 0xfffc, retaddr);
225         }
226     }
227 }
228 
229 static void tss_set_busy(CPUX86State *env, int tss_selector, bool value,
230                          uintptr_t retaddr)
231 {
232     target_ulong ptr = env->gdt.base + (tss_selector & ~7);
233     uint32_t e2 = cpu_ldl_kernel_ra(env, ptr + 4, retaddr);
234 
235     if (value) {
236         e2 |= DESC_TSS_BUSY_MASK;
237     } else {
238         e2 &= ~DESC_TSS_BUSY_MASK;
239     }
240 
241     cpu_stl_kernel_ra(env, ptr + 4, e2, retaddr);
242 }
243 
244 #define SWITCH_TSS_JMP  0
245 #define SWITCH_TSS_IRET 1
246 #define SWITCH_TSS_CALL 2
247 
248 /* return 0 if switching to a 16-bit selector */
249 static int switch_tss_ra(CPUX86State *env, int tss_selector,
250                          uint32_t e1, uint32_t e2, int source,
251                          uint32_t next_eip, uintptr_t retaddr)
252 {
253     int tss_limit, tss_limit_max, type, old_tss_limit_max, old_type, v1, v2, i;
254     target_ulong tss_base;
255     uint32_t new_regs[8], new_segs[6];
256     uint32_t new_eflags, new_eip, new_cr3, new_ldt, new_trap;
257     uint32_t old_eflags, eflags_mask;
258     SegmentCache *dt;
259     int index;
260     target_ulong ptr;
261 
262     type = (e2 >> DESC_TYPE_SHIFT) & 0xf;
263     LOG_PCALL("switch_tss: sel=0x%04x type=%d src=%d\n", tss_selector, type,
264               source);
265 
266     /* if task gate, we read the TSS segment and we load it */
267     if (type == 5) {
268         if (!(e2 & DESC_P_MASK)) {
269             raise_exception_err_ra(env, EXCP0B_NOSEG, tss_selector & 0xfffc, retaddr);
270         }
271         tss_selector = e1 >> 16;
272         if (tss_selector & 4) {
273             raise_exception_err_ra(env, EXCP0A_TSS, tss_selector & 0xfffc, retaddr);
274         }
275         if (load_segment_ra(env, &e1, &e2, tss_selector, retaddr) != 0) {
276             raise_exception_err_ra(env, EXCP0D_GPF, tss_selector & 0xfffc, retaddr);
277         }
278         if (e2 & DESC_S_MASK) {
279             raise_exception_err_ra(env, EXCP0D_GPF, tss_selector & 0xfffc, retaddr);
280         }
281         type = (e2 >> DESC_TYPE_SHIFT) & 0xf;
282         if ((type & 7) != 1) {
283             raise_exception_err_ra(env, EXCP0D_GPF, tss_selector & 0xfffc, retaddr);
284         }
285     }
286 
287     if (!(e2 & DESC_P_MASK)) {
288         raise_exception_err_ra(env, EXCP0B_NOSEG, tss_selector & 0xfffc, retaddr);
289     }
290 
291     if (type & 8) {
292         tss_limit_max = 103;
293     } else {
294         tss_limit_max = 43;
295     }
296     tss_limit = get_seg_limit(e1, e2);
297     tss_base = get_seg_base(e1, e2);
298     if ((tss_selector & 4) != 0 ||
299         tss_limit < tss_limit_max) {
300         raise_exception_err_ra(env, EXCP0A_TSS, tss_selector & 0xfffc, retaddr);
301     }
302     old_type = (env->tr.flags >> DESC_TYPE_SHIFT) & 0xf;
303     if (old_type & 8) {
304         old_tss_limit_max = 103;
305     } else {
306         old_tss_limit_max = 43;
307     }
308 
309     /* read all the registers from the new TSS */
310     if (type & 8) {
311         /* 32 bit */
312         new_cr3 = cpu_ldl_kernel_ra(env, tss_base + 0x1c, retaddr);
313         new_eip = cpu_ldl_kernel_ra(env, tss_base + 0x20, retaddr);
314         new_eflags = cpu_ldl_kernel_ra(env, tss_base + 0x24, retaddr);
315         for (i = 0; i < 8; i++) {
316             new_regs[i] = cpu_ldl_kernel_ra(env, tss_base + (0x28 + i * 4),
317                                             retaddr);
318         }
319         for (i = 0; i < 6; i++) {
320             new_segs[i] = cpu_lduw_kernel_ra(env, tss_base + (0x48 + i * 4),
321                                              retaddr);
322         }
323         new_ldt = cpu_lduw_kernel_ra(env, tss_base + 0x60, retaddr);
324         new_trap = cpu_ldl_kernel_ra(env, tss_base + 0x64, retaddr);
325     } else {
326         /* 16 bit */
327         new_cr3 = 0;
328         new_eip = cpu_lduw_kernel_ra(env, tss_base + 0x0e, retaddr);
329         new_eflags = cpu_lduw_kernel_ra(env, tss_base + 0x10, retaddr);
330         for (i = 0; i < 8; i++) {
331             new_regs[i] = cpu_lduw_kernel_ra(env, tss_base + (0x12 + i * 2), retaddr);
332         }
333         for (i = 0; i < 4; i++) {
334             new_segs[i] = cpu_lduw_kernel_ra(env, tss_base + (0x22 + i * 2),
335                                              retaddr);
336         }
337         new_ldt = cpu_lduw_kernel_ra(env, tss_base + 0x2a, retaddr);
338         new_segs[R_FS] = 0;
339         new_segs[R_GS] = 0;
340         new_trap = 0;
341     }
342     /* XXX: avoid a compiler warning, see
343      http://support.amd.com/us/Processor_TechDocs/24593.pdf
344      chapters 12.2.5 and 13.2.4 on how to implement TSS Trap bit */
345     (void)new_trap;
346 
347     /* NOTE: we must avoid memory exceptions during the task switch,
348        so we make dummy accesses before */
349     /* XXX: it can still fail in some cases, so a bigger hack is
350        necessary to valid the TLB after having done the accesses */
351 
352     v1 = cpu_ldub_kernel_ra(env, env->tr.base, retaddr);
353     v2 = cpu_ldub_kernel_ra(env, env->tr.base + old_tss_limit_max, retaddr);
354     cpu_stb_kernel_ra(env, env->tr.base, v1, retaddr);
355     cpu_stb_kernel_ra(env, env->tr.base + old_tss_limit_max, v2, retaddr);
356 
357     /* clear busy bit (it is restartable) */
358     if (source == SWITCH_TSS_JMP || source == SWITCH_TSS_IRET) {
359         tss_set_busy(env, env->tr.selector, 0, retaddr);
360     }
361     old_eflags = cpu_compute_eflags(env);
362     if (source == SWITCH_TSS_IRET) {
363         old_eflags &= ~NT_MASK;
364     }
365 
366     /* save the current state in the old TSS */
367     if (old_type & 8) {
368         /* 32 bit */
369         cpu_stl_kernel_ra(env, env->tr.base + 0x20, next_eip, retaddr);
370         cpu_stl_kernel_ra(env, env->tr.base + 0x24, old_eflags, retaddr);
371         cpu_stl_kernel_ra(env, env->tr.base + (0x28 + 0 * 4), env->regs[R_EAX], retaddr);
372         cpu_stl_kernel_ra(env, env->tr.base + (0x28 + 1 * 4), env->regs[R_ECX], retaddr);
373         cpu_stl_kernel_ra(env, env->tr.base + (0x28 + 2 * 4), env->regs[R_EDX], retaddr);
374         cpu_stl_kernel_ra(env, env->tr.base + (0x28 + 3 * 4), env->regs[R_EBX], retaddr);
375         cpu_stl_kernel_ra(env, env->tr.base + (0x28 + 4 * 4), env->regs[R_ESP], retaddr);
376         cpu_stl_kernel_ra(env, env->tr.base + (0x28 + 5 * 4), env->regs[R_EBP], retaddr);
377         cpu_stl_kernel_ra(env, env->tr.base + (0x28 + 6 * 4), env->regs[R_ESI], retaddr);
378         cpu_stl_kernel_ra(env, env->tr.base + (0x28 + 7 * 4), env->regs[R_EDI], retaddr);
379         for (i = 0; i < 6; i++) {
380             cpu_stw_kernel_ra(env, env->tr.base + (0x48 + i * 4),
381                               env->segs[i].selector, retaddr);
382         }
383     } else {
384         /* 16 bit */
385         cpu_stw_kernel_ra(env, env->tr.base + 0x0e, next_eip, retaddr);
386         cpu_stw_kernel_ra(env, env->tr.base + 0x10, old_eflags, retaddr);
387         cpu_stw_kernel_ra(env, env->tr.base + (0x12 + 0 * 2), env->regs[R_EAX], retaddr);
388         cpu_stw_kernel_ra(env, env->tr.base + (0x12 + 1 * 2), env->regs[R_ECX], retaddr);
389         cpu_stw_kernel_ra(env, env->tr.base + (0x12 + 2 * 2), env->regs[R_EDX], retaddr);
390         cpu_stw_kernel_ra(env, env->tr.base + (0x12 + 3 * 2), env->regs[R_EBX], retaddr);
391         cpu_stw_kernel_ra(env, env->tr.base + (0x12 + 4 * 2), env->regs[R_ESP], retaddr);
392         cpu_stw_kernel_ra(env, env->tr.base + (0x12 + 5 * 2), env->regs[R_EBP], retaddr);
393         cpu_stw_kernel_ra(env, env->tr.base + (0x12 + 6 * 2), env->regs[R_ESI], retaddr);
394         cpu_stw_kernel_ra(env, env->tr.base + (0x12 + 7 * 2), env->regs[R_EDI], retaddr);
395         for (i = 0; i < 4; i++) {
396             cpu_stw_kernel_ra(env, env->tr.base + (0x22 + i * 2),
397                               env->segs[i].selector, retaddr);
398         }
399     }
400 
401     /* now if an exception occurs, it will occurs in the next task
402        context */
403 
404     if (source == SWITCH_TSS_CALL) {
405         cpu_stw_kernel_ra(env, tss_base, env->tr.selector, retaddr);
406         new_eflags |= NT_MASK;
407     }
408 
409     /* set busy bit */
410     if (source == SWITCH_TSS_JMP || source == SWITCH_TSS_CALL) {
411         tss_set_busy(env, tss_selector, 1, retaddr);
412     }
413 
414     /* set the new CPU state */
415     /* from this point, any exception which occurs can give problems */
416     env->cr[0] |= CR0_TS_MASK;
417     env->hflags |= HF_TS_MASK;
418     env->tr.selector = tss_selector;
419     env->tr.base = tss_base;
420     env->tr.limit = tss_limit;
421     env->tr.flags = e2 & ~DESC_TSS_BUSY_MASK;
422 
423     if ((type & 8) && (env->cr[0] & CR0_PG_MASK)) {
424         cpu_x86_update_cr3(env, new_cr3);
425     }
426 
427     /* load all registers without an exception, then reload them with
428        possible exception */
429     env->eip = new_eip;
430     eflags_mask = TF_MASK | AC_MASK | ID_MASK |
431         IF_MASK | IOPL_MASK | VM_MASK | RF_MASK | NT_MASK;
432     if (type & 8) {
433         cpu_load_eflags(env, new_eflags, eflags_mask);
434         for (i = 0; i < 8; i++) {
435             env->regs[i] = new_regs[i];
436         }
437     } else {
438         cpu_load_eflags(env, new_eflags, eflags_mask & 0xffff);
439         for (i = 0; i < 8; i++) {
440             env->regs[i] = (env->regs[i] & 0xffff0000) | new_regs[i];
441         }
442     }
443     if (new_eflags & VM_MASK) {
444         for (i = 0; i < 6; i++) {
445             load_seg_vm(env, i, new_segs[i]);
446         }
447     } else {
448         /* first just selectors as the rest may trigger exceptions */
449         for (i = 0; i < 6; i++) {
450             cpu_x86_load_seg_cache(env, i, new_segs[i], 0, 0, 0);
451         }
452     }
453 
454     env->ldt.selector = new_ldt & ~4;
455     env->ldt.base = 0;
456     env->ldt.limit = 0;
457     env->ldt.flags = 0;
458 
459     /* load the LDT */
460     if (new_ldt & 4) {
461         raise_exception_err_ra(env, EXCP0A_TSS, new_ldt & 0xfffc, retaddr);
462     }
463 
464     if ((new_ldt & 0xfffc) != 0) {
465         dt = &env->gdt;
466         index = new_ldt & ~7;
467         if ((index + 7) > dt->limit) {
468             raise_exception_err_ra(env, EXCP0A_TSS, new_ldt & 0xfffc, retaddr);
469         }
470         ptr = dt->base + index;
471         e1 = cpu_ldl_kernel_ra(env, ptr, retaddr);
472         e2 = cpu_ldl_kernel_ra(env, ptr + 4, retaddr);
473         if ((e2 & DESC_S_MASK) || ((e2 >> DESC_TYPE_SHIFT) & 0xf) != 2) {
474             raise_exception_err_ra(env, EXCP0A_TSS, new_ldt & 0xfffc, retaddr);
475         }
476         if (!(e2 & DESC_P_MASK)) {
477             raise_exception_err_ra(env, EXCP0A_TSS, new_ldt & 0xfffc, retaddr);
478         }
479         load_seg_cache_raw_dt(&env->ldt, e1, e2);
480     }
481 
482     /* load the segments */
483     if (!(new_eflags & VM_MASK)) {
484         int cpl = new_segs[R_CS] & 3;
485         tss_load_seg(env, R_CS, new_segs[R_CS], cpl, retaddr);
486         tss_load_seg(env, R_SS, new_segs[R_SS], cpl, retaddr);
487         tss_load_seg(env, R_ES, new_segs[R_ES], cpl, retaddr);
488         tss_load_seg(env, R_DS, new_segs[R_DS], cpl, retaddr);
489         tss_load_seg(env, R_FS, new_segs[R_FS], cpl, retaddr);
490         tss_load_seg(env, R_GS, new_segs[R_GS], cpl, retaddr);
491     }
492 
493     /* check that env->eip is in the CS segment limits */
494     if (new_eip > env->segs[R_CS].limit) {
495         /* XXX: different exception if CALL? */
496         raise_exception_err_ra(env, EXCP0D_GPF, 0, retaddr);
497     }
498 
499 #ifndef CONFIG_USER_ONLY
500     /* reset local breakpoints */
501     if (env->dr[7] & DR7_LOCAL_BP_MASK) {
502         cpu_x86_update_dr7(env, env->dr[7] & ~DR7_LOCAL_BP_MASK);
503     }
504 #endif
505     return type >> 3;
506 }
507 
508 static int switch_tss(CPUX86State *env, int tss_selector,
509                       uint32_t e1, uint32_t e2, int source,
510                       uint32_t next_eip)
511 {
512     return switch_tss_ra(env, tss_selector, e1, e2, source, next_eip, 0);
513 }
514 
515 static inline unsigned int get_sp_mask(unsigned int e2)
516 {
517 #ifdef TARGET_X86_64
518     if (e2 & DESC_L_MASK) {
519         return 0;
520     } else
521 #endif
522     if (e2 & DESC_B_MASK) {
523         return 0xffffffff;
524     } else {
525         return 0xffff;
526     }
527 }
528 
529 static int exception_is_fault(int intno)
530 {
531     switch (intno) {
532         /*
533          * #DB can be both fault- and trap-like, but it never sets RF=1
534          * in the RFLAGS value pushed on the stack.
535          */
536     case EXCP01_DB:
537     case EXCP03_INT3:
538     case EXCP04_INTO:
539     case EXCP08_DBLE:
540     case EXCP12_MCHK:
541         return 0;
542     }
543     /* Everything else including reserved exception is a fault.  */
544     return 1;
545 }
546 
547 int exception_has_error_code(int intno)
548 {
549     switch (intno) {
550     case 8:
551     case 10:
552     case 11:
553     case 12:
554     case 13:
555     case 14:
556     case 17:
557         return 1;
558     }
559     return 0;
560 }
561 
562 #ifdef TARGET_X86_64
563 #define SET_ESP(val, sp_mask)                                   \
564     do {                                                        \
565         if ((sp_mask) == 0xffff) {                              \
566             env->regs[R_ESP] = (env->regs[R_ESP] & ~0xffff) |   \
567                 ((val) & 0xffff);                               \
568         } else if ((sp_mask) == 0xffffffffLL) {                 \
569             env->regs[R_ESP] = (uint32_t)(val);                 \
570         } else {                                                \
571             env->regs[R_ESP] = (val);                           \
572         }                                                       \
573     } while (0)
574 #else
575 #define SET_ESP(val, sp_mask)                                   \
576     do {                                                        \
577         env->regs[R_ESP] = (env->regs[R_ESP] & ~(sp_mask)) |    \
578             ((val) & (sp_mask));                                \
579     } while (0)
580 #endif
581 
582 /* in 64-bit machines, this can overflow. So this segment addition macro
583  * can be used to trim the value to 32-bit whenever needed */
584 #define SEG_ADDL(ssp, sp, sp_mask) ((uint32_t)((ssp) + (sp & (sp_mask))))
585 
586 /* XXX: add a is_user flag to have proper security support */
587 #define PUSHW_RA(ssp, sp, sp_mask, val, ra)                      \
588     {                                                            \
589         sp -= 2;                                                 \
590         cpu_stw_kernel_ra(env, (ssp) + (sp & (sp_mask)), (val), ra); \
591     }
592 
593 #define PUSHL_RA(ssp, sp, sp_mask, val, ra)                             \
594     {                                                                   \
595         sp -= 4;                                                        \
596         cpu_stl_kernel_ra(env, SEG_ADDL(ssp, sp, sp_mask), (uint32_t)(val), ra); \
597     }
598 
599 #define POPW_RA(ssp, sp, sp_mask, val, ra)                       \
600     {                                                            \
601         val = cpu_lduw_kernel_ra(env, (ssp) + (sp & (sp_mask)), ra); \
602         sp += 2;                                                 \
603     }
604 
605 #define POPL_RA(ssp, sp, sp_mask, val, ra)                              \
606     {                                                                   \
607         val = (uint32_t)cpu_ldl_kernel_ra(env, SEG_ADDL(ssp, sp, sp_mask), ra); \
608         sp += 4;                                                        \
609     }
610 
611 #define PUSHW(ssp, sp, sp_mask, val) PUSHW_RA(ssp, sp, sp_mask, val, 0)
612 #define PUSHL(ssp, sp, sp_mask, val) PUSHL_RA(ssp, sp, sp_mask, val, 0)
613 #define POPW(ssp, sp, sp_mask, val) POPW_RA(ssp, sp, sp_mask, val, 0)
614 #define POPL(ssp, sp, sp_mask, val) POPL_RA(ssp, sp, sp_mask, val, 0)
615 
616 /* protected mode interrupt */
617 static void do_interrupt_protected(CPUX86State *env, int intno, int is_int,
618                                    int error_code, unsigned int next_eip,
619                                    int is_hw)
620 {
621     SegmentCache *dt;
622     target_ulong ptr, ssp;
623     int type, dpl, selector, ss_dpl, cpl;
624     int has_error_code, new_stack, shift;
625     uint32_t e1, e2, offset, ss = 0, esp, ss_e1 = 0, ss_e2 = 0;
626     uint32_t old_eip, sp_mask, eflags;
627     int vm86 = env->eflags & VM_MASK;
628     bool set_rf;
629 
630     has_error_code = 0;
631     if (!is_int && !is_hw) {
632         has_error_code = exception_has_error_code(intno);
633     }
634     if (is_int) {
635         old_eip = next_eip;
636         set_rf = false;
637     } else {
638         old_eip = env->eip;
639         set_rf = exception_is_fault(intno);
640     }
641 
642     dt = &env->idt;
643     if (intno * 8 + 7 > dt->limit) {
644         raise_exception_err(env, EXCP0D_GPF, intno * 8 + 2);
645     }
646     ptr = dt->base + intno * 8;
647     e1 = cpu_ldl_kernel(env, ptr);
648     e2 = cpu_ldl_kernel(env, ptr + 4);
649     /* check gate type */
650     type = (e2 >> DESC_TYPE_SHIFT) & 0x1f;
651     switch (type) {
652     case 5: /* task gate */
653     case 6: /* 286 interrupt gate */
654     case 7: /* 286 trap gate */
655     case 14: /* 386 interrupt gate */
656     case 15: /* 386 trap gate */
657         break;
658     default:
659         raise_exception_err(env, EXCP0D_GPF, intno * 8 + 2);
660         break;
661     }
662     dpl = (e2 >> DESC_DPL_SHIFT) & 3;
663     cpl = env->hflags & HF_CPL_MASK;
664     /* check privilege if software int */
665     if (is_int && dpl < cpl) {
666         raise_exception_err(env, EXCP0D_GPF, intno * 8 + 2);
667     }
668 
669     if (type == 5) {
670         /* task gate */
671         /* must do that check here to return the correct error code */
672         if (!(e2 & DESC_P_MASK)) {
673             raise_exception_err(env, EXCP0B_NOSEG, intno * 8 + 2);
674         }
675         shift = switch_tss(env, intno * 8, e1, e2, SWITCH_TSS_CALL, old_eip);
676         if (has_error_code) {
677             uint32_t mask;
678 
679             /* push the error code */
680             if (env->segs[R_SS].flags & DESC_B_MASK) {
681                 mask = 0xffffffff;
682             } else {
683                 mask = 0xffff;
684             }
685             esp = (env->regs[R_ESP] - (2 << shift)) & mask;
686             ssp = env->segs[R_SS].base + esp;
687             if (shift) {
688                 cpu_stl_kernel(env, ssp, error_code);
689             } else {
690                 cpu_stw_kernel(env, ssp, error_code);
691             }
692             SET_ESP(esp, mask);
693         }
694         return;
695     }
696 
697     /* Otherwise, trap or interrupt gate */
698 
699     /* check valid bit */
700     if (!(e2 & DESC_P_MASK)) {
701         raise_exception_err(env, EXCP0B_NOSEG, intno * 8 + 2);
702     }
703     selector = e1 >> 16;
704     offset = (e2 & 0xffff0000) | (e1 & 0x0000ffff);
705     if ((selector & 0xfffc) == 0) {
706         raise_exception_err(env, EXCP0D_GPF, 0);
707     }
708     if (load_segment(env, &e1, &e2, selector) != 0) {
709         raise_exception_err(env, EXCP0D_GPF, selector & 0xfffc);
710     }
711     if (!(e2 & DESC_S_MASK) || !(e2 & (DESC_CS_MASK))) {
712         raise_exception_err(env, EXCP0D_GPF, selector & 0xfffc);
713     }
714     dpl = (e2 >> DESC_DPL_SHIFT) & 3;
715     if (dpl > cpl) {
716         raise_exception_err(env, EXCP0D_GPF, selector & 0xfffc);
717     }
718     if (!(e2 & DESC_P_MASK)) {
719         raise_exception_err(env, EXCP0B_NOSEG, selector & 0xfffc);
720     }
721     if (e2 & DESC_C_MASK) {
722         dpl = cpl;
723     }
724     if (dpl < cpl) {
725         /* to inner privilege */
726         get_ss_esp_from_tss(env, &ss, &esp, dpl, 0);
727         if ((ss & 0xfffc) == 0) {
728             raise_exception_err(env, EXCP0A_TSS, ss & 0xfffc);
729         }
730         if ((ss & 3) != dpl) {
731             raise_exception_err(env, EXCP0A_TSS, ss & 0xfffc);
732         }
733         if (load_segment(env, &ss_e1, &ss_e2, ss) != 0) {
734             raise_exception_err(env, EXCP0A_TSS, ss & 0xfffc);
735         }
736         ss_dpl = (ss_e2 >> DESC_DPL_SHIFT) & 3;
737         if (ss_dpl != dpl) {
738             raise_exception_err(env, EXCP0A_TSS, ss & 0xfffc);
739         }
740         if (!(ss_e2 & DESC_S_MASK) ||
741             (ss_e2 & DESC_CS_MASK) ||
742             !(ss_e2 & DESC_W_MASK)) {
743             raise_exception_err(env, EXCP0A_TSS, ss & 0xfffc);
744         }
745         if (!(ss_e2 & DESC_P_MASK)) {
746             raise_exception_err(env, EXCP0A_TSS, ss & 0xfffc);
747         }
748         new_stack = 1;
749         sp_mask = get_sp_mask(ss_e2);
750         ssp = get_seg_base(ss_e1, ss_e2);
751     } else  {
752         /* to same privilege */
753         if (vm86) {
754             raise_exception_err(env, EXCP0D_GPF, selector & 0xfffc);
755         }
756         new_stack = 0;
757         sp_mask = get_sp_mask(env->segs[R_SS].flags);
758         ssp = env->segs[R_SS].base;
759         esp = env->regs[R_ESP];
760     }
761 
762     shift = type >> 3;
763 
764 #if 0
765     /* XXX: check that enough room is available */
766     push_size = 6 + (new_stack << 2) + (has_error_code << 1);
767     if (vm86) {
768         push_size += 8;
769     }
770     push_size <<= shift;
771 #endif
772     eflags = cpu_compute_eflags(env);
773     /*
774      * AMD states that code breakpoint #DBs clear RF=0, Intel leaves it
775      * as is.  AMD behavior could be implemented in check_hw_breakpoints().
776      */
777     if (set_rf) {
778         eflags |= RF_MASK;
779     }
780 
781     if (shift == 1) {
782         if (new_stack) {
783             if (vm86) {
784                 PUSHL(ssp, esp, sp_mask, env->segs[R_GS].selector);
785                 PUSHL(ssp, esp, sp_mask, env->segs[R_FS].selector);
786                 PUSHL(ssp, esp, sp_mask, env->segs[R_DS].selector);
787                 PUSHL(ssp, esp, sp_mask, env->segs[R_ES].selector);
788             }
789             PUSHL(ssp, esp, sp_mask, env->segs[R_SS].selector);
790             PUSHL(ssp, esp, sp_mask, env->regs[R_ESP]);
791         }
792         PUSHL(ssp, esp, sp_mask, eflags);
793         PUSHL(ssp, esp, sp_mask, env->segs[R_CS].selector);
794         PUSHL(ssp, esp, sp_mask, old_eip);
795         if (has_error_code) {
796             PUSHL(ssp, esp, sp_mask, error_code);
797         }
798     } else {
799         if (new_stack) {
800             if (vm86) {
801                 PUSHW(ssp, esp, sp_mask, env->segs[R_GS].selector);
802                 PUSHW(ssp, esp, sp_mask, env->segs[R_FS].selector);
803                 PUSHW(ssp, esp, sp_mask, env->segs[R_DS].selector);
804                 PUSHW(ssp, esp, sp_mask, env->segs[R_ES].selector);
805             }
806             PUSHW(ssp, esp, sp_mask, env->segs[R_SS].selector);
807             PUSHW(ssp, esp, sp_mask, env->regs[R_ESP]);
808         }
809         PUSHW(ssp, esp, sp_mask, eflags);
810         PUSHW(ssp, esp, sp_mask, env->segs[R_CS].selector);
811         PUSHW(ssp, esp, sp_mask, old_eip);
812         if (has_error_code) {
813             PUSHW(ssp, esp, sp_mask, error_code);
814         }
815     }
816 
817     /* interrupt gate clear IF mask */
818     if ((type & 1) == 0) {
819         env->eflags &= ~IF_MASK;
820     }
821     env->eflags &= ~(TF_MASK | VM_MASK | RF_MASK | NT_MASK);
822 
823     if (new_stack) {
824         if (vm86) {
825             cpu_x86_load_seg_cache(env, R_ES, 0, 0, 0, 0);
826             cpu_x86_load_seg_cache(env, R_DS, 0, 0, 0, 0);
827             cpu_x86_load_seg_cache(env, R_FS, 0, 0, 0, 0);
828             cpu_x86_load_seg_cache(env, R_GS, 0, 0, 0, 0);
829         }
830         ss = (ss & ~3) | dpl;
831         cpu_x86_load_seg_cache(env, R_SS, ss,
832                                ssp, get_seg_limit(ss_e1, ss_e2), ss_e2);
833     }
834     SET_ESP(esp, sp_mask);
835 
836     selector = (selector & ~3) | dpl;
837     cpu_x86_load_seg_cache(env, R_CS, selector,
838                    get_seg_base(e1, e2),
839                    get_seg_limit(e1, e2),
840                    e2);
841     env->eip = offset;
842 }
843 
844 #ifdef TARGET_X86_64
845 
846 #define PUSHQ_RA(sp, val, ra)                   \
847     {                                           \
848         sp -= 8;                                \
849         cpu_stq_kernel_ra(env, sp, (val), ra);  \
850     }
851 
852 #define POPQ_RA(sp, val, ra)                    \
853     {                                           \
854         val = cpu_ldq_kernel_ra(env, sp, ra);   \
855         sp += 8;                                \
856     }
857 
858 #define PUSHQ(sp, val) PUSHQ_RA(sp, val, 0)
859 #define POPQ(sp, val) POPQ_RA(sp, val, 0)
860 
861 static inline target_ulong get_rsp_from_tss(CPUX86State *env, int level)
862 {
863     X86CPU *cpu = env_archcpu(env);
864     int index, pg_mode;
865     target_ulong rsp;
866     int32_t sext;
867 
868 #if 0
869     printf("TR: base=" TARGET_FMT_lx " limit=%x\n",
870            env->tr.base, env->tr.limit);
871 #endif
872 
873     if (!(env->tr.flags & DESC_P_MASK)) {
874         cpu_abort(CPU(cpu), "invalid tss");
875     }
876     index = 8 * level + 4;
877     if ((index + 7) > env->tr.limit) {
878         raise_exception_err(env, EXCP0A_TSS, env->tr.selector & 0xfffc);
879     }
880 
881     rsp = cpu_ldq_kernel(env, env->tr.base + index);
882 
883     /* test virtual address sign extension */
884     pg_mode = get_pg_mode(env);
885     sext = (int64_t)rsp >> (pg_mode & PG_MODE_LA57 ? 56 : 47);
886     if (sext != 0 && sext != -1) {
887         raise_exception_err(env, EXCP0C_STACK, 0);
888     }
889 
890     return rsp;
891 }
892 
893 /* 64 bit interrupt */
894 static void do_interrupt64(CPUX86State *env, int intno, int is_int,
895                            int error_code, target_ulong next_eip, int is_hw)
896 {
897     SegmentCache *dt;
898     target_ulong ptr;
899     int type, dpl, selector, cpl, ist;
900     int has_error_code, new_stack;
901     uint32_t e1, e2, e3, ss, eflags;
902     target_ulong old_eip, esp, offset;
903     bool set_rf;
904 
905     has_error_code = 0;
906     if (!is_int && !is_hw) {
907         has_error_code = exception_has_error_code(intno);
908     }
909     if (is_int) {
910         old_eip = next_eip;
911         set_rf = false;
912     } else {
913         old_eip = env->eip;
914         set_rf = exception_is_fault(intno);
915     }
916 
917     dt = &env->idt;
918     if (intno * 16 + 15 > dt->limit) {
919         raise_exception_err(env, EXCP0D_GPF, intno * 8 + 2);
920     }
921     ptr = dt->base + intno * 16;
922     e1 = cpu_ldl_kernel(env, ptr);
923     e2 = cpu_ldl_kernel(env, ptr + 4);
924     e3 = cpu_ldl_kernel(env, ptr + 8);
925     /* check gate type */
926     type = (e2 >> DESC_TYPE_SHIFT) & 0x1f;
927     switch (type) {
928     case 14: /* 386 interrupt gate */
929     case 15: /* 386 trap gate */
930         break;
931     default:
932         raise_exception_err(env, EXCP0D_GPF, intno * 8 + 2);
933         break;
934     }
935     dpl = (e2 >> DESC_DPL_SHIFT) & 3;
936     cpl = env->hflags & HF_CPL_MASK;
937     /* check privilege if software int */
938     if (is_int && dpl < cpl) {
939         raise_exception_err(env, EXCP0D_GPF, intno * 8 + 2);
940     }
941     /* check valid bit */
942     if (!(e2 & DESC_P_MASK)) {
943         raise_exception_err(env, EXCP0B_NOSEG, intno * 8 + 2);
944     }
945     selector = e1 >> 16;
946     offset = ((target_ulong)e3 << 32) | (e2 & 0xffff0000) | (e1 & 0x0000ffff);
947     ist = e2 & 7;
948     if ((selector & 0xfffc) == 0) {
949         raise_exception_err(env, EXCP0D_GPF, 0);
950     }
951 
952     if (load_segment(env, &e1, &e2, selector) != 0) {
953         raise_exception_err(env, EXCP0D_GPF, selector & 0xfffc);
954     }
955     if (!(e2 & DESC_S_MASK) || !(e2 & (DESC_CS_MASK))) {
956         raise_exception_err(env, EXCP0D_GPF, selector & 0xfffc);
957     }
958     dpl = (e2 >> DESC_DPL_SHIFT) & 3;
959     if (dpl > cpl) {
960         raise_exception_err(env, EXCP0D_GPF, selector & 0xfffc);
961     }
962     if (!(e2 & DESC_P_MASK)) {
963         raise_exception_err(env, EXCP0B_NOSEG, selector & 0xfffc);
964     }
965     if (!(e2 & DESC_L_MASK) || (e2 & DESC_B_MASK)) {
966         raise_exception_err(env, EXCP0D_GPF, selector & 0xfffc);
967     }
968     if (e2 & DESC_C_MASK) {
969         dpl = cpl;
970     }
971     if (dpl < cpl || ist != 0) {
972         /* to inner privilege */
973         new_stack = 1;
974         esp = get_rsp_from_tss(env, ist != 0 ? ist + 3 : dpl);
975         ss = 0;
976     } else {
977         /* to same privilege */
978         if (env->eflags & VM_MASK) {
979             raise_exception_err(env, EXCP0D_GPF, selector & 0xfffc);
980         }
981         new_stack = 0;
982         esp = env->regs[R_ESP];
983     }
984     esp &= ~0xfLL; /* align stack */
985 
986     /* See do_interrupt_protected.  */
987     eflags = cpu_compute_eflags(env);
988     if (set_rf) {
989         eflags |= RF_MASK;
990     }
991 
992     PUSHQ(esp, env->segs[R_SS].selector);
993     PUSHQ(esp, env->regs[R_ESP]);
994     PUSHQ(esp, eflags);
995     PUSHQ(esp, env->segs[R_CS].selector);
996     PUSHQ(esp, old_eip);
997     if (has_error_code) {
998         PUSHQ(esp, error_code);
999     }
1000 
1001     /* interrupt gate clear IF mask */
1002     if ((type & 1) == 0) {
1003         env->eflags &= ~IF_MASK;
1004     }
1005     env->eflags &= ~(TF_MASK | VM_MASK | RF_MASK | NT_MASK);
1006 
1007     if (new_stack) {
1008         ss = 0 | dpl;
1009         cpu_x86_load_seg_cache(env, R_SS, ss, 0, 0, dpl << DESC_DPL_SHIFT);
1010     }
1011     env->regs[R_ESP] = esp;
1012 
1013     selector = (selector & ~3) | dpl;
1014     cpu_x86_load_seg_cache(env, R_CS, selector,
1015                    get_seg_base(e1, e2),
1016                    get_seg_limit(e1, e2),
1017                    e2);
1018     env->eip = offset;
1019 }
1020 #endif /* TARGET_X86_64 */
1021 
1022 void helper_sysret(CPUX86State *env, int dflag)
1023 {
1024     int cpl, selector;
1025 
1026     if (!(env->efer & MSR_EFER_SCE)) {
1027         raise_exception_err_ra(env, EXCP06_ILLOP, 0, GETPC());
1028     }
1029     cpl = env->hflags & HF_CPL_MASK;
1030     if (!(env->cr[0] & CR0_PE_MASK) || cpl != 0) {
1031         raise_exception_err_ra(env, EXCP0D_GPF, 0, GETPC());
1032     }
1033     selector = (env->star >> 48) & 0xffff;
1034 #ifdef TARGET_X86_64
1035     if (env->hflags & HF_LMA_MASK) {
1036         cpu_load_eflags(env, (uint32_t)(env->regs[11]), TF_MASK | AC_MASK
1037                         | ID_MASK | IF_MASK | IOPL_MASK | VM_MASK | RF_MASK |
1038                         NT_MASK);
1039         if (dflag == 2) {
1040             cpu_x86_load_seg_cache(env, R_CS, (selector + 16) | 3,
1041                                    0, 0xffffffff,
1042                                    DESC_G_MASK | DESC_P_MASK |
1043                                    DESC_S_MASK | (3 << DESC_DPL_SHIFT) |
1044                                    DESC_CS_MASK | DESC_R_MASK | DESC_A_MASK |
1045                                    DESC_L_MASK);
1046             env->eip = env->regs[R_ECX];
1047         } else {
1048             cpu_x86_load_seg_cache(env, R_CS, selector | 3,
1049                                    0, 0xffffffff,
1050                                    DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
1051                                    DESC_S_MASK | (3 << DESC_DPL_SHIFT) |
1052                                    DESC_CS_MASK | DESC_R_MASK | DESC_A_MASK);
1053             env->eip = (uint32_t)env->regs[R_ECX];
1054         }
1055         cpu_x86_load_seg_cache(env, R_SS, (selector + 8) | 3,
1056                                0, 0xffffffff,
1057                                DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
1058                                DESC_S_MASK | (3 << DESC_DPL_SHIFT) |
1059                                DESC_W_MASK | DESC_A_MASK);
1060     } else
1061 #endif
1062     {
1063         env->eflags |= IF_MASK;
1064         cpu_x86_load_seg_cache(env, R_CS, selector | 3,
1065                                0, 0xffffffff,
1066                                DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
1067                                DESC_S_MASK | (3 << DESC_DPL_SHIFT) |
1068                                DESC_CS_MASK | DESC_R_MASK | DESC_A_MASK);
1069         env->eip = (uint32_t)env->regs[R_ECX];
1070         cpu_x86_load_seg_cache(env, R_SS, (selector + 8) | 3,
1071                                0, 0xffffffff,
1072                                DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
1073                                DESC_S_MASK | (3 << DESC_DPL_SHIFT) |
1074                                DESC_W_MASK | DESC_A_MASK);
1075     }
1076 }
1077 
1078 /* real mode interrupt */
1079 static void do_interrupt_real(CPUX86State *env, int intno, int is_int,
1080                               int error_code, unsigned int next_eip)
1081 {
1082     SegmentCache *dt;
1083     target_ulong ptr, ssp;
1084     int selector;
1085     uint32_t offset, esp;
1086     uint32_t old_cs, old_eip;
1087 
1088     /* real mode (simpler!) */
1089     dt = &env->idt;
1090     if (intno * 4 + 3 > dt->limit) {
1091         raise_exception_err(env, EXCP0D_GPF, intno * 8 + 2);
1092     }
1093     ptr = dt->base + intno * 4;
1094     offset = cpu_lduw_kernel(env, ptr);
1095     selector = cpu_lduw_kernel(env, ptr + 2);
1096     esp = env->regs[R_ESP];
1097     ssp = env->segs[R_SS].base;
1098     if (is_int) {
1099         old_eip = next_eip;
1100     } else {
1101         old_eip = env->eip;
1102     }
1103     old_cs = env->segs[R_CS].selector;
1104     /* XXX: use SS segment size? */
1105     PUSHW(ssp, esp, 0xffff, cpu_compute_eflags(env));
1106     PUSHW(ssp, esp, 0xffff, old_cs);
1107     PUSHW(ssp, esp, 0xffff, old_eip);
1108 
1109     /* update processor state */
1110     env->regs[R_ESP] = (env->regs[R_ESP] & ~0xffff) | (esp & 0xffff);
1111     env->eip = offset;
1112     env->segs[R_CS].selector = selector;
1113     env->segs[R_CS].base = (selector << 4);
1114     env->eflags &= ~(IF_MASK | TF_MASK | AC_MASK | RF_MASK);
1115 }
1116 
1117 /*
1118  * Begin execution of an interruption. is_int is TRUE if coming from
1119  * the int instruction. next_eip is the env->eip value AFTER the interrupt
1120  * instruction. It is only relevant if is_int is TRUE.
1121  */
1122 void do_interrupt_all(X86CPU *cpu, int intno, int is_int,
1123                       int error_code, target_ulong next_eip, int is_hw)
1124 {
1125     CPUX86State *env = &cpu->env;
1126 
1127     if (qemu_loglevel_mask(CPU_LOG_INT)) {
1128         if ((env->cr[0] & CR0_PE_MASK)) {
1129             static int count;
1130 
1131             qemu_log("%6d: v=%02x e=%04x i=%d cpl=%d IP=%04x:" TARGET_FMT_lx
1132                      " pc=" TARGET_FMT_lx " SP=%04x:" TARGET_FMT_lx,
1133                      count, intno, error_code, is_int,
1134                      env->hflags & HF_CPL_MASK,
1135                      env->segs[R_CS].selector, env->eip,
1136                      (int)env->segs[R_CS].base + env->eip,
1137                      env->segs[R_SS].selector, env->regs[R_ESP]);
1138             if (intno == 0x0e) {
1139                 qemu_log(" CR2=" TARGET_FMT_lx, env->cr[2]);
1140             } else {
1141                 qemu_log(" env->regs[R_EAX]=" TARGET_FMT_lx, env->regs[R_EAX]);
1142             }
1143             qemu_log("\n");
1144             log_cpu_state(CPU(cpu), CPU_DUMP_CCOP);
1145 #if 0
1146             {
1147                 int i;
1148                 target_ulong ptr;
1149 
1150                 qemu_log("       code=");
1151                 ptr = env->segs[R_CS].base + env->eip;
1152                 for (i = 0; i < 16; i++) {
1153                     qemu_log(" %02x", ldub(ptr + i));
1154                 }
1155                 qemu_log("\n");
1156             }
1157 #endif
1158             count++;
1159         }
1160     }
1161     if (env->cr[0] & CR0_PE_MASK) {
1162 #if !defined(CONFIG_USER_ONLY)
1163         if (env->hflags & HF_GUEST_MASK) {
1164             handle_even_inj(env, intno, is_int, error_code, is_hw, 0);
1165         }
1166 #endif
1167 #ifdef TARGET_X86_64
1168         if (env->hflags & HF_LMA_MASK) {
1169             do_interrupt64(env, intno, is_int, error_code, next_eip, is_hw);
1170         } else
1171 #endif
1172         {
1173             do_interrupt_protected(env, intno, is_int, error_code, next_eip,
1174                                    is_hw);
1175         }
1176     } else {
1177 #if !defined(CONFIG_USER_ONLY)
1178         if (env->hflags & HF_GUEST_MASK) {
1179             handle_even_inj(env, intno, is_int, error_code, is_hw, 1);
1180         }
1181 #endif
1182         do_interrupt_real(env, intno, is_int, error_code, next_eip);
1183     }
1184 
1185 #if !defined(CONFIG_USER_ONLY)
1186     if (env->hflags & HF_GUEST_MASK) {
1187         CPUState *cs = CPU(cpu);
1188         uint32_t event_inj = x86_ldl_phys(cs, env->vm_vmcb +
1189                                       offsetof(struct vmcb,
1190                                                control.event_inj));
1191 
1192         x86_stl_phys(cs,
1193                  env->vm_vmcb + offsetof(struct vmcb, control.event_inj),
1194                  event_inj & ~SVM_EVTINJ_VALID);
1195     }
1196 #endif
1197 }
1198 
1199 void do_interrupt_x86_hardirq(CPUX86State *env, int intno, int is_hw)
1200 {
1201     do_interrupt_all(env_archcpu(env), intno, 0, 0, 0, is_hw);
1202 }
1203 
1204 void helper_lldt(CPUX86State *env, int selector)
1205 {
1206     SegmentCache *dt;
1207     uint32_t e1, e2;
1208     int index, entry_limit;
1209     target_ulong ptr;
1210 
1211     selector &= 0xffff;
1212     if ((selector & 0xfffc) == 0) {
1213         /* XXX: NULL selector case: invalid LDT */
1214         env->ldt.base = 0;
1215         env->ldt.limit = 0;
1216     } else {
1217         if (selector & 0x4) {
1218             raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1219         }
1220         dt = &env->gdt;
1221         index = selector & ~7;
1222 #ifdef TARGET_X86_64
1223         if (env->hflags & HF_LMA_MASK) {
1224             entry_limit = 15;
1225         } else
1226 #endif
1227         {
1228             entry_limit = 7;
1229         }
1230         if ((index + entry_limit) > dt->limit) {
1231             raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1232         }
1233         ptr = dt->base + index;
1234         e1 = cpu_ldl_kernel_ra(env, ptr, GETPC());
1235         e2 = cpu_ldl_kernel_ra(env, ptr + 4, GETPC());
1236         if ((e2 & DESC_S_MASK) || ((e2 >> DESC_TYPE_SHIFT) & 0xf) != 2) {
1237             raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1238         }
1239         if (!(e2 & DESC_P_MASK)) {
1240             raise_exception_err_ra(env, EXCP0B_NOSEG, selector & 0xfffc, GETPC());
1241         }
1242 #ifdef TARGET_X86_64
1243         if (env->hflags & HF_LMA_MASK) {
1244             uint32_t e3;
1245 
1246             e3 = cpu_ldl_kernel_ra(env, ptr + 8, GETPC());
1247             load_seg_cache_raw_dt(&env->ldt, e1, e2);
1248             env->ldt.base |= (target_ulong)e3 << 32;
1249         } else
1250 #endif
1251         {
1252             load_seg_cache_raw_dt(&env->ldt, e1, e2);
1253         }
1254     }
1255     env->ldt.selector = selector;
1256 }
1257 
1258 void helper_ltr(CPUX86State *env, int selector)
1259 {
1260     SegmentCache *dt;
1261     uint32_t e1, e2;
1262     int index, type, entry_limit;
1263     target_ulong ptr;
1264 
1265     selector &= 0xffff;
1266     if ((selector & 0xfffc) == 0) {
1267         /* NULL selector case: invalid TR */
1268         env->tr.base = 0;
1269         env->tr.limit = 0;
1270         env->tr.flags = 0;
1271     } else {
1272         if (selector & 0x4) {
1273             raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1274         }
1275         dt = &env->gdt;
1276         index = selector & ~7;
1277 #ifdef TARGET_X86_64
1278         if (env->hflags & HF_LMA_MASK) {
1279             entry_limit = 15;
1280         } else
1281 #endif
1282         {
1283             entry_limit = 7;
1284         }
1285         if ((index + entry_limit) > dt->limit) {
1286             raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1287         }
1288         ptr = dt->base + index;
1289         e1 = cpu_ldl_kernel_ra(env, ptr, GETPC());
1290         e2 = cpu_ldl_kernel_ra(env, ptr + 4, GETPC());
1291         type = (e2 >> DESC_TYPE_SHIFT) & 0xf;
1292         if ((e2 & DESC_S_MASK) ||
1293             (type != 1 && type != 9)) {
1294             raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1295         }
1296         if (!(e2 & DESC_P_MASK)) {
1297             raise_exception_err_ra(env, EXCP0B_NOSEG, selector & 0xfffc, GETPC());
1298         }
1299 #ifdef TARGET_X86_64
1300         if (env->hflags & HF_LMA_MASK) {
1301             uint32_t e3, e4;
1302 
1303             e3 = cpu_ldl_kernel_ra(env, ptr + 8, GETPC());
1304             e4 = cpu_ldl_kernel_ra(env, ptr + 12, GETPC());
1305             if ((e4 >> DESC_TYPE_SHIFT) & 0xf) {
1306                 raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1307             }
1308             load_seg_cache_raw_dt(&env->tr, e1, e2);
1309             env->tr.base |= (target_ulong)e3 << 32;
1310         } else
1311 #endif
1312         {
1313             load_seg_cache_raw_dt(&env->tr, e1, e2);
1314         }
1315         e2 |= DESC_TSS_BUSY_MASK;
1316         cpu_stl_kernel_ra(env, ptr + 4, e2, GETPC());
1317     }
1318     env->tr.selector = selector;
1319 }
1320 
1321 /* only works if protected mode and not VM86. seg_reg must be != R_CS */
1322 void helper_load_seg(CPUX86State *env, int seg_reg, int selector)
1323 {
1324     uint32_t e1, e2;
1325     int cpl, dpl, rpl;
1326     SegmentCache *dt;
1327     int index;
1328     target_ulong ptr;
1329 
1330     selector &= 0xffff;
1331     cpl = env->hflags & HF_CPL_MASK;
1332     if ((selector & 0xfffc) == 0) {
1333         /* null selector case */
1334         if (seg_reg == R_SS
1335 #ifdef TARGET_X86_64
1336             && (!(env->hflags & HF_CS64_MASK) || cpl == 3)
1337 #endif
1338             ) {
1339             raise_exception_err_ra(env, EXCP0D_GPF, 0, GETPC());
1340         }
1341         cpu_x86_load_seg_cache(env, seg_reg, selector, 0, 0, 0);
1342     } else {
1343 
1344         if (selector & 0x4) {
1345             dt = &env->ldt;
1346         } else {
1347             dt = &env->gdt;
1348         }
1349         index = selector & ~7;
1350         if ((index + 7) > dt->limit) {
1351             raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1352         }
1353         ptr = dt->base + index;
1354         e1 = cpu_ldl_kernel_ra(env, ptr, GETPC());
1355         e2 = cpu_ldl_kernel_ra(env, ptr + 4, GETPC());
1356 
1357         if (!(e2 & DESC_S_MASK)) {
1358             raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1359         }
1360         rpl = selector & 3;
1361         dpl = (e2 >> DESC_DPL_SHIFT) & 3;
1362         if (seg_reg == R_SS) {
1363             /* must be writable segment */
1364             if ((e2 & DESC_CS_MASK) || !(e2 & DESC_W_MASK)) {
1365                 raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1366             }
1367             if (rpl != cpl || dpl != cpl) {
1368                 raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1369             }
1370         } else {
1371             /* must be readable segment */
1372             if ((e2 & (DESC_CS_MASK | DESC_R_MASK)) == DESC_CS_MASK) {
1373                 raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1374             }
1375 
1376             if (!(e2 & DESC_CS_MASK) || !(e2 & DESC_C_MASK)) {
1377                 /* if not conforming code, test rights */
1378                 if (dpl < cpl || dpl < rpl) {
1379                     raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1380                 }
1381             }
1382         }
1383 
1384         if (!(e2 & DESC_P_MASK)) {
1385             if (seg_reg == R_SS) {
1386                 raise_exception_err_ra(env, EXCP0C_STACK, selector & 0xfffc, GETPC());
1387             } else {
1388                 raise_exception_err_ra(env, EXCP0B_NOSEG, selector & 0xfffc, GETPC());
1389             }
1390         }
1391 
1392         /* set the access bit if not already set */
1393         if (!(e2 & DESC_A_MASK)) {
1394             e2 |= DESC_A_MASK;
1395             cpu_stl_kernel_ra(env, ptr + 4, e2, GETPC());
1396         }
1397 
1398         cpu_x86_load_seg_cache(env, seg_reg, selector,
1399                        get_seg_base(e1, e2),
1400                        get_seg_limit(e1, e2),
1401                        e2);
1402 #if 0
1403         qemu_log("load_seg: sel=0x%04x base=0x%08lx limit=0x%08lx flags=%08x\n",
1404                 selector, (unsigned long)sc->base, sc->limit, sc->flags);
1405 #endif
1406     }
1407 }
1408 
1409 /* protected mode jump */
1410 void helper_ljmp_protected(CPUX86State *env, int new_cs, target_ulong new_eip,
1411                            target_ulong next_eip)
1412 {
1413     int gate_cs, type;
1414     uint32_t e1, e2, cpl, dpl, rpl, limit;
1415 
1416     if ((new_cs & 0xfffc) == 0) {
1417         raise_exception_err_ra(env, EXCP0D_GPF, 0, GETPC());
1418     }
1419     if (load_segment_ra(env, &e1, &e2, new_cs, GETPC()) != 0) {
1420         raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1421     }
1422     cpl = env->hflags & HF_CPL_MASK;
1423     if (e2 & DESC_S_MASK) {
1424         if (!(e2 & DESC_CS_MASK)) {
1425             raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1426         }
1427         dpl = (e2 >> DESC_DPL_SHIFT) & 3;
1428         if (e2 & DESC_C_MASK) {
1429             /* conforming code segment */
1430             if (dpl > cpl) {
1431                 raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1432             }
1433         } else {
1434             /* non conforming code segment */
1435             rpl = new_cs & 3;
1436             if (rpl > cpl) {
1437                 raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1438             }
1439             if (dpl != cpl) {
1440                 raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1441             }
1442         }
1443         if (!(e2 & DESC_P_MASK)) {
1444             raise_exception_err_ra(env, EXCP0B_NOSEG, new_cs & 0xfffc, GETPC());
1445         }
1446         limit = get_seg_limit(e1, e2);
1447         if (new_eip > limit &&
1448             (!(env->hflags & HF_LMA_MASK) || !(e2 & DESC_L_MASK))) {
1449             raise_exception_err_ra(env, EXCP0D_GPF, 0, GETPC());
1450         }
1451         cpu_x86_load_seg_cache(env, R_CS, (new_cs & 0xfffc) | cpl,
1452                        get_seg_base(e1, e2), limit, e2);
1453         env->eip = new_eip;
1454     } else {
1455         /* jump to call or task gate */
1456         dpl = (e2 >> DESC_DPL_SHIFT) & 3;
1457         rpl = new_cs & 3;
1458         cpl = env->hflags & HF_CPL_MASK;
1459         type = (e2 >> DESC_TYPE_SHIFT) & 0xf;
1460 
1461 #ifdef TARGET_X86_64
1462         if (env->efer & MSR_EFER_LMA) {
1463             if (type != 12) {
1464                 raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1465             }
1466         }
1467 #endif
1468         switch (type) {
1469         case 1: /* 286 TSS */
1470         case 9: /* 386 TSS */
1471         case 5: /* task gate */
1472             if (dpl < cpl || dpl < rpl) {
1473                 raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1474             }
1475             switch_tss_ra(env, new_cs, e1, e2, SWITCH_TSS_JMP, next_eip, GETPC());
1476             break;
1477         case 4: /* 286 call gate */
1478         case 12: /* 386 call gate */
1479             if ((dpl < cpl) || (dpl < rpl)) {
1480                 raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1481             }
1482             if (!(e2 & DESC_P_MASK)) {
1483                 raise_exception_err_ra(env, EXCP0B_NOSEG, new_cs & 0xfffc, GETPC());
1484             }
1485             gate_cs = e1 >> 16;
1486             new_eip = (e1 & 0xffff);
1487             if (type == 12) {
1488                 new_eip |= (e2 & 0xffff0000);
1489             }
1490 
1491 #ifdef TARGET_X86_64
1492             if (env->efer & MSR_EFER_LMA) {
1493                 /* load the upper 8 bytes of the 64-bit call gate */
1494                 if (load_segment_ra(env, &e1, &e2, new_cs + 8, GETPC())) {
1495                     raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc,
1496                                            GETPC());
1497                 }
1498                 type = (e2 >> DESC_TYPE_SHIFT) & 0x1f;
1499                 if (type != 0) {
1500                     raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc,
1501                                            GETPC());
1502                 }
1503                 new_eip |= ((target_ulong)e1) << 32;
1504             }
1505 #endif
1506 
1507             if (load_segment_ra(env, &e1, &e2, gate_cs, GETPC()) != 0) {
1508                 raise_exception_err_ra(env, EXCP0D_GPF, gate_cs & 0xfffc, GETPC());
1509             }
1510             dpl = (e2 >> DESC_DPL_SHIFT) & 3;
1511             /* must be code segment */
1512             if (((e2 & (DESC_S_MASK | DESC_CS_MASK)) !=
1513                  (DESC_S_MASK | DESC_CS_MASK))) {
1514                 raise_exception_err_ra(env, EXCP0D_GPF, gate_cs & 0xfffc, GETPC());
1515             }
1516             if (((e2 & DESC_C_MASK) && (dpl > cpl)) ||
1517                 (!(e2 & DESC_C_MASK) && (dpl != cpl))) {
1518                 raise_exception_err_ra(env, EXCP0D_GPF, gate_cs & 0xfffc, GETPC());
1519             }
1520 #ifdef TARGET_X86_64
1521             if (env->efer & MSR_EFER_LMA) {
1522                 if (!(e2 & DESC_L_MASK)) {
1523                     raise_exception_err_ra(env, EXCP0D_GPF, gate_cs & 0xfffc, GETPC());
1524                 }
1525                 if (e2 & DESC_B_MASK) {
1526                     raise_exception_err_ra(env, EXCP0D_GPF, gate_cs & 0xfffc, GETPC());
1527                 }
1528             }
1529 #endif
1530             if (!(e2 & DESC_P_MASK)) {
1531                 raise_exception_err_ra(env, EXCP0D_GPF, gate_cs & 0xfffc, GETPC());
1532             }
1533             limit = get_seg_limit(e1, e2);
1534             if (new_eip > limit &&
1535                 (!(env->hflags & HF_LMA_MASK) || !(e2 & DESC_L_MASK))) {
1536                 raise_exception_err_ra(env, EXCP0D_GPF, 0, GETPC());
1537             }
1538             cpu_x86_load_seg_cache(env, R_CS, (gate_cs & 0xfffc) | cpl,
1539                                    get_seg_base(e1, e2), limit, e2);
1540             env->eip = new_eip;
1541             break;
1542         default:
1543             raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1544             break;
1545         }
1546     }
1547 }
1548 
1549 /* real mode call */
1550 void helper_lcall_real(CPUX86State *env, uint32_t new_cs, uint32_t new_eip,
1551                        int shift, uint32_t next_eip)
1552 {
1553     uint32_t esp, esp_mask;
1554     target_ulong ssp;
1555 
1556     esp = env->regs[R_ESP];
1557     esp_mask = get_sp_mask(env->segs[R_SS].flags);
1558     ssp = env->segs[R_SS].base;
1559     if (shift) {
1560         PUSHL_RA(ssp, esp, esp_mask, env->segs[R_CS].selector, GETPC());
1561         PUSHL_RA(ssp, esp, esp_mask, next_eip, GETPC());
1562     } else {
1563         PUSHW_RA(ssp, esp, esp_mask, env->segs[R_CS].selector, GETPC());
1564         PUSHW_RA(ssp, esp, esp_mask, next_eip, GETPC());
1565     }
1566 
1567     SET_ESP(esp, esp_mask);
1568     env->eip = new_eip;
1569     env->segs[R_CS].selector = new_cs;
1570     env->segs[R_CS].base = (new_cs << 4);
1571 }
1572 
1573 /* protected mode call */
1574 void helper_lcall_protected(CPUX86State *env, int new_cs, target_ulong new_eip,
1575                             int shift, target_ulong next_eip)
1576 {
1577     int new_stack, i;
1578     uint32_t e1, e2, cpl, dpl, rpl, selector, param_count;
1579     uint32_t ss = 0, ss_e1 = 0, ss_e2 = 0, type, ss_dpl, sp_mask;
1580     uint32_t val, limit, old_sp_mask;
1581     target_ulong ssp, old_ssp, offset, sp;
1582 
1583     LOG_PCALL("lcall %04x:" TARGET_FMT_lx " s=%d\n", new_cs, new_eip, shift);
1584     LOG_PCALL_STATE(env_cpu(env));
1585     if ((new_cs & 0xfffc) == 0) {
1586         raise_exception_err_ra(env, EXCP0D_GPF, 0, GETPC());
1587     }
1588     if (load_segment_ra(env, &e1, &e2, new_cs, GETPC()) != 0) {
1589         raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1590     }
1591     cpl = env->hflags & HF_CPL_MASK;
1592     LOG_PCALL("desc=%08x:%08x\n", e1, e2);
1593     if (e2 & DESC_S_MASK) {
1594         if (!(e2 & DESC_CS_MASK)) {
1595             raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1596         }
1597         dpl = (e2 >> DESC_DPL_SHIFT) & 3;
1598         if (e2 & DESC_C_MASK) {
1599             /* conforming code segment */
1600             if (dpl > cpl) {
1601                 raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1602             }
1603         } else {
1604             /* non conforming code segment */
1605             rpl = new_cs & 3;
1606             if (rpl > cpl) {
1607                 raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1608             }
1609             if (dpl != cpl) {
1610                 raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1611             }
1612         }
1613         if (!(e2 & DESC_P_MASK)) {
1614             raise_exception_err_ra(env, EXCP0B_NOSEG, new_cs & 0xfffc, GETPC());
1615         }
1616 
1617 #ifdef TARGET_X86_64
1618         /* XXX: check 16/32 bit cases in long mode */
1619         if (shift == 2) {
1620             target_ulong rsp;
1621 
1622             /* 64 bit case */
1623             rsp = env->regs[R_ESP];
1624             PUSHQ_RA(rsp, env->segs[R_CS].selector, GETPC());
1625             PUSHQ_RA(rsp, next_eip, GETPC());
1626             /* from this point, not restartable */
1627             env->regs[R_ESP] = rsp;
1628             cpu_x86_load_seg_cache(env, R_CS, (new_cs & 0xfffc) | cpl,
1629                                    get_seg_base(e1, e2),
1630                                    get_seg_limit(e1, e2), e2);
1631             env->eip = new_eip;
1632         } else
1633 #endif
1634         {
1635             sp = env->regs[R_ESP];
1636             sp_mask = get_sp_mask(env->segs[R_SS].flags);
1637             ssp = env->segs[R_SS].base;
1638             if (shift) {
1639                 PUSHL_RA(ssp, sp, sp_mask, env->segs[R_CS].selector, GETPC());
1640                 PUSHL_RA(ssp, sp, sp_mask, next_eip, GETPC());
1641             } else {
1642                 PUSHW_RA(ssp, sp, sp_mask, env->segs[R_CS].selector, GETPC());
1643                 PUSHW_RA(ssp, sp, sp_mask, next_eip, GETPC());
1644             }
1645 
1646             limit = get_seg_limit(e1, e2);
1647             if (new_eip > limit) {
1648                 raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1649             }
1650             /* from this point, not restartable */
1651             SET_ESP(sp, sp_mask);
1652             cpu_x86_load_seg_cache(env, R_CS, (new_cs & 0xfffc) | cpl,
1653                                    get_seg_base(e1, e2), limit, e2);
1654             env->eip = new_eip;
1655         }
1656     } else {
1657         /* check gate type */
1658         type = (e2 >> DESC_TYPE_SHIFT) & 0x1f;
1659         dpl = (e2 >> DESC_DPL_SHIFT) & 3;
1660         rpl = new_cs & 3;
1661 
1662 #ifdef TARGET_X86_64
1663         if (env->efer & MSR_EFER_LMA) {
1664             if (type != 12) {
1665                 raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1666             }
1667         }
1668 #endif
1669 
1670         switch (type) {
1671         case 1: /* available 286 TSS */
1672         case 9: /* available 386 TSS */
1673         case 5: /* task gate */
1674             if (dpl < cpl || dpl < rpl) {
1675                 raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1676             }
1677             switch_tss_ra(env, new_cs, e1, e2, SWITCH_TSS_CALL, next_eip, GETPC());
1678             return;
1679         case 4: /* 286 call gate */
1680         case 12: /* 386 call gate */
1681             break;
1682         default:
1683             raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1684             break;
1685         }
1686         shift = type >> 3;
1687 
1688         if (dpl < cpl || dpl < rpl) {
1689             raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, GETPC());
1690         }
1691         /* check valid bit */
1692         if (!(e2 & DESC_P_MASK)) {
1693             raise_exception_err_ra(env, EXCP0B_NOSEG,  new_cs & 0xfffc, GETPC());
1694         }
1695         selector = e1 >> 16;
1696         param_count = e2 & 0x1f;
1697         offset = (e2 & 0xffff0000) | (e1 & 0x0000ffff);
1698 #ifdef TARGET_X86_64
1699         if (env->efer & MSR_EFER_LMA) {
1700             /* load the upper 8 bytes of the 64-bit call gate */
1701             if (load_segment_ra(env, &e1, &e2, new_cs + 8, GETPC())) {
1702                 raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc,
1703                                        GETPC());
1704             }
1705             type = (e2 >> DESC_TYPE_SHIFT) & 0x1f;
1706             if (type != 0) {
1707                 raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc,
1708                                        GETPC());
1709             }
1710             offset |= ((target_ulong)e1) << 32;
1711         }
1712 #endif
1713         if ((selector & 0xfffc) == 0) {
1714             raise_exception_err_ra(env, EXCP0D_GPF, 0, GETPC());
1715         }
1716 
1717         if (load_segment_ra(env, &e1, &e2, selector, GETPC()) != 0) {
1718             raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1719         }
1720         if (!(e2 & DESC_S_MASK) || !(e2 & (DESC_CS_MASK))) {
1721             raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1722         }
1723         dpl = (e2 >> DESC_DPL_SHIFT) & 3;
1724         if (dpl > cpl) {
1725             raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1726         }
1727 #ifdef TARGET_X86_64
1728         if (env->efer & MSR_EFER_LMA) {
1729             if (!(e2 & DESC_L_MASK)) {
1730                 raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1731             }
1732             if (e2 & DESC_B_MASK) {
1733                 raise_exception_err_ra(env, EXCP0D_GPF, selector & 0xfffc, GETPC());
1734             }
1735             shift++;
1736         }
1737 #endif
1738         if (!(e2 & DESC_P_MASK)) {
1739             raise_exception_err_ra(env, EXCP0B_NOSEG, selector & 0xfffc, GETPC());
1740         }
1741 
1742         if (!(e2 & DESC_C_MASK) && dpl < cpl) {
1743             /* to inner privilege */
1744 #ifdef TARGET_X86_64
1745             if (shift == 2) {
1746                 sp = get_rsp_from_tss(env, dpl);
1747                 ss = dpl;  /* SS = NULL selector with RPL = new CPL */
1748                 new_stack = 1;
1749                 sp_mask = 0;
1750                 ssp = 0;  /* SS base is always zero in IA-32e mode */
1751                 LOG_PCALL("new ss:rsp=%04x:%016llx env->regs[R_ESP]="
1752                           TARGET_FMT_lx "\n", ss, sp, env->regs[R_ESP]);
1753             } else
1754 #endif
1755             {
1756                 uint32_t sp32;
1757                 get_ss_esp_from_tss(env, &ss, &sp32, dpl, GETPC());
1758                 LOG_PCALL("new ss:esp=%04x:%08x param_count=%d env->regs[R_ESP]="
1759                           TARGET_FMT_lx "\n", ss, sp32, param_count,
1760                           env->regs[R_ESP]);
1761                 sp = sp32;
1762                 if ((ss & 0xfffc) == 0) {
1763                     raise_exception_err_ra(env, EXCP0A_TSS, ss & 0xfffc, GETPC());
1764                 }
1765                 if ((ss & 3) != dpl) {
1766                     raise_exception_err_ra(env, EXCP0A_TSS, ss & 0xfffc, GETPC());
1767                 }
1768                 if (load_segment_ra(env, &ss_e1, &ss_e2, ss, GETPC()) != 0) {
1769                     raise_exception_err_ra(env, EXCP0A_TSS, ss & 0xfffc, GETPC());
1770                 }
1771                 ss_dpl = (ss_e2 >> DESC_DPL_SHIFT) & 3;
1772                 if (ss_dpl != dpl) {
1773                     raise_exception_err_ra(env, EXCP0A_TSS, ss & 0xfffc, GETPC());
1774                 }
1775                 if (!(ss_e2 & DESC_S_MASK) ||
1776                     (ss_e2 & DESC_CS_MASK) ||
1777                     !(ss_e2 & DESC_W_MASK)) {
1778                     raise_exception_err_ra(env, EXCP0A_TSS, ss & 0xfffc, GETPC());
1779                 }
1780                 if (!(ss_e2 & DESC_P_MASK)) {
1781                     raise_exception_err_ra(env, EXCP0A_TSS, ss & 0xfffc, GETPC());
1782                 }
1783 
1784                 sp_mask = get_sp_mask(ss_e2);
1785                 ssp = get_seg_base(ss_e1, ss_e2);
1786             }
1787 
1788             /* push_size = ((param_count * 2) + 8) << shift; */
1789 
1790             old_sp_mask = get_sp_mask(env->segs[R_SS].flags);
1791             old_ssp = env->segs[R_SS].base;
1792 #ifdef TARGET_X86_64
1793             if (shift == 2) {
1794                 /* XXX: verify if new stack address is canonical */
1795                 PUSHQ_RA(sp, env->segs[R_SS].selector, GETPC());
1796                 PUSHQ_RA(sp, env->regs[R_ESP], GETPC());
1797                 /* parameters aren't supported for 64-bit call gates */
1798             } else
1799 #endif
1800             if (shift == 1) {
1801                 PUSHL_RA(ssp, sp, sp_mask, env->segs[R_SS].selector, GETPC());
1802                 PUSHL_RA(ssp, sp, sp_mask, env->regs[R_ESP], GETPC());
1803                 for (i = param_count - 1; i >= 0; i--) {
1804                     val = cpu_ldl_kernel_ra(env, old_ssp +
1805                                             ((env->regs[R_ESP] + i * 4) &
1806                                              old_sp_mask), GETPC());
1807                     PUSHL_RA(ssp, sp, sp_mask, val, GETPC());
1808                 }
1809             } else {
1810                 PUSHW_RA(ssp, sp, sp_mask, env->segs[R_SS].selector, GETPC());
1811                 PUSHW_RA(ssp, sp, sp_mask, env->regs[R_ESP], GETPC());
1812                 for (i = param_count - 1; i >= 0; i--) {
1813                     val = cpu_lduw_kernel_ra(env, old_ssp +
1814                                              ((env->regs[R_ESP] + i * 2) &
1815                                               old_sp_mask), GETPC());
1816                     PUSHW_RA(ssp, sp, sp_mask, val, GETPC());
1817                 }
1818             }
1819             new_stack = 1;
1820         } else {
1821             /* to same privilege */
1822             sp = env->regs[R_ESP];
1823             sp_mask = get_sp_mask(env->segs[R_SS].flags);
1824             ssp = env->segs[R_SS].base;
1825             /* push_size = (4 << shift); */
1826             new_stack = 0;
1827         }
1828 
1829 #ifdef TARGET_X86_64
1830         if (shift == 2) {
1831             PUSHQ_RA(sp, env->segs[R_CS].selector, GETPC());
1832             PUSHQ_RA(sp, next_eip, GETPC());
1833         } else
1834 #endif
1835         if (shift == 1) {
1836             PUSHL_RA(ssp, sp, sp_mask, env->segs[R_CS].selector, GETPC());
1837             PUSHL_RA(ssp, sp, sp_mask, next_eip, GETPC());
1838         } else {
1839             PUSHW_RA(ssp, sp, sp_mask, env->segs[R_CS].selector, GETPC());
1840             PUSHW_RA(ssp, sp, sp_mask, next_eip, GETPC());
1841         }
1842 
1843         /* from this point, not restartable */
1844 
1845         if (new_stack) {
1846 #ifdef TARGET_X86_64
1847             if (shift == 2) {
1848                 cpu_x86_load_seg_cache(env, R_SS, ss, 0, 0, 0);
1849             } else
1850 #endif
1851             {
1852                 ss = (ss & ~3) | dpl;
1853                 cpu_x86_load_seg_cache(env, R_SS, ss,
1854                                        ssp,
1855                                        get_seg_limit(ss_e1, ss_e2),
1856                                        ss_e2);
1857             }
1858         }
1859 
1860         selector = (selector & ~3) | dpl;
1861         cpu_x86_load_seg_cache(env, R_CS, selector,
1862                        get_seg_base(e1, e2),
1863                        get_seg_limit(e1, e2),
1864                        e2);
1865         SET_ESP(sp, sp_mask);
1866         env->eip = offset;
1867     }
1868 }
1869 
1870 /* real and vm86 mode iret */
1871 void helper_iret_real(CPUX86State *env, int shift)
1872 {
1873     uint32_t sp, new_cs, new_eip, new_eflags, sp_mask;
1874     target_ulong ssp;
1875     int eflags_mask;
1876 
1877     sp_mask = 0xffff; /* XXXX: use SS segment size? */
1878     sp = env->regs[R_ESP];
1879     ssp = env->segs[R_SS].base;
1880     if (shift == 1) {
1881         /* 32 bits */
1882         POPL_RA(ssp, sp, sp_mask, new_eip, GETPC());
1883         POPL_RA(ssp, sp, sp_mask, new_cs, GETPC());
1884         new_cs &= 0xffff;
1885         POPL_RA(ssp, sp, sp_mask, new_eflags, GETPC());
1886     } else {
1887         /* 16 bits */
1888         POPW_RA(ssp, sp, sp_mask, new_eip, GETPC());
1889         POPW_RA(ssp, sp, sp_mask, new_cs, GETPC());
1890         POPW_RA(ssp, sp, sp_mask, new_eflags, GETPC());
1891     }
1892     env->regs[R_ESP] = (env->regs[R_ESP] & ~sp_mask) | (sp & sp_mask);
1893     env->segs[R_CS].selector = new_cs;
1894     env->segs[R_CS].base = (new_cs << 4);
1895     env->eip = new_eip;
1896     if (env->eflags & VM_MASK) {
1897         eflags_mask = TF_MASK | AC_MASK | ID_MASK | IF_MASK | RF_MASK |
1898             NT_MASK;
1899     } else {
1900         eflags_mask = TF_MASK | AC_MASK | ID_MASK | IF_MASK | IOPL_MASK |
1901             RF_MASK | NT_MASK;
1902     }
1903     if (shift == 0) {
1904         eflags_mask &= 0xffff;
1905     }
1906     cpu_load_eflags(env, new_eflags, eflags_mask);
1907     env->hflags2 &= ~HF2_NMI_MASK;
1908 }
1909 
1910 static inline void validate_seg(CPUX86State *env, X86Seg seg_reg, int cpl)
1911 {
1912     int dpl;
1913     uint32_t e2;
1914 
1915     /* XXX: on x86_64, we do not want to nullify FS and GS because
1916        they may still contain a valid base. I would be interested to
1917        know how a real x86_64 CPU behaves */
1918     if ((seg_reg == R_FS || seg_reg == R_GS) &&
1919         (env->segs[seg_reg].selector & 0xfffc) == 0) {
1920         return;
1921     }
1922 
1923     e2 = env->segs[seg_reg].flags;
1924     dpl = (e2 >> DESC_DPL_SHIFT) & 3;
1925     if (!(e2 & DESC_CS_MASK) || !(e2 & DESC_C_MASK)) {
1926         /* data or non conforming code segment */
1927         if (dpl < cpl) {
1928             cpu_x86_load_seg_cache(env, seg_reg, 0,
1929                                    env->segs[seg_reg].base,
1930                                    env->segs[seg_reg].limit,
1931                                    env->segs[seg_reg].flags & ~DESC_P_MASK);
1932         }
1933     }
1934 }
1935 
1936 /* protected mode iret */
1937 static inline void helper_ret_protected(CPUX86State *env, int shift,
1938                                         int is_iret, int addend,
1939                                         uintptr_t retaddr)
1940 {
1941     uint32_t new_cs, new_eflags, new_ss;
1942     uint32_t new_es, new_ds, new_fs, new_gs;
1943     uint32_t e1, e2, ss_e1, ss_e2;
1944     int cpl, dpl, rpl, eflags_mask, iopl;
1945     target_ulong ssp, sp, new_eip, new_esp, sp_mask;
1946 
1947 #ifdef TARGET_X86_64
1948     if (shift == 2) {
1949         sp_mask = -1;
1950     } else
1951 #endif
1952     {
1953         sp_mask = get_sp_mask(env->segs[R_SS].flags);
1954     }
1955     sp = env->regs[R_ESP];
1956     ssp = env->segs[R_SS].base;
1957     new_eflags = 0; /* avoid warning */
1958 #ifdef TARGET_X86_64
1959     if (shift == 2) {
1960         POPQ_RA(sp, new_eip, retaddr);
1961         POPQ_RA(sp, new_cs, retaddr);
1962         new_cs &= 0xffff;
1963         if (is_iret) {
1964             POPQ_RA(sp, new_eflags, retaddr);
1965         }
1966     } else
1967 #endif
1968     {
1969         if (shift == 1) {
1970             /* 32 bits */
1971             POPL_RA(ssp, sp, sp_mask, new_eip, retaddr);
1972             POPL_RA(ssp, sp, sp_mask, new_cs, retaddr);
1973             new_cs &= 0xffff;
1974             if (is_iret) {
1975                 POPL_RA(ssp, sp, sp_mask, new_eflags, retaddr);
1976                 if (new_eflags & VM_MASK) {
1977                     goto return_to_vm86;
1978                 }
1979             }
1980         } else {
1981             /* 16 bits */
1982             POPW_RA(ssp, sp, sp_mask, new_eip, retaddr);
1983             POPW_RA(ssp, sp, sp_mask, new_cs, retaddr);
1984             if (is_iret) {
1985                 POPW_RA(ssp, sp, sp_mask, new_eflags, retaddr);
1986             }
1987         }
1988     }
1989     LOG_PCALL("lret new %04x:" TARGET_FMT_lx " s=%d addend=0x%x\n",
1990               new_cs, new_eip, shift, addend);
1991     LOG_PCALL_STATE(env_cpu(env));
1992     if ((new_cs & 0xfffc) == 0) {
1993         raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, retaddr);
1994     }
1995     if (load_segment_ra(env, &e1, &e2, new_cs, retaddr) != 0) {
1996         raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, retaddr);
1997     }
1998     if (!(e2 & DESC_S_MASK) ||
1999         !(e2 & DESC_CS_MASK)) {
2000         raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, retaddr);
2001     }
2002     cpl = env->hflags & HF_CPL_MASK;
2003     rpl = new_cs & 3;
2004     if (rpl < cpl) {
2005         raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, retaddr);
2006     }
2007     dpl = (e2 >> DESC_DPL_SHIFT) & 3;
2008     if (e2 & DESC_C_MASK) {
2009         if (dpl > rpl) {
2010             raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, retaddr);
2011         }
2012     } else {
2013         if (dpl != rpl) {
2014             raise_exception_err_ra(env, EXCP0D_GPF, new_cs & 0xfffc, retaddr);
2015         }
2016     }
2017     if (!(e2 & DESC_P_MASK)) {
2018         raise_exception_err_ra(env, EXCP0B_NOSEG, new_cs & 0xfffc, retaddr);
2019     }
2020 
2021     sp += addend;
2022     if (rpl == cpl && (!(env->hflags & HF_CS64_MASK) ||
2023                        ((env->hflags & HF_CS64_MASK) && !is_iret))) {
2024         /* return to same privilege level */
2025         cpu_x86_load_seg_cache(env, R_CS, new_cs,
2026                        get_seg_base(e1, e2),
2027                        get_seg_limit(e1, e2),
2028                        e2);
2029     } else {
2030         /* return to different privilege level */
2031 #ifdef TARGET_X86_64
2032         if (shift == 2) {
2033             POPQ_RA(sp, new_esp, retaddr);
2034             POPQ_RA(sp, new_ss, retaddr);
2035             new_ss &= 0xffff;
2036         } else
2037 #endif
2038         {
2039             if (shift == 1) {
2040                 /* 32 bits */
2041                 POPL_RA(ssp, sp, sp_mask, new_esp, retaddr);
2042                 POPL_RA(ssp, sp, sp_mask, new_ss, retaddr);
2043                 new_ss &= 0xffff;
2044             } else {
2045                 /* 16 bits */
2046                 POPW_RA(ssp, sp, sp_mask, new_esp, retaddr);
2047                 POPW_RA(ssp, sp, sp_mask, new_ss, retaddr);
2048             }
2049         }
2050         LOG_PCALL("new ss:esp=%04x:" TARGET_FMT_lx "\n",
2051                   new_ss, new_esp);
2052         if ((new_ss & 0xfffc) == 0) {
2053 #ifdef TARGET_X86_64
2054             /* NULL ss is allowed in long mode if cpl != 3 */
2055             /* XXX: test CS64? */
2056             if ((env->hflags & HF_LMA_MASK) && rpl != 3) {
2057                 cpu_x86_load_seg_cache(env, R_SS, new_ss,
2058                                        0, 0xffffffff,
2059                                        DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
2060                                        DESC_S_MASK | (rpl << DESC_DPL_SHIFT) |
2061                                        DESC_W_MASK | DESC_A_MASK);
2062                 ss_e2 = DESC_B_MASK; /* XXX: should not be needed? */
2063             } else
2064 #endif
2065             {
2066                 raise_exception_err_ra(env, EXCP0D_GPF, 0, retaddr);
2067             }
2068         } else {
2069             if ((new_ss & 3) != rpl) {
2070                 raise_exception_err_ra(env, EXCP0D_GPF, new_ss & 0xfffc, retaddr);
2071             }
2072             if (load_segment_ra(env, &ss_e1, &ss_e2, new_ss, retaddr) != 0) {
2073                 raise_exception_err_ra(env, EXCP0D_GPF, new_ss & 0xfffc, retaddr);
2074             }
2075             if (!(ss_e2 & DESC_S_MASK) ||
2076                 (ss_e2 & DESC_CS_MASK) ||
2077                 !(ss_e2 & DESC_W_MASK)) {
2078                 raise_exception_err_ra(env, EXCP0D_GPF, new_ss & 0xfffc, retaddr);
2079             }
2080             dpl = (ss_e2 >> DESC_DPL_SHIFT) & 3;
2081             if (dpl != rpl) {
2082                 raise_exception_err_ra(env, EXCP0D_GPF, new_ss & 0xfffc, retaddr);
2083             }
2084             if (!(ss_e2 & DESC_P_MASK)) {
2085                 raise_exception_err_ra(env, EXCP0B_NOSEG, new_ss & 0xfffc, retaddr);
2086             }
2087             cpu_x86_load_seg_cache(env, R_SS, new_ss,
2088                                    get_seg_base(ss_e1, ss_e2),
2089                                    get_seg_limit(ss_e1, ss_e2),
2090                                    ss_e2);
2091         }
2092 
2093         cpu_x86_load_seg_cache(env, R_CS, new_cs,
2094                        get_seg_base(e1, e2),
2095                        get_seg_limit(e1, e2),
2096                        e2);
2097         sp = new_esp;
2098 #ifdef TARGET_X86_64
2099         if (env->hflags & HF_CS64_MASK) {
2100             sp_mask = -1;
2101         } else
2102 #endif
2103         {
2104             sp_mask = get_sp_mask(ss_e2);
2105         }
2106 
2107         /* validate data segments */
2108         validate_seg(env, R_ES, rpl);
2109         validate_seg(env, R_DS, rpl);
2110         validate_seg(env, R_FS, rpl);
2111         validate_seg(env, R_GS, rpl);
2112 
2113         sp += addend;
2114     }
2115     SET_ESP(sp, sp_mask);
2116     env->eip = new_eip;
2117     if (is_iret) {
2118         /* NOTE: 'cpl' is the _old_ CPL */
2119         eflags_mask = TF_MASK | AC_MASK | ID_MASK | RF_MASK | NT_MASK;
2120         if (cpl == 0) {
2121             eflags_mask |= IOPL_MASK;
2122         }
2123         iopl = (env->eflags >> IOPL_SHIFT) & 3;
2124         if (cpl <= iopl) {
2125             eflags_mask |= IF_MASK;
2126         }
2127         if (shift == 0) {
2128             eflags_mask &= 0xffff;
2129         }
2130         cpu_load_eflags(env, new_eflags, eflags_mask);
2131     }
2132     return;
2133 
2134  return_to_vm86:
2135     POPL_RA(ssp, sp, sp_mask, new_esp, retaddr);
2136     POPL_RA(ssp, sp, sp_mask, new_ss, retaddr);
2137     POPL_RA(ssp, sp, sp_mask, new_es, retaddr);
2138     POPL_RA(ssp, sp, sp_mask, new_ds, retaddr);
2139     POPL_RA(ssp, sp, sp_mask, new_fs, retaddr);
2140     POPL_RA(ssp, sp, sp_mask, new_gs, retaddr);
2141 
2142     /* modify processor state */
2143     cpu_load_eflags(env, new_eflags, TF_MASK | AC_MASK | ID_MASK |
2144                     IF_MASK | IOPL_MASK | VM_MASK | NT_MASK | VIF_MASK |
2145                     VIP_MASK);
2146     load_seg_vm(env, R_CS, new_cs & 0xffff);
2147     load_seg_vm(env, R_SS, new_ss & 0xffff);
2148     load_seg_vm(env, R_ES, new_es & 0xffff);
2149     load_seg_vm(env, R_DS, new_ds & 0xffff);
2150     load_seg_vm(env, R_FS, new_fs & 0xffff);
2151     load_seg_vm(env, R_GS, new_gs & 0xffff);
2152 
2153     env->eip = new_eip & 0xffff;
2154     env->regs[R_ESP] = new_esp;
2155 }
2156 
2157 void helper_iret_protected(CPUX86State *env, int shift, int next_eip)
2158 {
2159     int tss_selector, type;
2160     uint32_t e1, e2;
2161 
2162     /* specific case for TSS */
2163     if (env->eflags & NT_MASK) {
2164 #ifdef TARGET_X86_64
2165         if (env->hflags & HF_LMA_MASK) {
2166             raise_exception_err_ra(env, EXCP0D_GPF, 0, GETPC());
2167         }
2168 #endif
2169         tss_selector = cpu_lduw_kernel_ra(env, env->tr.base + 0, GETPC());
2170         if (tss_selector & 4) {
2171             raise_exception_err_ra(env, EXCP0A_TSS, tss_selector & 0xfffc, GETPC());
2172         }
2173         if (load_segment_ra(env, &e1, &e2, tss_selector, GETPC()) != 0) {
2174             raise_exception_err_ra(env, EXCP0A_TSS, tss_selector & 0xfffc, GETPC());
2175         }
2176         type = (e2 >> DESC_TYPE_SHIFT) & 0x17;
2177         /* NOTE: we check both segment and busy TSS */
2178         if (type != 3) {
2179             raise_exception_err_ra(env, EXCP0A_TSS, tss_selector & 0xfffc, GETPC());
2180         }
2181         switch_tss_ra(env, tss_selector, e1, e2, SWITCH_TSS_IRET, next_eip, GETPC());
2182     } else {
2183         helper_ret_protected(env, shift, 1, 0, GETPC());
2184     }
2185     env->hflags2 &= ~HF2_NMI_MASK;
2186 }
2187 
2188 void helper_lret_protected(CPUX86State *env, int shift, int addend)
2189 {
2190     helper_ret_protected(env, shift, 0, addend, GETPC());
2191 }
2192 
2193 void helper_sysenter(CPUX86State *env)
2194 {
2195     if (env->sysenter_cs == 0) {
2196         raise_exception_err_ra(env, EXCP0D_GPF, 0, GETPC());
2197     }
2198     env->eflags &= ~(VM_MASK | IF_MASK | RF_MASK);
2199 
2200 #ifdef TARGET_X86_64
2201     if (env->hflags & HF_LMA_MASK) {
2202         cpu_x86_load_seg_cache(env, R_CS, env->sysenter_cs & 0xfffc,
2203                                0, 0xffffffff,
2204                                DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
2205                                DESC_S_MASK |
2206                                DESC_CS_MASK | DESC_R_MASK | DESC_A_MASK |
2207                                DESC_L_MASK);
2208     } else
2209 #endif
2210     {
2211         cpu_x86_load_seg_cache(env, R_CS, env->sysenter_cs & 0xfffc,
2212                                0, 0xffffffff,
2213                                DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
2214                                DESC_S_MASK |
2215                                DESC_CS_MASK | DESC_R_MASK | DESC_A_MASK);
2216     }
2217     cpu_x86_load_seg_cache(env, R_SS, (env->sysenter_cs + 8) & 0xfffc,
2218                            0, 0xffffffff,
2219                            DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
2220                            DESC_S_MASK |
2221                            DESC_W_MASK | DESC_A_MASK);
2222     env->regs[R_ESP] = env->sysenter_esp;
2223     env->eip = env->sysenter_eip;
2224 }
2225 
2226 void helper_sysexit(CPUX86State *env, int dflag)
2227 {
2228     int cpl;
2229 
2230     cpl = env->hflags & HF_CPL_MASK;
2231     if (env->sysenter_cs == 0 || cpl != 0) {
2232         raise_exception_err_ra(env, EXCP0D_GPF, 0, GETPC());
2233     }
2234 #ifdef TARGET_X86_64
2235     if (dflag == 2) {
2236         cpu_x86_load_seg_cache(env, R_CS, ((env->sysenter_cs + 32) & 0xfffc) |
2237                                3, 0, 0xffffffff,
2238                                DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
2239                                DESC_S_MASK | (3 << DESC_DPL_SHIFT) |
2240                                DESC_CS_MASK | DESC_R_MASK | DESC_A_MASK |
2241                                DESC_L_MASK);
2242         cpu_x86_load_seg_cache(env, R_SS, ((env->sysenter_cs + 40) & 0xfffc) |
2243                                3, 0, 0xffffffff,
2244                                DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
2245                                DESC_S_MASK | (3 << DESC_DPL_SHIFT) |
2246                                DESC_W_MASK | DESC_A_MASK);
2247     } else
2248 #endif
2249     {
2250         cpu_x86_load_seg_cache(env, R_CS, ((env->sysenter_cs + 16) & 0xfffc) |
2251                                3, 0, 0xffffffff,
2252                                DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
2253                                DESC_S_MASK | (3 << DESC_DPL_SHIFT) |
2254                                DESC_CS_MASK | DESC_R_MASK | DESC_A_MASK);
2255         cpu_x86_load_seg_cache(env, R_SS, ((env->sysenter_cs + 24) & 0xfffc) |
2256                                3, 0, 0xffffffff,
2257                                DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
2258                                DESC_S_MASK | (3 << DESC_DPL_SHIFT) |
2259                                DESC_W_MASK | DESC_A_MASK);
2260     }
2261     env->regs[R_ESP] = env->regs[R_ECX];
2262     env->eip = env->regs[R_EDX];
2263 }
2264 
2265 target_ulong helper_lsl(CPUX86State *env, target_ulong selector1)
2266 {
2267     unsigned int limit;
2268     uint32_t e1, e2, selector;
2269     int rpl, dpl, cpl, type;
2270 
2271     selector = selector1 & 0xffff;
2272     assert(CC_OP == CC_OP_EFLAGS);
2273     if ((selector & 0xfffc) == 0) {
2274         goto fail;
2275     }
2276     if (load_segment_ra(env, &e1, &e2, selector, GETPC()) != 0) {
2277         goto fail;
2278     }
2279     rpl = selector & 3;
2280     dpl = (e2 >> DESC_DPL_SHIFT) & 3;
2281     cpl = env->hflags & HF_CPL_MASK;
2282     if (e2 & DESC_S_MASK) {
2283         if ((e2 & DESC_CS_MASK) && (e2 & DESC_C_MASK)) {
2284             /* conforming */
2285         } else {
2286             if (dpl < cpl || dpl < rpl) {
2287                 goto fail;
2288             }
2289         }
2290     } else {
2291         type = (e2 >> DESC_TYPE_SHIFT) & 0xf;
2292         switch (type) {
2293         case 1:
2294         case 2:
2295         case 3:
2296         case 9:
2297         case 11:
2298             break;
2299         default:
2300             goto fail;
2301         }
2302         if (dpl < cpl || dpl < rpl) {
2303         fail:
2304             CC_SRC &= ~CC_Z;
2305             return 0;
2306         }
2307     }
2308     limit = get_seg_limit(e1, e2);
2309     CC_SRC |= CC_Z;
2310     return limit;
2311 }
2312 
2313 target_ulong helper_lar(CPUX86State *env, target_ulong selector1)
2314 {
2315     uint32_t e1, e2, selector;
2316     int rpl, dpl, cpl, type;
2317 
2318     selector = selector1 & 0xffff;
2319     assert(CC_OP == CC_OP_EFLAGS);
2320     if ((selector & 0xfffc) == 0) {
2321         goto fail;
2322     }
2323     if (load_segment_ra(env, &e1, &e2, selector, GETPC()) != 0) {
2324         goto fail;
2325     }
2326     rpl = selector & 3;
2327     dpl = (e2 >> DESC_DPL_SHIFT) & 3;
2328     cpl = env->hflags & HF_CPL_MASK;
2329     if (e2 & DESC_S_MASK) {
2330         if ((e2 & DESC_CS_MASK) && (e2 & DESC_C_MASK)) {
2331             /* conforming */
2332         } else {
2333             if (dpl < cpl || dpl < rpl) {
2334                 goto fail;
2335             }
2336         }
2337     } else {
2338         type = (e2 >> DESC_TYPE_SHIFT) & 0xf;
2339         switch (type) {
2340         case 1:
2341         case 2:
2342         case 3:
2343         case 4:
2344         case 5:
2345         case 9:
2346         case 11:
2347         case 12:
2348             break;
2349         default:
2350             goto fail;
2351         }
2352         if (dpl < cpl || dpl < rpl) {
2353         fail:
2354             CC_SRC &= ~CC_Z;
2355             return 0;
2356         }
2357     }
2358     CC_SRC |= CC_Z;
2359     return e2 & 0x00f0ff00;
2360 }
2361 
2362 void helper_verr(CPUX86State *env, target_ulong selector1)
2363 {
2364     uint32_t e1, e2, eflags, selector;
2365     int rpl, dpl, cpl;
2366 
2367     selector = selector1 & 0xffff;
2368     eflags = cpu_cc_compute_all(env) | CC_Z;
2369     if ((selector & 0xfffc) == 0) {
2370         goto fail;
2371     }
2372     if (load_segment_ra(env, &e1, &e2, selector, GETPC()) != 0) {
2373         goto fail;
2374     }
2375     if (!(e2 & DESC_S_MASK)) {
2376         goto fail;
2377     }
2378     rpl = selector & 3;
2379     dpl = (e2 >> DESC_DPL_SHIFT) & 3;
2380     cpl = env->hflags & HF_CPL_MASK;
2381     if (e2 & DESC_CS_MASK) {
2382         if (!(e2 & DESC_R_MASK)) {
2383             goto fail;
2384         }
2385         if (!(e2 & DESC_C_MASK)) {
2386             if (dpl < cpl || dpl < rpl) {
2387                 goto fail;
2388             }
2389         }
2390     } else {
2391         if (dpl < cpl || dpl < rpl) {
2392         fail:
2393             eflags &= ~CC_Z;
2394         }
2395     }
2396     CC_SRC = eflags;
2397     CC_OP = CC_OP_EFLAGS;
2398 }
2399 
2400 void helper_verw(CPUX86State *env, target_ulong selector1)
2401 {
2402     uint32_t e1, e2, eflags, selector;
2403     int rpl, dpl, cpl;
2404 
2405     selector = selector1 & 0xffff;
2406     eflags = cpu_cc_compute_all(env) | CC_Z;
2407     if ((selector & 0xfffc) == 0) {
2408         goto fail;
2409     }
2410     if (load_segment_ra(env, &e1, &e2, selector, GETPC()) != 0) {
2411         goto fail;
2412     }
2413     if (!(e2 & DESC_S_MASK)) {
2414         goto fail;
2415     }
2416     rpl = selector & 3;
2417     dpl = (e2 >> DESC_DPL_SHIFT) & 3;
2418     cpl = env->hflags & HF_CPL_MASK;
2419     if (e2 & DESC_CS_MASK) {
2420         goto fail;
2421     } else {
2422         if (dpl < cpl || dpl < rpl) {
2423             goto fail;
2424         }
2425         if (!(e2 & DESC_W_MASK)) {
2426         fail:
2427             eflags &= ~CC_Z;
2428         }
2429     }
2430     CC_SRC = eflags;
2431     CC_OP = CC_OP_EFLAGS;
2432 }
2433