1
2 /*--------------------------------------------------------------------*/
3 /*--- Darwin-specific syscalls, etc. syswrap-amd64-darwin.c ---*/
4 /*--------------------------------------------------------------------*/
5
6 /*
7 This file is part of Valgrind, a dynamic binary instrumentation
8 framework.
9
10 Copyright (C) 2005-2017 Apple Inc.
11 Greg Parker gparker@apple.com
12
13 This program is free software; you can redistribute it and/or
14 modify it under the terms of the GNU General Public License as
15 published by the Free Software Foundation; either version 2 of the
16 License, or (at your option) any later version.
17
18 This program is distributed in the hope that it will be useful, but
19 WITHOUT ANY WARRANTY; without even the implied warranty of
20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 General Public License for more details.
22
23 You should have received a copy of the GNU General Public License
24 along with this program; if not, write to the Free Software
25 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
26 02111-1307, USA.
27
28 The GNU General Public License is contained in the file COPYING.
29 */
30
31 #if defined(VGP_amd64_darwin)
32
33 #include "config.h" // DARWIN_VERS
34 #include "pub_core_basics.h"
35 #include "pub_core_vki.h"
36 #include "pub_core_threadstate.h"
37 #include "pub_core_aspacemgr.h"
38 #include "pub_core_xarray.h"
39 #include "pub_core_clientstate.h"
40 #include "pub_core_debuglog.h"
41 #include "pub_core_debuginfo.h" // VG_(di_notify_*)
42 #include "pub_core_transtab.h" // VG_(discard_translations)
43 #include "pub_core_libcbase.h"
44 #include "pub_core_libcassert.h"
45 #include "pub_core_libcfile.h"
46 #include "pub_core_libcprint.h"
47 #include "pub_core_libcproc.h"
48 #include "pub_core_libcsignal.h"
49 #include "pub_core_mallocfree.h"
50 #include "pub_core_options.h"
51 #include "pub_core_scheduler.h"
52 #include "pub_core_sigframe.h" // For VG_(sigframe_destroy)()
53 #include "pub_core_signals.h"
54 #include "pub_core_syscall.h"
55 #include "pub_core_syswrap.h"
56 #include "pub_core_tooliface.h"
57
58 #include "priv_types_n_macros.h"
59 #include "priv_syswrap-generic.h" /* for decls of generic wrappers */
60 #include "priv_syswrap-darwin.h" /* for decls of darwin-ish wrappers */
61 #include "priv_syswrap-main.h"
62
63
64 #include <mach/mach.h>
65
x86_thread_state64_from_vex(x86_thread_state64_t * mach,VexGuestAMD64State * vex)66 static void x86_thread_state64_from_vex(x86_thread_state64_t *mach,
67 VexGuestAMD64State *vex)
68 {
69 mach->__rax = vex->guest_RAX;
70 mach->__rbx = vex->guest_RBX;
71 mach->__rcx = vex->guest_RCX;
72 mach->__rdx = vex->guest_RDX;
73 mach->__rdi = vex->guest_RDI;
74 mach->__rsi = vex->guest_RSI;
75 mach->__rbp = vex->guest_RBP;
76 mach->__rsp = vex->guest_RSP;
77 mach->__rflags = LibVEX_GuestAMD64_get_rflags(vex);
78 mach->__rip = vex->guest_RIP;
79 mach->__r8 = vex->guest_R8;
80 mach->__r9 = vex->guest_R9;
81 mach->__r10 = vex->guest_R10;
82 mach->__r11 = vex->guest_R11;
83 mach->__r12 = vex->guest_R12;
84 mach->__r13 = vex->guest_R13;
85 mach->__r14 = vex->guest_R14;
86 mach->__r15 = vex->guest_R15;
87 /* GrP fixme
88 mach->__cs = vex->guest_CS;
89 mach->__fs = vex->guest_FS;
90 mach->__gs = vex->guest_GS;
91 */
92 }
93
94
x86_float_state64_from_vex(x86_float_state64_t * mach,VexGuestAMD64State * vex)95 static void x86_float_state64_from_vex(x86_float_state64_t *mach,
96 VexGuestAMD64State *vex)
97 {
98 // DDD: #warning GrP fixme fp state
99 // JRS: what about the YMMHI bits? Are they important?
100 VG_(memcpy)(&mach->__fpu_xmm0, &vex->guest_YMM0, sizeof(mach->__fpu_xmm0));
101 VG_(memcpy)(&mach->__fpu_xmm1, &vex->guest_YMM1, sizeof(mach->__fpu_xmm1));
102 VG_(memcpy)(&mach->__fpu_xmm2, &vex->guest_YMM2, sizeof(mach->__fpu_xmm2));
103 VG_(memcpy)(&mach->__fpu_xmm3, &vex->guest_YMM3, sizeof(mach->__fpu_xmm3));
104 VG_(memcpy)(&mach->__fpu_xmm4, &vex->guest_YMM4, sizeof(mach->__fpu_xmm4));
105 VG_(memcpy)(&mach->__fpu_xmm5, &vex->guest_YMM5, sizeof(mach->__fpu_xmm5));
106 VG_(memcpy)(&mach->__fpu_xmm6, &vex->guest_YMM6, sizeof(mach->__fpu_xmm6));
107 VG_(memcpy)(&mach->__fpu_xmm7, &vex->guest_YMM7, sizeof(mach->__fpu_xmm7));
108 VG_(memcpy)(&mach->__fpu_xmm8, &vex->guest_YMM8, sizeof(mach->__fpu_xmm8));
109 VG_(memcpy)(&mach->__fpu_xmm9, &vex->guest_YMM9, sizeof(mach->__fpu_xmm9));
110 VG_(memcpy)(&mach->__fpu_xmm10, &vex->guest_YMM10, sizeof(mach->__fpu_xmm10));
111 VG_(memcpy)(&mach->__fpu_xmm11, &vex->guest_YMM11, sizeof(mach->__fpu_xmm11));
112 VG_(memcpy)(&mach->__fpu_xmm12, &vex->guest_YMM12, sizeof(mach->__fpu_xmm12));
113 VG_(memcpy)(&mach->__fpu_xmm13, &vex->guest_YMM13, sizeof(mach->__fpu_xmm13));
114 VG_(memcpy)(&mach->__fpu_xmm14, &vex->guest_YMM14, sizeof(mach->__fpu_xmm14));
115 VG_(memcpy)(&mach->__fpu_xmm15, &vex->guest_YMM15, sizeof(mach->__fpu_xmm15));
116 }
117
118
thread_state_from_vex(thread_state_t mach_generic,thread_state_flavor_t flavor,mach_msg_type_number_t count,VexGuestArchState * vex_generic)119 void thread_state_from_vex(thread_state_t mach_generic,
120 thread_state_flavor_t flavor,
121 mach_msg_type_number_t count,
122 VexGuestArchState *vex_generic)
123 {
124 VexGuestAMD64State *vex = (VexGuestAMD64State *)vex_generic;
125
126 switch (flavor) {
127 case x86_THREAD_STATE64:
128 vg_assert(count == x86_THREAD_STATE64_COUNT);
129 x86_thread_state64_from_vex((x86_thread_state64_t *)mach_generic, vex);
130 break;
131
132 case x86_FLOAT_STATE64:
133 vg_assert(count == x86_FLOAT_STATE64_COUNT);
134 x86_float_state64_from_vex((x86_float_state64_t *)mach_generic, vex);
135 break;
136
137 case x86_THREAD_STATE:
138 ((x86_float_state_t *)mach_generic)->fsh.flavor = flavor;
139 ((x86_float_state_t *)mach_generic)->fsh.count = count;
140 x86_thread_state64_from_vex(&((x86_thread_state_t *)mach_generic)->uts.ts64, vex);
141 break;
142
143 case x86_FLOAT_STATE:
144 ((x86_float_state_t *)mach_generic)->fsh.flavor = flavor;
145 ((x86_float_state_t *)mach_generic)->fsh.count = count;
146 x86_float_state64_from_vex(&((x86_float_state_t *)mach_generic)->ufs.fs64, vex);
147 break;
148
149 case x86_EXCEPTION_STATE:
150 VG_(printf)("thread_state_from_vex: TODO, want exception state\n");
151 vg_assert(0);
152
153 default:
154 VG_(printf)("thread_state_from_vex: flavor:%#x\n", flavor);
155 vg_assert(0);
156 }
157 }
158
159
x86_thread_state64_to_vex(const x86_thread_state64_t * mach,VexGuestAMD64State * vex)160 static void x86_thread_state64_to_vex(const x86_thread_state64_t *mach,
161 VexGuestAMD64State *vex)
162 {
163 LibVEX_GuestAMD64_initialise(vex);
164 vex->guest_RAX = mach->__rax;
165 vex->guest_RBX = mach->__rbx;
166 vex->guest_RCX = mach->__rcx;
167 vex->guest_RDX = mach->__rdx;
168 vex->guest_RDI = mach->__rdi;
169 vex->guest_RSI = mach->__rsi;
170 vex->guest_RBP = mach->__rbp;
171 vex->guest_RSP = mach->__rsp;
172 // DDD: #warning GrP fixme eflags
173 vex->guest_RIP = mach->__rip;
174 vex->guest_R8 = mach->__r8;
175 vex->guest_R9 = mach->__r9;
176 vex->guest_R10 = mach->__r10;
177 vex->guest_R11 = mach->__r11;
178 vex->guest_R12 = mach->__r12;
179 vex->guest_R13 = mach->__r13;
180 vex->guest_R14 = mach->__r14;
181 vex->guest_R15 = mach->__r15;
182 /* GrP fixme
183 vex->guest_CS = mach->__cs;
184 vex->guest_FS = mach->__fs;
185 vex->guest_GS = mach->__gs;
186 */
187 }
188
x86_float_state64_to_vex(const x86_float_state64_t * mach,VexGuestAMD64State * vex)189 static void x86_float_state64_to_vex(const x86_float_state64_t *mach,
190 VexGuestAMD64State *vex)
191 {
192 // DDD: #warning GrP fixme fp state
193 // JRS: what about the YMMHI bits? Are they important?
194 VG_(memcpy)(&vex->guest_YMM0, &mach->__fpu_xmm0, sizeof(mach->__fpu_xmm0));
195 VG_(memcpy)(&vex->guest_YMM1, &mach->__fpu_xmm1, sizeof(mach->__fpu_xmm1));
196 VG_(memcpy)(&vex->guest_YMM2, &mach->__fpu_xmm2, sizeof(mach->__fpu_xmm2));
197 VG_(memcpy)(&vex->guest_YMM3, &mach->__fpu_xmm3, sizeof(mach->__fpu_xmm3));
198 VG_(memcpy)(&vex->guest_YMM4, &mach->__fpu_xmm4, sizeof(mach->__fpu_xmm4));
199 VG_(memcpy)(&vex->guest_YMM5, &mach->__fpu_xmm5, sizeof(mach->__fpu_xmm5));
200 VG_(memcpy)(&vex->guest_YMM6, &mach->__fpu_xmm6, sizeof(mach->__fpu_xmm6));
201 VG_(memcpy)(&vex->guest_YMM7, &mach->__fpu_xmm7, sizeof(mach->__fpu_xmm7));
202 VG_(memcpy)(&vex->guest_YMM8, &mach->__fpu_xmm8, sizeof(mach->__fpu_xmm8));
203 VG_(memcpy)(&vex->guest_YMM9, &mach->__fpu_xmm9, sizeof(mach->__fpu_xmm9));
204 VG_(memcpy)(&vex->guest_YMM10, &mach->__fpu_xmm10, sizeof(mach->__fpu_xmm10));
205 VG_(memcpy)(&vex->guest_YMM11, &mach->__fpu_xmm11, sizeof(mach->__fpu_xmm11));
206 VG_(memcpy)(&vex->guest_YMM12, &mach->__fpu_xmm12, sizeof(mach->__fpu_xmm12));
207 VG_(memcpy)(&vex->guest_YMM13, &mach->__fpu_xmm13, sizeof(mach->__fpu_xmm13));
208 VG_(memcpy)(&vex->guest_YMM14, &mach->__fpu_xmm14, sizeof(mach->__fpu_xmm14));
209 VG_(memcpy)(&vex->guest_YMM15, &mach->__fpu_xmm15, sizeof(mach->__fpu_xmm15));
210 }
211
212
thread_state_to_vex(const thread_state_t mach_generic,thread_state_flavor_t flavor,mach_msg_type_number_t count,VexGuestArchState * vex_generic)213 void thread_state_to_vex(const thread_state_t mach_generic,
214 thread_state_flavor_t flavor,
215 mach_msg_type_number_t count,
216 VexGuestArchState *vex_generic)
217 {
218 VexGuestAMD64State *vex = (VexGuestAMD64State *)vex_generic;
219
220 switch(flavor) {
221 case x86_THREAD_STATE64:
222 vg_assert(count == x86_THREAD_STATE64_COUNT);
223 x86_thread_state64_to_vex((const x86_thread_state64_t*)mach_generic,vex);
224 break;
225 case x86_FLOAT_STATE64:
226 vg_assert(count == x86_FLOAT_STATE64_COUNT);
227 x86_float_state64_to_vex((const x86_float_state64_t*)mach_generic,vex);
228 break;
229
230 default:
231 vg_assert(0);
232 break;
233 }
234 }
235
236
build_thread(const thread_state_t state,thread_state_flavor_t flavor,mach_msg_type_number_t count)237 ThreadState *build_thread(const thread_state_t state,
238 thread_state_flavor_t flavor,
239 mach_msg_type_number_t count)
240 {
241 ThreadId tid = VG_(alloc_ThreadState)();
242 ThreadState *tst = VG_(get_ThreadState)(tid);
243
244 vg_assert(flavor == x86_THREAD_STATE64);
245 vg_assert(count == x86_THREAD_STATE64_COUNT);
246
247 // Initialize machine registers
248
249 thread_state_to_vex(state, flavor, count, &tst->arch.vex);
250
251 I_die_here;
252 // GrP fixme signals, sig_mask, tmp_sig_mask, os_state.parent
253
254 find_stack_segment(tid, tst->arch.vex.guest_RSP);
255
256 return tst;
257 }
258
259
260 // Edit the thread state to send to the real kernel.
261 // The real thread will run start_thread_NORETURN(tst)
262 // on a separate non-client stack.
hijack_thread_state(thread_state_t mach_generic,thread_state_flavor_t flavor,mach_msg_type_number_t count,ThreadState * tst)263 void hijack_thread_state(thread_state_t mach_generic,
264 thread_state_flavor_t flavor,
265 mach_msg_type_number_t count,
266 ThreadState *tst)
267 {
268 x86_thread_state64_t *mach = (x86_thread_state64_t *)mach_generic;
269 char *stack;
270
271 vg_assert(flavor == x86_THREAD_STATE64);
272 vg_assert(count == x86_THREAD_STATE64_COUNT);
273
274 stack = (char *)allocstack(tst->tid);
275 stack -= 64+320; // make room for top frame
276 memset(stack, 0, 64+320); // ...and clear it
277 *(uintptr_t *)stack = 0; // push fake return address
278
279 mach->__rdi = (uintptr_t)tst; // arg1 = tst
280 mach->__rip = (uintptr_t)&start_thread_NORETURN;
281 mach->__rsp = (uintptr_t)stack;
282 }
283
284
285 /* Call f(arg1), but first switch stacks, using 'stack' as the new
286 stack, and use 'retaddr' as f's return-to address. Also, clear all
287 the integer registers before entering f.*/
288 __attribute__((noreturn))
289 void call_on_new_stack_0_1 ( Addr stack,
290 Addr retaddr,
291 void (*f)(Word),
292 Word arg1 );
293 // %rdi == stack (must be 16-byte aligned)
294 // %rsi == retaddr
295 // %rdx == f
296 // %rcx == arg1
297 asm(
298 ".globl _call_on_new_stack_0_1\n"
299 "_call_on_new_stack_0_1:\n"
300 " movq %rsp, %rbp\n" // remember old stack pointer
301 " movq %rdi, %rsp\n" // set new stack
302 " movq %rcx, %rdi\n" // set arg1
303 " pushq %rsi\n" // retaddr to new stack
304 " pushq %rdx\n" // f to new stack
305 " movq $0, %rax\n" // zero all other GP regs
306 " movq $0, %rbx\n"
307 " movq $0, %rcx\n"
308 " movq $0, %rdx\n"
309 " movq $0, %rsi\n"
310 " movq $0, %rbp\n"
311 " movq $0, %r8\n"
312 " movq $0, %r9\n"
313 " movq $0, %r10\n"
314 " movq $0, %r11\n"
315 " movq $0, %r12\n"
316 " movq $0, %r13\n"
317 " movq $0, %r14\n"
318 " movq $0, %r15\n"
319 " ret\n" // jump to f
320 " ud2\n" // should never get here
321 );
322
323 asm(
324 ".globl _pthread_hijack_asm\n"
325 "_pthread_hijack_asm:\n"
326 " movq %rsp,%rbp\n"
327 " push $0\n" // alignment pad
328 " push %rbp\n" // original sp
329 // other values stay where they are in registers
330 " push $0\n" // fake return address
331 " jmp _pthread_hijack\n"
332 );
333
334
335
pthread_hijack(Addr self,Addr kport,Addr func,Addr func_arg,Addr stacksize,Addr flags,Addr sp)336 void pthread_hijack(Addr self, Addr kport, Addr func, Addr func_arg,
337 Addr stacksize, Addr flags, Addr sp)
338 {
339 vki_sigset_t blockall;
340 ThreadState *tst = (ThreadState *)func_arg;
341 VexGuestAMD64State *vex = &tst->arch.vex;
342
343 // VG_(printf)("pthread_hijack pthread %p, machthread %p, func %p, arg %p, stack %p, flags %p, stack %p\n", self, kport, func, func_arg, stacksize, flags, sp);
344
345 // Wait for parent thread's permission.
346 // The parent thread holds V's lock on our behalf.
347 semaphore_wait(tst->os_state.child_go);
348
349 /* Start the thread with all signals blocked. VG_(scheduler) will
350 set the mask correctly when we finally get there. */
351 VG_(sigfillset)(&blockall);
352 VG_(sigprocmask)(VKI_SIG_SETMASK, &blockall, NULL);
353
354 // Set thread's registers
355 // Do this FIRST because some code below tries to collect a backtrace,
356 // which requires valid register data.
357 LibVEX_GuestAMD64_initialise(vex);
358 vex->guest_RIP = pthread_starter;
359 vex->guest_RDI = self;
360 vex->guest_RSI = kport;
361 vex->guest_RDX = func;
362 vex->guest_RCX = tst->os_state.func_arg;
363 vex->guest_R8 = stacksize;
364 vex->guest_R9 = flags;
365 vex->guest_RSP = sp;
366
367 // Record thread's stack and Mach port and pthread struct
368 tst->os_state.pthread = self;
369 tst->os_state.lwpid = kport;
370 record_named_port(tst->tid, kport, MACH_PORT_RIGHT_SEND, "thread-%p");
371
372 if ((flags & 0x01000000) == 0) {
373 // kernel allocated stack - needs mapping
374 Addr stack = VG_PGROUNDUP(sp) - stacksize;
375 tst->client_stack_highest_byte = stack+stacksize-1;
376 tst->client_stack_szB = stacksize;
377
378 // pthread structure
379 ML_(notify_core_and_tool_of_mmap)(
380 stack+stacksize, pthread_structsize,
381 VKI_PROT_READ|VKI_PROT_WRITE, VKI_MAP_PRIVATE, -1, 0);
382 // stack contents
383 ML_(notify_core_and_tool_of_mmap)(
384 stack, stacksize,
385 VKI_PROT_READ|VKI_PROT_WRITE, VKI_MAP_PRIVATE, -1, 0);
386 // guard page
387 ML_(notify_core_and_tool_of_mmap)(
388 stack-VKI_PAGE_SIZE, VKI_PAGE_SIZE,
389 0, VKI_MAP_PRIVATE, -1, 0);
390 } else {
391 // client allocated stack
392 find_stack_segment(tst->tid, sp);
393 }
394 ML_(sync_mappings)("after", "pthread_hijack", 0);
395
396 // DDD: should this be here rather than in POST(sys_bsdthread_create)?
397 // But we don't have ptid here...
398 //VG_TRACK ( pre_thread_ll_create, ptid, tst->tid );
399
400 // Tell parent thread's POST(sys_bsdthread_create) that we're done
401 // initializing registers and mapping memory.
402 semaphore_signal(tst->os_state.child_done);
403 // LOCK IS GONE BELOW THIS POINT
404
405 // Go!
406 call_on_new_stack_0_1(tst->os_state.valgrind_stack_init_SP, 0,
407 start_thread_NORETURN, (Word)tst);
408
409 /*NOTREACHED*/
410 vg_assert(0);
411 }
412
413
414
415 asm(
416 ".globl _wqthread_hijack_asm\n"
417 "_wqthread_hijack_asm:\n"
418 " movq %rsp,%r9\n" // original sp
419 // other values stay where they are in registers
420 " push $0\n" // fake return address
421 " jmp _wqthread_hijack\n"
422 );
423
424
425 /* wqthread note: The kernel may create or destroy pthreads in the
426 wqthread pool at any time with no userspace interaction,
427 and wqthread_start may be entered at any time with no userspace
428 interaction.
429 To handle this in valgrind, we create and destroy a valgrind
430 thread for every work item.
431 */
wqthread_hijack(Addr self,Addr kport,Addr stackaddr,Addr workitem,Int reuse,Addr sp)432 void wqthread_hijack(Addr self, Addr kport, Addr stackaddr, Addr workitem,
433 Int reuse, Addr sp)
434 {
435 ThreadState *tst;
436 VexGuestAMD64State *vex;
437 Addr stack;
438 SizeT stacksize;
439 vki_sigset_t blockall;
440
441 /* When we enter here we hold no lock (!), so we better acquire it
442 pronto. Why do we hold no lock? Because (presumably) the only
443 way to get here is as a result of a SfMayBlock syscall
444 "workq_ops(WQOPS_THREAD_RETURN)", which will have dropped the
445 lock. At least that's clear for the 'reuse' case. The
446 non-reuse case? Dunno, perhaps it's a new thread the kernel
447 pulled out of a hat. In any case we still need to take a
448 lock. */
449 VG_(acquire_BigLock_LL)("wqthread_hijack");
450
451 if (0) VG_(printf)(
452 "wqthread_hijack: self %#lx, kport %#lx, "
453 "stackaddr %#lx, workitem %#lx, reuse/flags %x, sp %#lx\n",
454 self, kport, stackaddr, workitem, (UInt)reuse, sp);
455
456 /* Start the thread with all signals blocked. VG_(scheduler) will
457 set the mask correctly when we finally get there. */
458 VG_(sigfillset)(&blockall);
459 VG_(sigprocmask)(VKI_SIG_SETMASK, &blockall, NULL);
460
461 /* For 10.7 and earlier, |reuse| appeared to be used as a simple
462 boolean. In 10.8 and later its name changed to |flags| and has
463 various other bits OR-d into it too, so it's necessary to fish
464 out just the relevant parts. Hence: */
465 # if DARWIN_VERS <= DARWIN_10_7
466 Bool is_reuse = reuse != 0;
467 # elif DARWIN_VERS > DARWIN_10_7
468 Bool is_reuse = (reuse & 0x20000 /* == WQ_FLAG_THREAD_REUSE */) != 0;
469 # else
470 # error "Unsupported Darwin version"
471 # endif
472
473 if (is_reuse) {
474
475 /* For whatever reason, tst->os_state.pthread appear to have a
476 constant offset of 96 on 10.7, but zero on 10.6 and 10.5. No
477 idea why. */
478 # if DARWIN_VERS <= DARWIN_10_6
479 UWord magic_delta = 0;
480 # elif DARWIN_VERS == DARWIN_10_7 || DARWIN_VERS == DARWIN_10_8
481 UWord magic_delta = 0x60;
482 # elif DARWIN_VERS == DARWIN_10_9 \
483 || DARWIN_VERS == DARWIN_10_10 \
484 || DARWIN_VERS == DARWIN_10_11 \
485 || DARWIN_VERS == DARWIN_10_12 \
486 || DARWIN_VERS == DARWIN_10_13
487 UWord magic_delta = 0xE0;
488 # else
489 # error "magic_delta: to be computed on new OS version"
490 // magic_delta = tst->os_state.pthread - self
491 # endif
492
493 // This thread already exists; we're merely re-entering
494 // after leaving via workq_ops(WQOPS_THREAD_RETURN).
495 // Don't allocate any V thread resources.
496 // Do reset thread registers.
497 ThreadId tid = VG_(lwpid_to_vgtid)(kport);
498 vg_assert(VG_(is_valid_tid)(tid));
499 vg_assert(mach_thread_self() == kport);
500
501 tst = VG_(get_ThreadState)(tid);
502
503 if (0) VG_(printf)("wqthread_hijack reuse %s: tid %u, tst %p, "
504 "tst->os_state.pthread %#lx, self %#lx\n",
505 tst->os_state.pthread == self ? "SAME" : "DIFF",
506 tid, (void *)tst, tst->os_state.pthread, self);
507
508 vex = &tst->arch.vex;
509 vg_assert(tst->os_state.pthread - magic_delta == self);
510 }
511 else {
512 // This is a new thread.
513 tst = VG_(get_ThreadState)(VG_(alloc_ThreadState)());
514 vex = &tst->arch.vex;
515 allocstack(tst->tid);
516 LibVEX_GuestAMD64_initialise(vex);
517 }
518
519 // Set thread's registers
520 // Do this FIRST because some code below tries to collect a backtrace,
521 // which requires valid register data.
522 vex->guest_RIP = wqthread_starter;
523 vex->guest_RDI = self;
524 vex->guest_RSI = kport;
525 vex->guest_RDX = stackaddr;
526 vex->guest_RCX = workitem;
527 vex->guest_R8 = reuse;
528 vex->guest_R9 = 0;
529 vex->guest_RSP = sp;
530
531 stacksize = 512*1024; // wq stacks are always DEFAULT_STACK_SIZE
532 stack = VG_PGROUNDUP(sp) - stacksize;
533
534 if (is_reuse) {
535 // Continue V's thread back in the scheduler.
536 // The client thread is of course in another location entirely.
537
538 /* Drop the lock before going into
539 ML_(wqthread_continue_NORETURN). The latter will immediately
540 attempt to reacquire it in non-LL mode, which is a bit
541 wasteful but I don't think is harmful. A better solution
542 would be to not drop the lock but instead "upgrade" it from a
543 LL lock to a full lock, but that's too much like hard work
544 right now. */
545 VG_(release_BigLock_LL)("wqthread_hijack(1)");
546 ML_(wqthread_continue_NORETURN)(tst->tid);
547 }
548 else {
549 // Record thread's stack and Mach port and pthread struct
550 tst->os_state.pthread = self;
551 tst->os_state.lwpid = kport;
552 record_named_port(tst->tid, kport, MACH_PORT_RIGHT_SEND, "wqthread-%p");
553
554 // kernel allocated stack - needs mapping
555 tst->client_stack_highest_byte = stack+stacksize-1;
556 tst->client_stack_szB = stacksize;
557
558 // GrP fixme scheduler lock?!
559
560 // pthread structure
561 ML_(notify_core_and_tool_of_mmap)(
562 stack+stacksize, pthread_structsize,
563 VKI_PROT_READ|VKI_PROT_WRITE, VKI_MAP_PRIVATE, -1, 0);
564 // stack contents
565 // GrP fixme uninitialized!
566 ML_(notify_core_and_tool_of_mmap)(
567 stack, stacksize,
568 VKI_PROT_READ|VKI_PROT_WRITE, VKI_MAP_PRIVATE, -1, 0);
569 // guard page
570 // GrP fixme ban_mem_stack!
571 ML_(notify_core_and_tool_of_mmap)(
572 stack-VKI_PAGE_SIZE, VKI_PAGE_SIZE,
573 0, VKI_MAP_PRIVATE, -1, 0);
574
575 ML_(sync_mappings)("after", "wqthread_hijack", 0);
576
577 // Go!
578 /* Same comments as the 'release' in the then-clause.
579 start_thread_NORETURN calls run_thread_NORETURN calls
580 thread_wrapper which acquires the lock before continuing.
581 Let's hope nothing non-thread-local happens until that point.
582
583 DDD: I think this is plain wrong .. if we get to
584 thread_wrapper not holding the lock, and someone has recycled
585 this thread slot in the meantime, we're hosed. Is that
586 possible, though? */
587 VG_(release_BigLock_LL)("wqthread_hijack(2)");
588 call_on_new_stack_0_1(tst->os_state.valgrind_stack_init_SP, 0,
589 start_thread_NORETURN, (Word)tst);
590 }
591
592 /*NOTREACHED*/
593 vg_assert(0);
594 }
595
596 #endif // defined(VGP_amd64_darwin)
597
598 /*--------------------------------------------------------------------*/
599 /*--- end ---*/
600 /*--------------------------------------------------------------------*/
601