Commit | Line | Data |
---|---|---|
abaf6977 | 1 | /* |
2eb5f31b | 2 | * Copyright (C) 2015 Thomas Meyer (thomas@m3y3r.de) |
ba180fd4 | 3 | * Copyright (C) 2002- 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) |
abaf6977 GS |
4 | * Licensed under the GPL |
5 | */ | |
6 | ||
7 | #include <stdlib.h> | |
abaf6977 | 8 | #include <unistd.h> |
abaf6977 | 9 | #include <sched.h> |
ba180fd4 JD |
10 | #include <errno.h> |
11 | #include <string.h> | |
abaf6977 | 12 | #include <sys/mman.h> |
ba180fd4 JD |
13 | #include <sys/wait.h> |
14 | #include <asm/unistd.h> | |
37185b33 AV |
15 | #include <as-layout.h> |
16 | #include <init.h> | |
17 | #include <kern_util.h> | |
18 | #include <mem.h> | |
19 | #include <os.h> | |
37185b33 AV |
20 | #include <ptrace_user.h> |
21 | #include <registers.h> | |
22 | #include <skas.h> | |
37185b33 | 23 | #include <sysdep/stub.h> |
abaf6977 GS |
24 | |
25 | int is_skas_winch(int pid, int fd, void *data) | |
26 | { | |
17e05209 | 27 | return pid == getpgrp(); |
abaf6977 GS |
28 | } |
29 | ||
f30c2c98 JD |
30 | static int ptrace_dump_regs(int pid) |
31 | { | |
3e6f2ac4 JD |
32 | unsigned long regs[MAX_REG_NR]; |
33 | int i; | |
f30c2c98 | 34 | |
3e6f2ac4 JD |
35 | if (ptrace(PTRACE_GETREGS, pid, 0, regs) < 0) |
36 | return -errno; | |
ba180fd4 JD |
37 | |
38 | printk(UM_KERN_ERR "Stub registers -\n"); | |
39 | for (i = 0; i < ARRAY_SIZE(regs); i++) | |
40 | printk(UM_KERN_ERR "\t%d - %lx\n", i, regs[i]); | |
f30c2c98 | 41 | |
3e6f2ac4 | 42 | return 0; |
f30c2c98 JD |
43 | } |
44 | ||
16dd07bc JD |
45 | /* |
46 | * Signals that are OK to receive in the stub - we'll just continue it. | |
47 | * SIGWINCH will happen when UML is inside a detached screen. | |
48 | */ | |
2eb5f31b | 49 | #define STUB_SIG_MASK ((1 << SIGALRM) | (1 << SIGWINCH)) |
16dd07bc JD |
50 | |
51 | /* Signals that the stub will finish with - anything else is an error */ | |
ee3d9bd4 | 52 | #define STUB_DONE_MASK (1 << SIGTRAP) |
16dd07bc JD |
53 | |
54 | void wait_stub_done(int pid) | |
abaf6977 | 55 | { |
ae5db6d1 | 56 | int n, status, err; |
abaf6977 | 57 | |
ba180fd4 | 58 | while (1) { |
4dbed85a | 59 | CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED | __WALL)); |
ba180fd4 | 60 | if ((n < 0) || !WIFSTOPPED(status)) |
16dd07bc JD |
61 | goto bad_wait; |
62 | ||
ba180fd4 | 63 | if (((1 << WSTOPSIG(status)) & STUB_SIG_MASK) == 0) |
16dd07bc JD |
64 | break; |
65 | ||
66 | err = ptrace(PTRACE_CONT, pid, 0, 0); | |
3e6f2ac4 JD |
67 | if (err) { |
68 | printk(UM_KERN_ERR "wait_stub_done : continue failed, " | |
69 | "errno = %d\n", errno); | |
70 | fatal_sigsegv(); | |
71 | } | |
abaf6977 | 72 | } |
16dd07bc | 73 | |
ba180fd4 | 74 | if (((1 << WSTOPSIG(status)) & STUB_DONE_MASK) != 0) |
16dd07bc JD |
75 | return; |
76 | ||
77 | bad_wait: | |
78 | err = ptrace_dump_regs(pid); | |
ba180fd4 JD |
79 | if (err) |
80 | printk(UM_KERN_ERR "Failed to get registers from stub, " | |
81 | "errno = %d\n", -err); | |
3e6f2ac4 JD |
82 | printk(UM_KERN_ERR "wait_stub_done : failed to wait for SIGTRAP, " |
83 | "pid = %d, n = %d, errno = %d, status = 0x%x\n", pid, n, errno, | |
84 | status); | |
ae5db6d1 | 85 | fatal_sigsegv(); |
abaf6977 GS |
86 | } |
87 | ||
88 | extern unsigned long current_stub_stack(void); | |
89 | ||
99764fa4 | 90 | static void get_skas_faultinfo(int pid, struct faultinfo *fi) |
abaf6977 GS |
91 | { |
92 | int err; | |
d0b5e15f | 93 | unsigned long fpregs[FP_SIZE]; |
abaf6977 | 94 | |
d0b5e15f RW |
95 | err = get_fp_registers(pid, fpregs); |
96 | if (err < 0) { | |
97 | printk(UM_KERN_ERR "save_fp_registers returned %d\n", | |
98 | err); | |
99 | fatal_sigsegv(); | |
abaf6977 | 100 | } |
d0b5e15f RW |
101 | err = ptrace(PTRACE_CONT, pid, 0, SIGSEGV); |
102 | if (err) { | |
103 | printk(UM_KERN_ERR "Failed to continue stub, pid = %d, " | |
104 | "errno = %d\n", pid, errno); | |
105 | fatal_sigsegv(); | |
106 | } | |
107 | wait_stub_done(pid); | |
abaf6977 | 108 | |
d0b5e15f RW |
109 | /* |
110 | * faultinfo is prepared by the stub-segv-handler at start of | |
111 | * the stub stack page. We just have to copy it. | |
112 | */ | |
113 | memcpy(fi, (void *)current_stub_stack(), sizeof(*fi)); | |
2f56debd | 114 | |
d0b5e15f RW |
115 | err = put_fp_registers(pid, fpregs); |
116 | if (err < 0) { | |
117 | printk(UM_KERN_ERR "put_fp_registers returned %d\n", | |
118 | err); | |
119 | fatal_sigsegv(); | |
abaf6977 GS |
120 | } |
121 | } | |
122 | ||
77bf4400 | 123 | static void handle_segv(int pid, struct uml_pt_regs * regs) |
abaf6977 | 124 | { |
77bf4400 JD |
125 | get_skas_faultinfo(pid, ®s->faultinfo); |
126 | segv(regs->faultinfo, 0, 1, NULL); | |
abaf6977 GS |
127 | } |
128 | ||
ba180fd4 JD |
129 | /* |
130 | * To use the same value of using_sysemu as the caller, ask it that value | |
131 | * (in local_using_sysemu | |
132 | */ | |
133 | static void handle_trap(int pid, struct uml_pt_regs *regs, | |
134 | int local_using_sysemu) | |
abaf6977 GS |
135 | { |
136 | int err, status; | |
137 | ||
e06173bd JD |
138 | if ((UPT_IP(regs) >= STUB_START) && (UPT_IP(regs) < STUB_END)) |
139 | fatal_sigsegv(); | |
140 | ||
abaf6977 GS |
141 | if (!local_using_sysemu) |
142 | { | |
966e803a | 143 | err = ptrace(PTRACE_POKEUSER, pid, PT_SYSCALL_NR_OFFSET, |
abaf6977 | 144 | __NR_getpid); |
3e6f2ac4 JD |
145 | if (err < 0) { |
146 | printk(UM_KERN_ERR "handle_trap - nullifying syscall " | |
147 | "failed, errno = %d\n", errno); | |
148 | fatal_sigsegv(); | |
149 | } | |
abaf6977 GS |
150 | |
151 | err = ptrace(PTRACE_SYSCALL, pid, 0, 0); | |
3e6f2ac4 JD |
152 | if (err < 0) { |
153 | printk(UM_KERN_ERR "handle_trap - continuing to end of " | |
154 | "syscall failed, errno = %d\n", errno); | |
155 | fatal_sigsegv(); | |
156 | } | |
abaf6977 | 157 | |
4dbed85a | 158 | CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED | __WALL)); |
ba180fd4 | 159 | if ((err < 0) || !WIFSTOPPED(status) || |
3e6f2ac4 JD |
160 | (WSTOPSIG(status) != SIGTRAP + 0x80)) { |
161 | err = ptrace_dump_regs(pid); | |
162 | if (err) | |
163 | printk(UM_KERN_ERR "Failed to get registers " | |
ba180fd4 | 164 | "from process, errno = %d\n", -err); |
3e6f2ac4 JD |
165 | printk(UM_KERN_ERR "handle_trap - failed to wait at " |
166 | "end of syscall, errno = %d, status = %d\n", | |
167 | errno, status); | |
168 | fatal_sigsegv(); | |
169 | } | |
abaf6977 GS |
170 | } |
171 | ||
172 | handle_syscall(regs); | |
173 | } | |
174 | ||
5f32943b | 175 | extern char __syscall_stub_start[]; |
abaf6977 GS |
176 | |
177 | static int userspace_tramp(void *stack) | |
178 | { | |
179 | void *addr; | |
2eb5f31b | 180 | int fd; |
d0b5e15f | 181 | unsigned long long offset; |
abaf6977 GS |
182 | |
183 | ptrace(PTRACE_TRACEME, 0, 0, 0); | |
184 | ||
a24864a1 | 185 | signal(SIGTERM, SIG_DFL); |
ee3d9bd4 | 186 | signal(SIGWINCH, SIG_IGN); |
abaf6977 | 187 | |
d0b5e15f RW |
188 | /* |
189 | * This has a pte, but it can't be mapped in with the usual | |
190 | * tlb_flush mechanism because this is part of that mechanism | |
191 | */ | |
5f32943b | 192 | fd = phys_mapping(to_phys(__syscall_stub_start), &offset); |
d0b5e15f RW |
193 | addr = mmap64((void *) STUB_CODE, UM_KERN_PAGE_SIZE, |
194 | PROT_EXEC, MAP_FIXED | MAP_PRIVATE, fd, offset); | |
195 | if (addr == MAP_FAILED) { | |
196 | printk(UM_KERN_ERR "mapping mmap stub at 0x%lx failed, " | |
197 | "errno = %d\n", STUB_CODE, errno); | |
198 | exit(1); | |
199 | } | |
200 | ||
201 | if (stack != NULL) { | |
202 | fd = phys_mapping(to_phys(stack), &offset); | |
203 | addr = mmap((void *) STUB_DATA, | |
204 | UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE, | |
205 | MAP_FIXED | MAP_SHARED, fd, offset); | |
ba180fd4 | 206 | if (addr == MAP_FAILED) { |
d0b5e15f RW |
207 | printk(UM_KERN_ERR "mapping segfault stack " |
208 | "at 0x%lx failed, errno = %d\n", | |
209 | STUB_DATA, errno); | |
abaf6977 GS |
210 | exit(1); |
211 | } | |
abaf6977 | 212 | } |
d0b5e15f | 213 | if (stack != NULL) { |
4b84c69b JD |
214 | struct sigaction sa; |
215 | ||
54ae36f2 | 216 | unsigned long v = STUB_CODE + |
abaf6977 | 217 | (unsigned long) stub_segv_handler - |
5f32943b | 218 | (unsigned long) __syscall_stub_start; |
abaf6977 | 219 | |
54ae36f2 | 220 | set_sigstack((void *) STUB_DATA, UM_KERN_PAGE_SIZE); |
4b84c69b | 221 | sigemptyset(&sa.sa_mask); |
9b25fcbd AV |
222 | sa.sa_flags = SA_ONSTACK | SA_NODEFER | SA_SIGINFO; |
223 | sa.sa_sigaction = (void *) v; | |
4b84c69b | 224 | sa.sa_restorer = NULL; |
3e6f2ac4 JD |
225 | if (sigaction(SIGSEGV, &sa, NULL) < 0) { |
226 | printk(UM_KERN_ERR "userspace_tramp - setting SIGSEGV " | |
227 | "handler failed - errno = %d\n", errno); | |
228 | exit(1); | |
229 | } | |
abaf6977 GS |
230 | } |
231 | ||
512b6fb1 | 232 | kill(os_getpid(), SIGSTOP); |
ba180fd4 | 233 | return 0; |
abaf6977 GS |
234 | } |
235 | ||
236 | /* Each element set once, and only accessed by a single processor anyway */ | |
237 | #undef NR_CPUS | |
238 | #define NR_CPUS 1 | |
239 | int userspace_pid[NR_CPUS]; | |
240 | ||
241 | int start_userspace(unsigned long stub_stack) | |
242 | { | |
243 | void *stack; | |
244 | unsigned long sp; | |
3e6f2ac4 | 245 | int pid, status, n, flags, err; |
abaf6977 | 246 | |
c539ab73 JD |
247 | stack = mmap(NULL, UM_KERN_PAGE_SIZE, |
248 | PROT_READ | PROT_WRITE | PROT_EXEC, | |
abaf6977 | 249 | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); |
3e6f2ac4 JD |
250 | if (stack == MAP_FAILED) { |
251 | err = -errno; | |
252 | printk(UM_KERN_ERR "start_userspace : mmap failed, " | |
b5498832 | 253 | "errno = %d\n", errno); |
3e6f2ac4 JD |
254 | return err; |
255 | } | |
256 | ||
c539ab73 | 257 | sp = (unsigned long) stack + UM_KERN_PAGE_SIZE - sizeof(void *); |
abaf6977 | 258 | |
d0b5e15f | 259 | flags = CLONE_FILES | SIGCHLD; |
ba180fd4 | 260 | |
abaf6977 | 261 | pid = clone(userspace_tramp, (void *) sp, flags, (void *) stub_stack); |
3e6f2ac4 JD |
262 | if (pid < 0) { |
263 | err = -errno; | |
264 | printk(UM_KERN_ERR "start_userspace : clone failed, " | |
b5498832 | 265 | "errno = %d\n", errno); |
3e6f2ac4 JD |
266 | return err; |
267 | } | |
abaf6977 GS |
268 | |
269 | do { | |
4dbed85a | 270 | CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED | __WALL)); |
3e6f2ac4 JD |
271 | if (n < 0) { |
272 | err = -errno; | |
273 | printk(UM_KERN_ERR "start_userspace : wait failed, " | |
b5498832 | 274 | "errno = %d\n", errno); |
3e6f2ac4 JD |
275 | goto out_kill; |
276 | } | |
2eb5f31b | 277 | } while (WIFSTOPPED(status) && (WSTOPSIG(status) == SIGALRM)); |
abaf6977 | 278 | |
3e6f2ac4 JD |
279 | if (!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGSTOP)) { |
280 | err = -EINVAL; | |
281 | printk(UM_KERN_ERR "start_userspace : expected SIGSTOP, got " | |
b5498832 | 282 | "status = %d\n", status); |
3e6f2ac4 JD |
283 | goto out_kill; |
284 | } | |
abaf6977 | 285 | |
ba180fd4 | 286 | if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL, |
3e6f2ac4 JD |
287 | (void *) PTRACE_O_TRACESYSGOOD) < 0) { |
288 | err = -errno; | |
289 | printk(UM_KERN_ERR "start_userspace : PTRACE_OLDSETOPTIONS " | |
290 | "failed, errno = %d\n", errno); | |
291 | goto out_kill; | |
292 | } | |
abaf6977 | 293 | |
3e6f2ac4 JD |
294 | if (munmap(stack, UM_KERN_PAGE_SIZE) < 0) { |
295 | err = -errno; | |
296 | printk(UM_KERN_ERR "start_userspace : munmap failed, " | |
297 | "errno = %d\n", errno); | |
298 | goto out_kill; | |
299 | } | |
abaf6977 | 300 | |
ba180fd4 | 301 | return pid; |
3e6f2ac4 JD |
302 | |
303 | out_kill: | |
304 | os_kill_ptraced_process(pid, 1); | |
305 | return err; | |
abaf6977 GS |
306 | } |
307 | ||
77bf4400 | 308 | void userspace(struct uml_pt_regs *regs) |
abaf6977 GS |
309 | { |
310 | int err, status, op, pid = userspace_pid[0]; | |
2ea5bc5e JD |
311 | /* To prevent races if using_sysemu changes under us.*/ |
312 | int local_using_sysemu; | |
d3c1cfcd | 313 | siginfo_t si; |
abaf6977 | 314 | |
b8a42095 AV |
315 | /* Handle any immediate reschedules or signals */ |
316 | interrupt_end(); | |
317 | ||
ba180fd4 | 318 | while (1) { |
2eb5f31b | 319 | |
3e6f2ac4 JD |
320 | /* |
321 | * This can legitimately fail if the process loads a | |
322 | * bogus value into a segment register. It will | |
323 | * segfault and PTRACE_GETREGS will read that value | |
324 | * out of the process. However, PTRACE_SETREGS will | |
325 | * fail. In this case, there is nothing to do but | |
326 | * just kill the process. | |
327 | */ | |
d25f2e12 | 328 | if (ptrace(PTRACE_SETREGS, pid, 0, regs->gp)) |
3e6f2ac4 | 329 | fatal_sigsegv(); |
abaf6977 | 330 | |
fbfe9c84 IL |
331 | if (put_fp_registers(pid, regs->fp)) |
332 | fatal_sigsegv(); | |
333 | ||
abaf6977 GS |
334 | /* Now we set local_using_sysemu to be used for one loop */ |
335 | local_using_sysemu = get_using_sysemu(); | |
336 | ||
2ea5bc5e JD |
337 | op = SELECT_PTRACE_OPERATION(local_using_sysemu, |
338 | singlestepping(NULL)); | |
abaf6977 | 339 | |
3e6f2ac4 JD |
340 | if (ptrace(op, pid, 0, 0)) { |
341 | printk(UM_KERN_ERR "userspace - ptrace continue " | |
342 | "failed, op = %d, errno = %d\n", op, errno); | |
343 | fatal_sigsegv(); | |
344 | } | |
abaf6977 | 345 | |
4dbed85a | 346 | CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED | __WALL)); |
3e6f2ac4 JD |
347 | if (err < 0) { |
348 | printk(UM_KERN_ERR "userspace - wait failed, " | |
349 | "errno = %d\n", errno); | |
350 | fatal_sigsegv(); | |
351 | } | |
abaf6977 | 352 | |
77bf4400 | 353 | regs->is_user = 1; |
3e6f2ac4 JD |
354 | if (ptrace(PTRACE_GETREGS, pid, 0, regs->gp)) { |
355 | printk(UM_KERN_ERR "userspace - PTRACE_GETREGS failed, " | |
356 | "errno = %d\n", errno); | |
357 | fatal_sigsegv(); | |
358 | } | |
d25f2e12 | 359 | |
fbfe9c84 IL |
360 | if (get_fp_registers(pid, regs->fp)) { |
361 | printk(UM_KERN_ERR "userspace - get_fp_registers failed, " | |
362 | "errno = %d\n", errno); | |
363 | fatal_sigsegv(); | |
364 | } | |
365 | ||
abaf6977 GS |
366 | UPT_SYSCALL_NR(regs) = -1; /* Assume: It's not a syscall */ |
367 | ||
ba180fd4 | 368 | if (WIFSTOPPED(status)) { |
16dd07bc | 369 | int sig = WSTOPSIG(status); |
d3c1cfcd | 370 | |
9a8c1359 | 371 | ptrace(PTRACE_GETSIGINFO, pid, 0, (struct siginfo *)&si); |
d3c1cfcd | 372 | |
5134d8fe | 373 | switch (sig) { |
abaf6977 | 374 | case SIGSEGV: |
d0b5e15f | 375 | if (PTRACE_FULL_FAULTINFO) { |
ba180fd4 JD |
376 | get_skas_faultinfo(pid, |
377 | ®s->faultinfo); | |
9a8c1359 | 378 | (*sig_info[SIGSEGV])(SIGSEGV, (struct siginfo *)&si, |
d3c1cfcd | 379 | regs); |
16dd07bc | 380 | } |
abaf6977 GS |
381 | else handle_segv(pid, regs); |
382 | break; | |
383 | case SIGTRAP + 0x80: | |
384 | handle_trap(pid, regs, local_using_sysemu); | |
385 | break; | |
386 | case SIGTRAP: | |
9a8c1359 | 387 | relay_signal(SIGTRAP, (struct siginfo *)&si, regs); |
abaf6977 | 388 | break; |
2eb5f31b | 389 | case SIGALRM: |
d2753a6d JD |
390 | break; |
391 | case SIGIO: | |
abaf6977 GS |
392 | case SIGILL: |
393 | case SIGBUS: | |
394 | case SIGFPE: | |
395 | case SIGWINCH: | |
16dd07bc | 396 | block_signals(); |
9a8c1359 | 397 | (*sig_info[sig])(sig, (struct siginfo *)&si, regs); |
16dd07bc | 398 | unblock_signals(); |
abaf6977 GS |
399 | break; |
400 | default: | |
96cee304 | 401 | printk(UM_KERN_ERR "userspace - child stopped " |
ba180fd4 | 402 | "with signal %d\n", sig); |
3e6f2ac4 | 403 | fatal_sigsegv(); |
abaf6977 | 404 | } |
abaf6977 GS |
405 | pid = userspace_pid[0]; |
406 | interrupt_end(); | |
407 | ||
408 | /* Avoid -ERESTARTSYS handling in host */ | |
ba180fd4 | 409 | if (PT_SYSCALL_NR_OFFSET != PT_SYSCALL_RET_OFFSET) |
18baddda | 410 | PT_SYSCALL_NR(regs->gp) = -1; |
abaf6977 GS |
411 | } |
412 | } | |
413 | } | |
abaf6977 | 414 | |
16dd07bc | 415 | static unsigned long thread_regs[MAX_REG_NR]; |
fbfe9c84 | 416 | static unsigned long thread_fp_regs[FP_SIZE]; |
16dd07bc JD |
417 | |
418 | static int __init init_thread_regs(void) | |
419 | { | |
fbfe9c84 | 420 | get_safe_registers(thread_regs, thread_fp_regs); |
16dd07bc | 421 | /* Set parent's instruction pointer to start of clone-stub */ |
54ae36f2 | 422 | thread_regs[REGS_IP_INDEX] = STUB_CODE + |
16dd07bc | 423 | (unsigned long) stub_clone_handler - |
5f32943b | 424 | (unsigned long) __syscall_stub_start; |
54ae36f2 | 425 | thread_regs[REGS_SP_INDEX] = STUB_DATA + UM_KERN_PAGE_SIZE - |
16dd07bc JD |
426 | sizeof(void *); |
427 | #ifdef __SIGNAL_FRAMESIZE | |
428 | thread_regs[REGS_SP_INDEX] -= __SIGNAL_FRAMESIZE; | |
429 | #endif | |
430 | return 0; | |
431 | } | |
432 | ||
433 | __initcall(init_thread_regs); | |
434 | ||
abaf6977 GS |
435 | int copy_context_skas0(unsigned long new_stack, int pid) |
436 | { | |
437 | int err; | |
abaf6977 GS |
438 | unsigned long current_stack = current_stub_stack(); |
439 | struct stub_data *data = (struct stub_data *) current_stack; | |
440 | struct stub_data *child_data = (struct stub_data *) new_stack; | |
0a7675aa | 441 | unsigned long long new_offset; |
abaf6977 GS |
442 | int new_fd = phys_mapping(to_phys((void *)new_stack), &new_offset); |
443 | ||
ba180fd4 JD |
444 | /* |
445 | * prepare offset and fd of child's stack as argument for parent's | |
abaf6977 GS |
446 | * and child's mmap2 calls |
447 | */ | |
2eb5f31b AI |
448 | *data = ((struct stub_data) { |
449 | .offset = MMAP_OFFSET(new_offset), | |
450 | .fd = new_fd | |
451 | }); | |
d2753a6d | 452 | |
16dd07bc | 453 | err = ptrace_setregs(pid, thread_regs); |
3e6f2ac4 JD |
454 | if (err < 0) { |
455 | err = -errno; | |
456 | printk(UM_KERN_ERR "copy_context_skas0 : PTRACE_SETREGS " | |
457 | "failed, pid = %d, errno = %d\n", pid, -err); | |
458 | return err; | |
459 | } | |
abaf6977 | 460 | |
fbfe9c84 IL |
461 | err = put_fp_registers(pid, thread_fp_regs); |
462 | if (err < 0) { | |
463 | printk(UM_KERN_ERR "copy_context_skas0 : put_fp_registers " | |
464 | "failed, pid = %d, err = %d\n", pid, err); | |
465 | return err; | |
466 | } | |
467 | ||
abaf6977 GS |
468 | /* set a well known return code for detection of child write failure */ |
469 | child_data->err = 12345678; | |
470 | ||
ba180fd4 JD |
471 | /* |
472 | * Wait, until parent has finished its work: read child's pid from | |
abaf6977 GS |
473 | * parent's stack, and check, if bad result. |
474 | */ | |
16dd07bc | 475 | err = ptrace(PTRACE_CONT, pid, 0, 0); |
3e6f2ac4 JD |
476 | if (err) { |
477 | err = -errno; | |
478 | printk(UM_KERN_ERR "Failed to continue new process, pid = %d, " | |
479 | "errno = %d\n", pid, errno); | |
480 | return err; | |
481 | } | |
482 | ||
16dd07bc | 483 | wait_stub_done(pid); |
abaf6977 GS |
484 | |
485 | pid = data->err; | |
3e6f2ac4 JD |
486 | if (pid < 0) { |
487 | printk(UM_KERN_ERR "copy_context_skas0 - stub-parent reports " | |
488 | "error %d\n", -pid); | |
489 | return pid; | |
490 | } | |
abaf6977 | 491 | |
ba180fd4 JD |
492 | /* |
493 | * Wait, until child has finished too: read child's result from | |
abaf6977 GS |
494 | * child's stack and check it. |
495 | */ | |
16dd07bc | 496 | wait_stub_done(pid); |
3e6f2ac4 JD |
497 | if (child_data->err != STUB_DATA) { |
498 | printk(UM_KERN_ERR "copy_context_skas0 - stub-child reports " | |
499 | "error %ld\n", child_data->err); | |
500 | err = child_data->err; | |
501 | goto out_kill; | |
502 | } | |
abaf6977 GS |
503 | |
504 | if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL, | |
3e6f2ac4 JD |
505 | (void *)PTRACE_O_TRACESYSGOOD) < 0) { |
506 | err = -errno; | |
507 | printk(UM_KERN_ERR "copy_context_skas0 : PTRACE_OLDSETOPTIONS " | |
508 | "failed, errno = %d\n", errno); | |
509 | goto out_kill; | |
510 | } | |
abaf6977 GS |
511 | |
512 | return pid; | |
3e6f2ac4 JD |
513 | |
514 | out_kill: | |
515 | os_kill_ptraced_process(pid, 1); | |
516 | return err; | |
abaf6977 GS |
517 | } |
518 | ||
3c917350 | 519 | void new_thread(void *stack, jmp_buf *buf, void (*handler)(void)) |
abaf6977 | 520 | { |
3c917350 | 521 | (*buf)[0].JB_IP = (unsigned long) handler; |
e1a79c40 JD |
522 | (*buf)[0].JB_SP = (unsigned long) stack + UM_THREAD_SIZE - |
523 | sizeof(void *); | |
abaf6977 GS |
524 | } |
525 | ||
e2216feb | 526 | #define INIT_JMP_NEW_THREAD 0 |
3c917350 JD |
527 | #define INIT_JMP_CALLBACK 1 |
528 | #define INIT_JMP_HALT 2 | |
529 | #define INIT_JMP_REBOOT 3 | |
abaf6977 | 530 | |
3c917350 | 531 | void switch_threads(jmp_buf *me, jmp_buf *you) |
abaf6977 | 532 | { |
ba180fd4 | 533 | if (UML_SETJMP(me) == 0) |
3c917350 | 534 | UML_LONGJMP(you, 1); |
abaf6977 GS |
535 | } |
536 | ||
ad28e029 | 537 | static jmp_buf initial_jmpbuf; |
abaf6977 GS |
538 | |
539 | /* XXX Make these percpu */ | |
540 | static void (*cb_proc)(void *arg); | |
541 | static void *cb_arg; | |
ad28e029 | 542 | static jmp_buf *cb_back; |
abaf6977 | 543 | |
3c917350 | 544 | int start_idle_thread(void *stack, jmp_buf *switch_buf) |
abaf6977 | 545 | { |
a5df0d1a | 546 | int n; |
abaf6977 | 547 | |
00361683 | 548 | set_handler(SIGWINCH); |
abaf6977 | 549 | |
77f6af77 JD |
550 | /* |
551 | * Can't use UML_SETJMP or UML_LONGJMP here because they save | |
552 | * and restore signals, with the possible side-effect of | |
553 | * trying to handle any signals which came when they were | |
554 | * blocked, which can't be done on this stack. | |
555 | * Signals must be blocked when jumping back here and restored | |
556 | * after returning to the jumper. | |
557 | */ | |
558 | n = setjmp(initial_jmpbuf); | |
5134d8fe | 559 | switch (n) { |
abaf6977 | 560 | case INIT_JMP_NEW_THREAD: |
33bbc306 | 561 | (*switch_buf)[0].JB_IP = (unsigned long) uml_finishsetup; |
3c917350 | 562 | (*switch_buf)[0].JB_SP = (unsigned long) stack + |
e1a79c40 | 563 | UM_THREAD_SIZE - sizeof(void *); |
abaf6977 GS |
564 | break; |
565 | case INIT_JMP_CALLBACK: | |
566 | (*cb_proc)(cb_arg); | |
77f6af77 | 567 | longjmp(*cb_back, 1); |
abaf6977 GS |
568 | break; |
569 | case INIT_JMP_HALT: | |
570 | kmalloc_ok = 0; | |
ba180fd4 | 571 | return 0; |
abaf6977 GS |
572 | case INIT_JMP_REBOOT: |
573 | kmalloc_ok = 0; | |
ba180fd4 | 574 | return 1; |
abaf6977 | 575 | default: |
3e6f2ac4 JD |
576 | printk(UM_KERN_ERR "Bad sigsetjmp return in " |
577 | "start_idle_thread - %d\n", n); | |
578 | fatal_sigsegv(); | |
abaf6977 | 579 | } |
77f6af77 | 580 | longjmp(*switch_buf, 1); |
abaf6977 GS |
581 | } |
582 | ||
583 | void initial_thread_cb_skas(void (*proc)(void *), void *arg) | |
584 | { | |
ad28e029 | 585 | jmp_buf here; |
abaf6977 GS |
586 | |
587 | cb_proc = proc; | |
588 | cb_arg = arg; | |
589 | cb_back = &here; | |
590 | ||
591 | block_signals(); | |
ba180fd4 | 592 | if (UML_SETJMP(&here) == 0) |
ad28e029 | 593 | UML_LONGJMP(&initial_jmpbuf, INIT_JMP_CALLBACK); |
abaf6977 GS |
594 | unblock_signals(); |
595 | ||
596 | cb_proc = NULL; | |
597 | cb_arg = NULL; | |
598 | cb_back = NULL; | |
599 | } | |
600 | ||
601 | void halt_skas(void) | |
602 | { | |
603 | block_signals(); | |
ad28e029 | 604 | UML_LONGJMP(&initial_jmpbuf, INIT_JMP_HALT); |
abaf6977 GS |
605 | } |
606 | ||
607 | void reboot_skas(void) | |
608 | { | |
609 | block_signals(); | |
ad28e029 | 610 | UML_LONGJMP(&initial_jmpbuf, INIT_JMP_REBOOT); |
abaf6977 GS |
611 | } |
612 | ||
77bf4400 | 613 | void __switch_mm(struct mm_id *mm_idp) |
abaf6977 | 614 | { |
d0b5e15f | 615 | userspace_pid[0] = mm_idp->u.pid; |
abaf6977 | 616 | } |