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7b414b4e | 1 | #/**@file\r |
2 | # Low leve x64 specific debug support functions.\r | |
3 | #\r | |
43a99f08 | 4 | # Copyright (c) 2006 - 2008, Intel Corporation\r |
7b414b4e | 5 | # All rights reserved. This program and the accompanying materials\r |
6 | # are licensed and made available under the terms and conditions of the BSD License\r | |
7 | # which accompanies this distribution. The full text of the license may be found at\r | |
8 | # http://opensource.org/licenses/bsd-license.php\r | |
9 | #\r | |
10 | # THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r | |
11 | # WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r | |
12 | #\r | |
43a99f08 | 13 | #**/ \r |
c1f23d63 | 14 | \r |
132f41f0 | 15 | ASM_GLOBAL ASM_PFX(OrigVector)\r |
16 | ASM_GLOBAL ASM_PFX(InterruptEntryStub)\r | |
17 | ASM_GLOBAL ASM_PFX(StubSize)\r | |
18 | ASM_GLOBAL ASM_PFX(CommonIdtEntry)\r | |
19 | ASM_GLOBAL ASM_PFX(FxStorSupport)\r | |
43a99f08 | 20 | \r |
21 | .data \r | |
c1f23d63 | 22 | \r |
43a99f08 | 23 | ASM_PFX(StubSize): .long ASM_PFX(InterruptEntryStubEnd) - ASM_PFX(InterruptEntryStub)\r |
24 | ASM_PFX(AppRsp): .long 0x11111111 # ?\r | |
25 | .long 0x11111111 # ?\r | |
26 | ASM_PFX(DebugRsp): .long 0x22222222 # ?\r | |
27 | .long 0x22222222 # ?\r | |
28 | ASM_PFX(ExtraPush): .long 0x33333333 # ?\r | |
29 | .long 0x33333333 # ?\r | |
30 | ASM_PFX(ExceptData): .long 0x44444444 # ?\r | |
31 | .long 0x44444444 # ?\r | |
32 | ASM_PFX(Rflags): .long 0x55555555 # ?\r | |
33 | .long 0x55555555 # ?\r | |
34 | ASM_PFX(OrigVector): .long 0x66666666 # ?\r | |
35 | .long 0x66666666 # ?\r | |
c1f23d63 | 36 | \r |
43a99f08 | 37 | ## The declarations below define the memory region that will be used for the debug stack.\r |
38 | ## The context record will be built by pushing register values onto this stack.\r | |
39 | ## It is imparitive that alignment be carefully managed, since the FXSTOR and\r | |
40 | ## FXRSTOR instructions will GP fault if their memory operand is not 16 byte aligned.\r | |
41 | ##\r | |
42 | ## The stub will switch stacks from the application stack to the debuger stack\r | |
43 | ## and pushes the exception number.\r | |
44 | ##\r | |
45 | ## Then we building the context record on the stack. Since the stack grows down,\r | |
46 | ## we push the fields of the context record from the back to the front. There\r | |
47 | ## are 336 bytes of stack used prior allocating the 512 bytes of stack to be\r | |
48 | ## used as the memory buffer for the fxstor instruction. Therefore address of\r | |
49 | ## the buffer used for the FXSTOR instruction is &Eax - 336 - 512, which\r | |
50 | ## must be 16 byte aligned.\r | |
51 | ##\r | |
52 | ## We carefully locate the stack to make this happen.\r | |
53 | ##\r | |
54 | ## For reference, the context structure looks like this:\r | |
55 | ## struct {\r | |
56 | ## UINT64 ExceptionData;\r | |
57 | ## FX_SAVE_STATE_X64 FxSaveState; // 512 bytes, must be 16 byte aligned\r | |
58 | ## UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;\r | |
59 | ## UINT64 Cr0, Cr1, Cr2, Cr3, Cr4, Cr8;\r | |
60 | ## UINT64 RFlags;\r | |
61 | ## UINT64 Ldtr, Tr;\r | |
62 | ## UINT64 Gdtr[2], Idtr[2];\r | |
63 | ## UINT64 Rip;\r | |
64 | ## UINT64 Gs, Fs, Es, Ds, Cs, Ss;\r | |
65 | ## UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;\r | |
66 | ## UINT64 R8, R9, R10, R11, R12, R13, R14, R15;\r | |
67 | ## } SYSTEM_CONTEXT_X64; // 64 bit system context record\r | |
68 | \r | |
69 | .align 16\r | |
70 | DebugStackEnd : .ascii "DbgStkEnd >>>>>>" # 16 byte long string - must be 16 bytes to preserve alignment\r | |
71 | .rept 0x1ffc\r | |
72 | .long 0x00000000 \r | |
73 | .endr\r | |
74 | # 32K should be enough stack\r | |
75 | # This allocation is coocked to insure\r | |
76 | # that the the buffer for the FXSTORE instruction\r | |
77 | # will be 16 byte aligned also.\r | |
78 | #\r | |
79 | ASM_PFX(ExceptionNumber): .long 0x77777777 # first entry will be the vector number pushed by the stub\r | |
80 | .long 0x77777777 # ?\r | |
81 | \r | |
82 | DebugStackBegin : .ascii "<<<< DbgStkBegin" # initial debug ESP == DebugStackBegin, set in stub\r | |
83 | \r | |
84 | \r | |
85 | .text\r | |
86 | \r | |
87 | #------------------------------------------------------------------------------\r | |
88 | # BOOLEAN\r | |
89 | # FxStorSupport (\r | |
90 | # void\r | |
91 | # )\r | |
92 | #\r | |
93 | # Abstract: Returns TRUE if FxStor instructions are supported\r | |
94 | #\r | |
132f41f0 | 95 | ASM_GLOBAL ASM_PFX(FxStorSupport)\r |
43a99f08 | 96 | ASM_PFX(FxStorSupport): \r |
97 | #\r | |
98 | # cpuid corrupts rbx which must be preserved per the C calling convention\r | |
99 | #\r | |
7b8c3785 | 100 | pushq %rbx\r |
101 | movq $1, %rax\r | |
43a99f08 | 102 | cpuid\r |
7b8c3785 | 103 | movl %edx, %eax\r |
104 | andq $0x01000000, %rax\r | |
105 | shrq $24, %rax\r | |
106 | popq %rbx\r | |
43a99f08 | 107 | ret\r |
108 | #------------------------------------------------------------------------------\r | |
109 | # void\r | |
110 | # Vect2Desc (\r | |
111 | # IA32_IDT_GATE_DESCRIPTOR * DestDesc, // rcx\r | |
112 | # void (*Vector) (void) // rdx\r | |
113 | # )\r | |
114 | #\r | |
115 | # Abstract: Encodes an IDT descriptor with the given physical address\r | |
116 | #\r | |
132f41f0 | 117 | ASM_GLOBAL ASM_PFX(Vect2Desc)\r |
43a99f08 | 118 | ASM_PFX(Vect2Desc):\r |
7b8c3785 | 119 | movq %rdx, %rax\r |
120 | movw %ax, (%rcx) # write bits 15..0 of offset\r | |
121 | movw %cs, %dx\r | |
122 | movw %dx, 2(%rcx) # SYS_CODE_SEL from GDT\r | |
123 | movw $(0x0e00 | 0x8000), 4(%rcx) # type = 386 interrupt gate, present\r | |
124 | shrq $16, %rax\r | |
125 | movw %ax, 6(%rcx) # write bits 31..16 of offset\r | |
126 | shrq $16, %rax\r | |
127 | movl %eax, 8(%rcx) # write bits 63..32 of offset\r | |
43a99f08 | 128 | \r |
129 | ret\r | |
130 | \r | |
131 | #------------------------------------------------------------------------------\r | |
132 | # InterruptEntryStub\r | |
133 | #\r | |
134 | # Abstract: This code is not a function, but is a small piece of code that is\r | |
135 | # copied and fixed up once for each IDT entry that is hooked.\r | |
136 | #\r | |
132f41f0 | 137 | ASM_GLOBAL ASM_PFX(InterruptEntryStub)\r |
43a99f08 | 138 | ASM_PFX(InterruptEntryStub):\r |
139 | \r | |
7b8c3785 | 140 | pushq $0 # push vector number - will be modified before installed\r |
43a99f08 | 141 | jmp ASM_PFX(CommonIdtEntry)\r |
142 | \r | |
132f41f0 | 143 | ASM_GLOBAL ASM_PFX(InterruptEntryStubEnd)\r |
43a99f08 | 144 | ASM_PFX(InterruptEntryStubEnd):\r |
c1f23d63 | 145 | \r |
43a99f08 | 146 | #------------------------------------------------------------------------------\r |
147 | # CommonIdtEntry\r | |
148 | #\r | |
149 | # Abstract: This code is not a function, but is the common part for all IDT\r | |
150 | # vectors.\r | |
151 | #\r | |
132f41f0 | 152 | ASM_GLOBAL ASM_PFX(CommonIdtEntry)\r |
43a99f08 | 153 | ##\r |
154 | ## At this point, the stub has saved the current application stack esp into AppRsp\r | |
155 | ## and switched stacks to the debug stack, where it pushed the vector number\r | |
156 | ##\r | |
157 | ## The application stack looks like this:\r | |
158 | ##\r | |
159 | ## ...\r | |
160 | ## (last application stack entry)\r | |
161 | ## [16 bytes alignment, do not care it]\r | |
162 | ## SS from interrupted task\r | |
163 | ## RSP from interrupted task\r | |
164 | ## rflags from interrupted task\r | |
165 | ## CS from interrupted task\r | |
166 | ## RIP from interrupted task\r | |
167 | ## Error code <-------------------- Only present for some exeption types\r | |
168 | ##\r | |
169 | ## Vector Number <----------------- pushed in our IDT Entry\r | |
170 | ##\r | |
171 | \r | |
172 | \r | |
173 | ## The stub switched us to the debug stack and pushed the interrupt number.\r | |
174 | ##\r | |
175 | ## Next, construct the context record. It will be build on the debug stack by\r | |
176 | ## pushing the registers in the correct order so as to create the context structure\r | |
177 | ## on the debug stack. The context record must be built from the end back to the\r | |
178 | ## beginning because the stack grows down...\r | |
179 | #\r | |
180 | ## For reference, the context record looks like this:\r | |
181 | ##\r | |
182 | ## typedef\r | |
183 | ## struct {\r | |
184 | ## UINT64 ExceptionData;\r | |
185 | ## FX_SAVE_STATE_X64 FxSaveState;\r | |
186 | ## UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;\r | |
187 | ## UINT64 Cr0, Cr2, Cr3, Cr4, Cr8;\r | |
188 | ## UINT64 RFlags;\r | |
189 | ## UINT64 Ldtr, Tr;\r | |
190 | ## UINT64 Gdtr[2], Idtr[2];\r | |
191 | ## UINT64 Rip;\r | |
192 | ## UINT64 Gs, Fs, Es, Ds, Cs, Ss;\r | |
193 | ## UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;\r | |
194 | ## UINT64 R8, R9, R10, R11, R12, R13, R14, R15;\r | |
195 | ## } SYSTEM_CONTEXT_X64; // 64\r | |
196 | ASM_PFX(CommonIdtEntry):\r | |
43a99f08 | 197 | ## NOTE: we save rsp here to prevent compiler put rip reference cause error AppRsp\r |
7b8c3785 | 198 | pushq %rax\r |
199 | movq (8)(%rsp), %rax # save vector number\r | |
200 | movq %rax, ASM_PFX(ExceptionNumber) # save vector number\r | |
201 | popq %rax\r | |
202 | addq $8, %rsp # pop vector number\r | |
203 | movq %rsp, ASM_PFX(AppRsp) # save stack top\r | |
204 | movq DebugStackBegin, %rsp # switch to debugger stack\r | |
205 | subq $8, %rsp # leave space for vector number\r | |
43a99f08 | 206 | ## UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;\r |
207 | ## UINT64 R8, R9, R10, R11, R12, R13, R14, R15;\r | |
7b8c3785 | 208 | pushq %r15\r |
209 | pushq %r14\r | |
210 | pushq %r13\r | |
211 | pushq %r12\r | |
212 | pushq %r11\r | |
213 | pushq %r10\r | |
214 | pushq %r9\r | |
215 | pushq %r8\r | |
216 | pushq %rax\r | |
217 | pushq %rcx\r | |
218 | pushq %rdx\r | |
219 | pushq %rbx\r | |
220 | pushq %rsp\r | |
221 | pushq %rbp\r | |
222 | pushq %rsi\r | |
223 | pushq %rdi\r | |
43a99f08 | 224 | ## Save interrupt state rflags register...\r |
225 | pushfq\r | |
7b8c3785 | 226 | popq %rax\r |
227 | movq %rax, ASM_PFX(Rflags)\r | |
43a99f08 | 228 | ## We need to determine if any extra data was pushed by the exception, and if so, save it\r |
229 | ## To do this, we check the exception number pushed by the stub, and cache the\r | |
230 | ## result in a variable since we'll need this again.\r | |
7b8c3785 | 231 | cmpl $0, ASM_PFX(ExceptionNumber)\r |
43a99f08 | 232 | jz ExtraPushOne\r |
7b8c3785 | 233 | cmpl $10, ASM_PFX(ExceptionNumber)\r |
43a99f08 | 234 | jz ExtraPushOne\r |
7b8c3785 | 235 | cmpl $11, ASM_PFX(ExceptionNumber)\r |
43a99f08 | 236 | jz ExtraPushOne\r |
7b8c3785 | 237 | cmpl $12, ASM_PFX(ExceptionNumber)\r |
43a99f08 | 238 | jz ExtraPushOne\r |
7b8c3785 | 239 | cmpl $13, ASM_PFX(ExceptionNumber)\r |
43a99f08 | 240 | jz ExtraPushOne\r |
7b8c3785 | 241 | cmpl $14, ASM_PFX(ExceptionNumber)\r |
43a99f08 | 242 | jz ExtraPushOne\r |
7b8c3785 | 243 | cmpl $17, ASM_PFX(ExceptionNumber)\r |
43a99f08 | 244 | jz ExtraPushOne\r |
7b8c3785 | 245 | movl $0, ASM_PFX(ExtraPush)\r |
246 | movl $0, ASM_PFX(ExceptData)\r | |
43a99f08 | 247 | jmp ExtraPushDone\r |
248 | ExtraPushOne:\r | |
7b8c3785 | 249 | movl $1, ASM_PFX(ExtraPush)\r |
43a99f08 | 250 | \r |
251 | ## If there's some extra data, save it also, and modify the saved AppRsp to effectively\r | |
252 | ## pop this value off the application's stack.\r | |
7b8c3785 | 253 | movq ASM_PFX(AppRsp), %rax \r |
254 | movq (%rax), %rbx\r | |
255 | movq %rbx, ASM_PFX(ExceptData)\r | |
256 | addq $8, %rax\r | |
257 | movq %rax, ASM_PFX(AppRsp)\r | |
43a99f08 | 258 | \r |
259 | ExtraPushDone:\r | |
260 | \r | |
261 | ## The "push" above pushed the debug stack rsp. Since what we're actually doing\r | |
262 | ## is building the context record on the debug stack, we need to save the pushed\r | |
263 | ## debug RSP, and replace it with the application's last stack entry...\r | |
7b8c3785 | 264 | movq 24(%rsp), %rax\r |
265 | movq %rax, ASM_PFX(DebugRsp)\r | |
266 | movq ASM_PFX(AppRsp), %rax \r | |
267 | addq $40, %rax\r | |
43a99f08 | 268 | # application stack has ss, rsp, rflags, cs, & rip, so\r |
509bc208 | 269 | # last actual application stack entry is 40 bytes\r |
270 | # into the application stack.\r | |
7b8c3785 | 271 | movq %rax, 24(%rsp)\r |
509bc208 | 272 | \r |
43a99f08 | 273 | ## continue building context record\r |
274 | ## UINT64 Gs, Fs, Es, Ds, Cs, Ss; insure high 16 bits of each is zero\r | |
7b8c3785 | 275 | movq %ss, %rax\r |
276 | pushq %rax\r | |
43a99f08 | 277 | # CS from application is one entry back in application stack\r |
7b8c3785 | 278 | movq ASM_PFX(AppRsp), %rax\r |
279 | movzxw 8(%rax), %rax\r | |
280 | pushq %rax\r | |
281 | \r | |
282 | movq %ds, %rax\r | |
283 | pushq %rax\r | |
284 | movq %es, %rax\r | |
285 | pushq %rax\r | |
286 | movq %fs, %rax\r | |
287 | pushq %rax\r | |
288 | movq %gs, %rax\r | |
289 | pushq %rax\r | |
43a99f08 | 290 | ## UINT64 Rip;\r |
291 | # Rip from application is on top of application stack\r | |
7b8c3785 | 292 | movq ASM_PFX(AppRsp), %rax \r |
293 | pushq (%rax)\r | |
43a99f08 | 294 | ## UINT64 Gdtr[2], Idtr[2];\r |
7b8c3785 | 295 | push $0\r |
296 | push $0\r | |
297 | sidtq (%rsp)\r | |
298 | push $0\r | |
299 | push $0\r | |
300 | sgdtq (%rsp)\r | |
43a99f08 | 301 | \r |
302 | ## UINT64 Ldtr, Tr;\r | |
7b8c3785 | 303 | xorq %rax, %rax\r |
304 | str %ax\r | |
305 | pushq %rax\r | |
306 | sldt %ax\r | |
307 | pushq %rax\r | |
43a99f08 | 308 | \r |
309 | ## UINT64 RFlags;\r | |
310 | ## Rflags from application is two entries back in application stack\r | |
7b8c3785 | 311 | movq ASM_PFX(AppRsp), %rax \r |
312 | pushq 16(%rax)\r | |
43a99f08 | 313 | ## UINT64 Cr0, Cr1, Cr2, Cr3, Cr4, Cr8;\r |
314 | ## insure FXSAVE/FXRSTOR is enabled in CR4...\r | |
315 | ## ... while we're at it, make sure DE is also enabled...\r | |
7b8c3785 | 316 | movq %cr8, %rax\r |
317 | pushq %rax\r | |
318 | movq %cr4, %rax\r | |
319 | orq $0x208, %rax\r | |
320 | movq %rax, %cr4\r | |
321 | pushq %rax\r | |
322 | movq %cr3, %rax\r | |
323 | pushq %rax\r | |
324 | movq %cr2, %rax\r | |
325 | pushq %rax\r | |
326 | push $0\r | |
327 | movq %cr0, %rax\r | |
328 | pushq %rax\r | |
43a99f08 | 329 | ## UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;\r |
7b8c3785 | 330 | movq %dr7, %rax\r |
331 | pushq %rax\r | |
43a99f08 | 332 | ## clear Dr7 while executing debugger itself\r |
7b8c3785 | 333 | xorq %rax, %rax\r |
334 | movq %rax, %dr7\r | |
43a99f08 | 335 | \r |
7b8c3785 | 336 | movq %dr6, %rax\r |
337 | pushq %rax\r | |
43a99f08 | 338 | ## insure all status bits in dr6 are clear...\r |
7b8c3785 | 339 | xorq %rax, %rax\r |
340 | movq %rax, %dr6\r | |
341 | \r | |
342 | movq %dr3, %rax\r | |
343 | pushq %rax\r | |
344 | movq %dr2, %rax\r | |
345 | pushq %rax\r | |
346 | movq %dr1, %rax\r | |
347 | pushq %rax\r | |
348 | movq %dr0, %rax\r | |
349 | pushq %rax\r | |
43a99f08 | 350 | \r |
351 | ## FX_SAVE_STATE_X64 FxSaveState;\r | |
7b8c3785 | 352 | subq $512, %rsp\r |
353 | movq %rsp, %rdi\r | |
43a99f08 | 354 | # IMPORTANT!! The debug stack has been carefully constructed to\r |
355 | # insure that rsp and rdi are 16 byte aligned when we get here.\r | |
356 | # They MUST be. If they are not, a GP fault will occur.\r | |
509bc208 | 357 | \r |
358 | # FXSTOR_RDI\r | |
7b8c3785 | 359 | fxsave (%rdi)\r |
43a99f08 | 360 | \r |
361 | ## UINT64 ExceptionData;\r | |
7b8c3785 | 362 | movq ASM_PFX(ExceptData), %rax\r |
363 | pushq %rax\r | |
509bc208 | 364 | \r |
43a99f08 | 365 | # call to C code which will in turn call registered handler\r |
366 | # pass in the vector number\r | |
7b8c3785 | 367 | movq %rsp, %rdx\r |
368 | movq ASM_PFX(ExceptionNumber), %rcx \r | |
369 | subq $40, %rsp\r | |
43a99f08 | 370 | call ASM_PFX(InterruptDistrubutionHub)\r |
7b8c3785 | 371 | addq $40, %rsp\r |
43a99f08 | 372 | # restore context...\r |
373 | ## UINT64 ExceptionData;\r | |
7b8c3785 | 374 | addq $8, %rsp\r |
509bc208 | 375 | \r |
43a99f08 | 376 | ## FX_SAVE_STATE_X64 FxSaveState;\r |
7b8c3785 | 377 | movq %rsp, %rsi\r |
509bc208 | 378 | \r |
379 | # FXRSTOR_RSI\r | |
7b8c3785 | 380 | fxrstor (%rsi)\r |
509bc208 | 381 | \r |
7b8c3785 | 382 | addq $512, %rsp\r |
509bc208 | 383 | \r |
384 | ## UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;\r | |
7b8c3785 | 385 | popq %rax\r |
386 | movq %rax, %dr0\r | |
387 | popq %rax\r | |
388 | movq %rax, %dr1\r | |
389 | popq %rax\r | |
390 | movq %rax, %dr2\r | |
391 | popq %rax\r | |
392 | movq %rax, %dr3\r | |
509bc208 | 393 | \r |
43a99f08 | 394 | ## skip restore of dr6. We cleared dr6 during the context save.\r |
7b8c3785 | 395 | addq $8, %rsp\r |
396 | popq %rax\r | |
397 | movq %rax, %dr7\r | |
509bc208 | 398 | \r |
43a99f08 | 399 | ## UINT64 Cr0, Cr1, Cr2, Cr3, Cr4, Cr8;\r |
7b8c3785 | 400 | popq %rax\r |
401 | movq %rax, %cr0\r | |
402 | addq $8, %rsp\r | |
403 | popq %rax\r | |
404 | movq %rax, %cr2\r | |
405 | popq %rax\r | |
406 | movq %rax, %cr3\r | |
407 | popq %rax\r | |
408 | movq %rax, %cr4\r | |
409 | popq %rax\r | |
410 | movq %rax, %cr8\r | |
43a99f08 | 411 | ## UINT64 RFlags;\r |
7b8c3785 | 412 | movq ASM_PFX(AppRsp), %rax \r |
413 | popq 16(%rax)\r | |
43a99f08 | 414 | ## UINT64 Ldtr, Tr;\r |
415 | ## UINT64 Gdtr[2], Idtr[2];\r | |
416 | ## Best not let anyone mess with these particular registers...\r | |
7b8c3785 | 417 | addq $48, %rsp\r |
43a99f08 | 418 | ## UINT64 Rip;\r |
7b8c3785 | 419 | popq (%rax)\r |
43a99f08 | 420 | \r |
421 | ## UINT64 Gs, Fs, Es, Ds, Cs, Ss;\r | |
422 | ## NOTE - modified segment registers could hang the debugger... We\r | |
423 | ## could attempt to insulate ourselves against this possibility,\r | |
424 | ## but that poses risks as well.\r | |
425 | ##\r | |
426 | \r | |
7b8c3785 | 427 | popq %rax\r |
428 | # movq %rax, %gs\r | |
429 | popq %rax\r | |
430 | # movq %rax, %fs\r | |
431 | popq %rax\r | |
432 | movq %rax, %es\r | |
433 | popq %rax\r | |
434 | movq %rax, %ds\r | |
435 | movq ASM_PFX(AppRsp), %rax \r | |
436 | popq 8(%rax)\r | |
437 | popq %rax\r | |
438 | movq %rax, %ss\r | |
43a99f08 | 439 | ## The next stuff to restore is the general purpose registers that were pushed\r |
440 | ## using the "push" instruction.\r | |
441 | ##\r | |
442 | ## The value of RSP as stored in the context record is the application RSP\r | |
443 | ## including the 5 entries on the application stack caused by the exception\r | |
444 | ## itself. It may have been modified by the debug agent, so we need to\r | |
445 | ## determine if we need to relocate the application stack.\r | |
446 | \r | |
7b8c3785 | 447 | movq 24(%rsp), %rbx # move the potentially modified AppRsp into rbx\r |
448 | movq ASM_PFX(AppRsp), %rax \r | |
449 | addq $40, %rax\r | |
450 | cmpq %rax, %rbx\r | |
43a99f08 | 451 | je NoAppStackMove\r |
452 | \r | |
7b8c3785 | 453 | movq ASM_PFX(AppRsp), %rax \r |
454 | movq (%rax), %rcx # RIP\r | |
455 | movq %rcx, (%rbx)\r | |
43a99f08 | 456 | \r |
7b8c3785 | 457 | movq 8(%rax), %rcx # CS\r |
458 | movq %rcx, 8(%rbx)\r | |
43a99f08 | 459 | \r |
7b8c3785 | 460 | movq 16(%rax), %rcx # RFLAGS\r |
461 | movq %rcx, 16(%rbx)\r | |
43a99f08 | 462 | \r |
7b8c3785 | 463 | movq 24(%rax), %rcx # RSP\r |
464 | movq %rcx, 24(%rbx)\r | |
43a99f08 | 465 | \r |
7b8c3785 | 466 | movq 32(%rax), %rcx # SS\r |
467 | movq %rcx, 32(%rbx)\r | |
43a99f08 | 468 | \r |
7b8c3785 | 469 | movq %rbx, %rax # modify the saved AppRsp to the new AppRsp\r |
470 | movq %rax, ASM_PFX(AppRsp)\r | |
43a99f08 | 471 | NoAppStackMove:\r |
7b8c3785 | 472 | movq ASM_PFX(DebugRsp), %rax # restore the DebugRsp on the debug stack\r |
43a99f08 | 473 | # so our "pop" will not cause a stack switch\r |
7b8c3785 | 474 | movq %rax, 24(%rsp)\r |
43a99f08 | 475 | \r |
7b8c3785 | 476 | cmpl $0x068, ASM_PFX(ExceptionNumber)\r |
43a99f08 | 477 | jne NoChain\r |
478 | \r | |
479 | Chain:\r | |
480 | \r | |
481 | ## Restore rflags so when we chain, the flags will be exactly as if we were never here.\r | |
482 | ## We gin up the stack to do an iretq so we can get ALL the flags.\r | |
7b8c3785 | 483 | movq ASM_PFX(AppRsp), %rax \r |
484 | movq 40(%rax), %rbx\r | |
485 | pushq %rbx\r | |
486 | movq %ss, %rax\r | |
487 | pushq %rax\r | |
488 | movq %rsp, %rax\r | |
489 | addq $16, %rax\r | |
490 | pushq %rax\r | |
491 | movq ASM_PFX(AppRsp), %rax \r | |
492 | movq 16(%rax), %rbx\r | |
493 | andq $0xfffffffffffffcff, %rbx # special handling for IF and TF\r | |
494 | pushq %rbx\r | |
495 | movq %cs, %rax\r | |
496 | pushq %rax\r | |
497 | movq PhonyIretq, %rax \r | |
498 | pushq %rax\r | |
43a99f08 | 499 | iretq\r |
500 | PhonyIretq:\r | |
501 | \r | |
502 | ## UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;\r | |
503 | ## UINT64 R8, R9, R10, R11, R12, R13, R14, R15;\r | |
7b8c3785 | 504 | popq %rdi\r |
505 | popq %rsi\r | |
506 | popq %rbp\r | |
507 | popq %rsp\r | |
508 | popq %rbx\r | |
509 | popq %rdx\r | |
510 | popq %rcx\r | |
511 | popq %rax\r | |
512 | popq %r8\r | |
513 | popq %r9\r | |
514 | popq %r10\r | |
515 | popq %r11\r | |
516 | popq %r12\r | |
517 | popq %r13\r | |
518 | popq %r14\r | |
519 | popq %r15\r | |
43a99f08 | 520 | \r |
521 | ## Switch back to application stack\r | |
7b8c3785 | 522 | movq ASM_PFX(AppRsp), %rsp \r |
43a99f08 | 523 | ## Jump to original handler\r |
524 | jmp ASM_PFX(OrigVector)\r | |
525 | NoChain:\r | |
526 | ## UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;\r | |
527 | ## UINT64 R8, R9, R10, R11, R12, R13, R14, R15;\r | |
7b8c3785 | 528 | popq %rdi\r |
529 | popq %rsi\r | |
530 | popq %rbp\r | |
531 | popq %rsp\r | |
532 | popq %rbx\r | |
533 | popq %rdx\r | |
534 | popq %rcx\r | |
535 | popq %rax\r | |
536 | popq %r8\r | |
537 | popq %r9\r | |
538 | popq %r10\r | |
539 | popq %r11\r | |
540 | popq %r12\r | |
541 | popq %r13\r | |
542 | popq %r14\r | |
543 | popq %r15\r | |
43a99f08 | 544 | \r |
545 | ## Switch back to application stack\r | |
7b8c3785 | 546 | movq ASM_PFX(AppRsp), %rsp \r |
43a99f08 | 547 | \r |
548 | ## We're outa here...\r | |
549 | iret\r |