1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/arch/parisc/kernel/signal.c: Architecture-specific signal
4 * handling support.
5 *
6 * Copyright (C) 2000 David Huggins-Daines <dhd@debian.org>
7 * Copyright (C) 2000 Linuxcare, Inc.
8 *
9 * Based on the ia64, i386, and alpha versions.
10 *
11 * Like the IA-64, we are a recent enough port (we are *starting*
12 * with glibc2.2) that we do not need to support the old non-realtime
13 * Linux signals. Therefore we don't.
14 */
15
16 #include <linux/sched.h>
17 #include <linux/sched/debug.h>
18 #include <linux/mm.h>
19 #include <linux/smp.h>
20 #include <linux/kernel.h>
21 #include <linux/signal.h>
22 #include <linux/errno.h>
23 #include <linux/wait.h>
24 #include <linux/ptrace.h>
25 #include <linux/tracehook.h>
26 #include <linux/unistd.h>
27 #include <linux/stddef.h>
28 #include <linux/compat.h>
29 #include <linux/elf.h>
30 #include <asm/ucontext.h>
31 #include <asm/rt_sigframe.h>
32 #include <linux/uaccess.h>
33 #include <asm/pgalloc.h>
34 #include <asm/cacheflush.h>
35 #include <asm/asm-offsets.h>
36
37 #ifdef CONFIG_COMPAT
38 #include "signal32.h"
39 #endif
40
41 #define DEBUG_SIG 0
42 #define DEBUG_SIG_LEVEL 2
43
44 #if DEBUG_SIG
45 #define DBG(LEVEL, ...) \
46 ((DEBUG_SIG_LEVEL >= LEVEL) \
47 ? printk(__VA_ARGS__) : (void) 0)
48 #else
49 #define DBG(LEVEL, ...)
50 #endif
51
52 /* gcc will complain if a pointer is cast to an integer of different
53 * size. If you really need to do this (and we do for an ELF32 user
54 * application in an ELF64 kernel) then you have to do a cast to an
55 * integer of the same size first. The A() macro accomplishes
56 * this. */
57 #define A(__x) ((unsigned long)(__x))
58
59 /*
60 * Do a signal return - restore sigcontext.
61 */
62
63 /* Trampoline for calling rt_sigreturn() */
64 #define INSN_LDI_R25_0 0x34190000 /* ldi 0,%r25 (in_syscall=0) */
65 #define INSN_LDI_R25_1 0x34190002 /* ldi 1,%r25 (in_syscall=1) */
66 #define INSN_LDI_R20 0x3414015a /* ldi __NR_rt_sigreturn,%r20 */
67 #define INSN_BLE_SR2_R0 0xe4008200 /* be,l 0x100(%sr2,%r0),%sr0,%r31 */
68 #define INSN_NOP 0x08000240 /* nop */
69 /* For debugging */
70 #define INSN_DIE_HORRIBLY 0x68000ccc /* stw %r0,0x666(%sr0,%r0) */
71
72 static long
restore_sigcontext(struct sigcontext __user * sc,struct pt_regs * regs)73 restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs)
74 {
75 long err = 0;
76
77 err |= __copy_from_user(regs->gr, sc->sc_gr, sizeof(regs->gr));
78 err |= __copy_from_user(regs->fr, sc->sc_fr, sizeof(regs->fr));
79 err |= __copy_from_user(regs->iaoq, sc->sc_iaoq, sizeof(regs->iaoq));
80 err |= __copy_from_user(regs->iasq, sc->sc_iasq, sizeof(regs->iasq));
81 err |= __get_user(regs->sar, &sc->sc_sar);
82 DBG(2,"restore_sigcontext: iaoq is %#lx / %#lx\n",
83 regs->iaoq[0],regs->iaoq[1]);
84 DBG(2,"restore_sigcontext: r28 is %ld\n", regs->gr[28]);
85 return err;
86 }
87
88 void
sys_rt_sigreturn(struct pt_regs * regs,int in_syscall)89 sys_rt_sigreturn(struct pt_regs *regs, int in_syscall)
90 {
91 struct rt_sigframe __user *frame;
92 sigset_t set;
93 unsigned long usp = (regs->gr[30] & ~(0x01UL));
94 unsigned long sigframe_size = PARISC_RT_SIGFRAME_SIZE;
95 #ifdef CONFIG_64BIT
96 struct compat_rt_sigframe __user * compat_frame;
97
98 if (is_compat_task())
99 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
100 #endif
101
102 current->restart_block.fn = do_no_restart_syscall;
103
104 /* Unwind the user stack to get the rt_sigframe structure. */
105 frame = (struct rt_sigframe __user *)
106 (usp - sigframe_size);
107 DBG(2,"sys_rt_sigreturn: frame is %p\n", frame);
108
109 regs->orig_r28 = 1; /* no restarts for sigreturn */
110
111 #ifdef CONFIG_64BIT
112 compat_frame = (struct compat_rt_sigframe __user *)frame;
113
114 if (is_compat_task()) {
115 DBG(2,"sys_rt_sigreturn: ELF32 process.\n");
116 if (get_compat_sigset(&set, &compat_frame->uc.uc_sigmask))
117 goto give_sigsegv;
118 } else
119 #endif
120 {
121 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
122 goto give_sigsegv;
123 }
124
125 set_current_blocked(&set);
126
127 /* Good thing we saved the old gr[30], eh? */
128 #ifdef CONFIG_64BIT
129 if (is_compat_task()) {
130 DBG(1,"sys_rt_sigreturn: compat_frame->uc.uc_mcontext 0x%p\n",
131 &compat_frame->uc.uc_mcontext);
132 // FIXME: Load upper half from register file
133 if (restore_sigcontext32(&compat_frame->uc.uc_mcontext,
134 &compat_frame->regs, regs))
135 goto give_sigsegv;
136 DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
137 usp, &compat_frame->uc.uc_stack);
138 if (compat_restore_altstack(&compat_frame->uc.uc_stack))
139 goto give_sigsegv;
140 } else
141 #endif
142 {
143 DBG(1,"sys_rt_sigreturn: frame->uc.uc_mcontext 0x%p\n",
144 &frame->uc.uc_mcontext);
145 if (restore_sigcontext(&frame->uc.uc_mcontext, regs))
146 goto give_sigsegv;
147 DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
148 usp, &frame->uc.uc_stack);
149 if (restore_altstack(&frame->uc.uc_stack))
150 goto give_sigsegv;
151 }
152
153
154
155 /* If we are on the syscall path IAOQ will not be restored, and
156 * if we are on the interrupt path we must not corrupt gr31.
157 */
158 if (in_syscall)
159 regs->gr[31] = regs->iaoq[0];
160 #if DEBUG_SIG
161 DBG(1,"sys_rt_sigreturn: returning to %#lx, DUMPING REGS:\n", regs->iaoq[0]);
162 show_regs(regs);
163 #endif
164 return;
165
166 give_sigsegv:
167 DBG(1,"sys_rt_sigreturn: Sending SIGSEGV\n");
168 force_sig(SIGSEGV, current);
169 return;
170 }
171
172 /*
173 * Set up a signal frame.
174 */
175
176 static inline void __user *
get_sigframe(struct k_sigaction * ka,unsigned long sp,size_t frame_size)177 get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
178 {
179 /*FIXME: ELF32 vs. ELF64 has different frame_size, but since we
180 don't use the parameter it doesn't matter */
181
182 DBG(1,"get_sigframe: ka = %#lx, sp = %#lx, frame_size = %#lx\n",
183 (unsigned long)ka, sp, frame_size);
184
185 /* Align alternate stack and reserve 64 bytes for the signal
186 handler's frame marker. */
187 if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp))
188 sp = (current->sas_ss_sp + 0x7f) & ~0x3f; /* Stacks grow up! */
189
190 DBG(1,"get_sigframe: Returning sp = %#lx\n", (unsigned long)sp);
191 return (void __user *) sp; /* Stacks grow up. Fun. */
192 }
193
194 static long
setup_sigcontext(struct sigcontext __user * sc,struct pt_regs * regs,int in_syscall)195 setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, int in_syscall)
196
197 {
198 unsigned long flags = 0;
199 long err = 0;
200
201 if (on_sig_stack((unsigned long) sc))
202 flags |= PARISC_SC_FLAG_ONSTACK;
203 if (in_syscall) {
204 flags |= PARISC_SC_FLAG_IN_SYSCALL;
205 /* regs->iaoq is undefined in the syscall return path */
206 err |= __put_user(regs->gr[31], &sc->sc_iaoq[0]);
207 err |= __put_user(regs->gr[31]+4, &sc->sc_iaoq[1]);
208 err |= __put_user(regs->sr[3], &sc->sc_iasq[0]);
209 err |= __put_user(regs->sr[3], &sc->sc_iasq[1]);
210 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (in syscall)\n",
211 regs->gr[31], regs->gr[31]+4);
212 } else {
213 err |= __copy_to_user(sc->sc_iaoq, regs->iaoq, sizeof(regs->iaoq));
214 err |= __copy_to_user(sc->sc_iasq, regs->iasq, sizeof(regs->iasq));
215 DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (not in syscall)\n",
216 regs->iaoq[0], regs->iaoq[1]);
217 }
218
219 err |= __put_user(flags, &sc->sc_flags);
220 err |= __copy_to_user(sc->sc_gr, regs->gr, sizeof(regs->gr));
221 err |= __copy_to_user(sc->sc_fr, regs->fr, sizeof(regs->fr));
222 err |= __put_user(regs->sar, &sc->sc_sar);
223 DBG(1,"setup_sigcontext: r28 is %ld\n", regs->gr[28]);
224
225 return err;
226 }
227
228 static long
setup_rt_frame(struct ksignal * ksig,sigset_t * set,struct pt_regs * regs,int in_syscall)229 setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs,
230 int in_syscall)
231 {
232 struct rt_sigframe __user *frame;
233 unsigned long rp, usp;
234 unsigned long haddr, sigframe_size;
235 unsigned long start, end;
236 int err = 0;
237 #ifdef CONFIG_64BIT
238 struct compat_rt_sigframe __user * compat_frame;
239 #endif
240
241 usp = (regs->gr[30] & ~(0x01UL));
242 /*FIXME: frame_size parameter is unused, remove it. */
243 frame = get_sigframe(&ksig->ka, usp, sizeof(*frame));
244
245 DBG(1,"SETUP_RT_FRAME: START\n");
246 DBG(1,"setup_rt_frame: frame %p info %p\n", frame, ksig->info);
247
248
249 #ifdef CONFIG_64BIT
250
251 compat_frame = (struct compat_rt_sigframe __user *)frame;
252
253 if (is_compat_task()) {
254 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &compat_frame->info);
255 err |= copy_siginfo_to_user32(&compat_frame->info, &ksig->info);
256 err |= __compat_save_altstack( &compat_frame->uc.uc_stack, regs->gr[30]);
257 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &compat_frame->uc);
258 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &compat_frame->uc.uc_mcontext);
259 err |= setup_sigcontext32(&compat_frame->uc.uc_mcontext,
260 &compat_frame->regs, regs, in_syscall);
261 err |= put_compat_sigset(&compat_frame->uc.uc_sigmask, set,
262 sizeof(compat_sigset_t));
263 } else
264 #endif
265 {
266 DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &frame->info);
267 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
268 err |= __save_altstack(&frame->uc.uc_stack, regs->gr[30]);
269 DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &frame->uc);
270 DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &frame->uc.uc_mcontext);
271 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, in_syscall);
272 /* FIXME: Should probably be converted as well for the compat case */
273 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
274 }
275
276 if (err)
277 return -EFAULT;
278
279 /* Set up to return from userspace. If provided, use a stub
280 already in userspace. The first words of tramp are used to
281 save the previous sigrestartblock trampoline that might be
282 on the stack. We start the sigreturn trampoline at
283 SIGRESTARTBLOCK_TRAMP+X. */
284 err |= __put_user(in_syscall ? INSN_LDI_R25_1 : INSN_LDI_R25_0,
285 &frame->tramp[SIGRESTARTBLOCK_TRAMP+0]);
286 err |= __put_user(INSN_LDI_R20,
287 &frame->tramp[SIGRESTARTBLOCK_TRAMP+1]);
288 err |= __put_user(INSN_BLE_SR2_R0,
289 &frame->tramp[SIGRESTARTBLOCK_TRAMP+2]);
290 err |= __put_user(INSN_NOP, &frame->tramp[SIGRESTARTBLOCK_TRAMP+3]);
291
292 #if DEBUG_SIG
293 /* Assert that we're flushing in the correct space... */
294 {
295 unsigned long sid;
296 asm ("mfsp %%sr3,%0" : "=r" (sid));
297 DBG(1,"setup_rt_frame: Flushing 64 bytes at space %#x offset %p\n",
298 sid, frame->tramp);
299 }
300 #endif
301
302 start = (unsigned long) &frame->tramp[0];
303 end = (unsigned long) &frame->tramp[TRAMP_SIZE];
304 flush_user_dcache_range_asm(start, end);
305 flush_user_icache_range_asm(start, end);
306
307 /* TRAMP Words 0-4, Length 5 = SIGRESTARTBLOCK_TRAMP
308 * TRAMP Words 5-9, Length 4 = SIGRETURN_TRAMP
309 * So the SIGRETURN_TRAMP is at the end of SIGRESTARTBLOCK_TRAMP
310 */
311 rp = (unsigned long) &frame->tramp[SIGRESTARTBLOCK_TRAMP];
312
313 if (err)
314 return -EFAULT;
315
316 haddr = A(ksig->ka.sa.sa_handler);
317 /* The sa_handler may be a pointer to a function descriptor */
318 #ifdef CONFIG_64BIT
319 if (is_compat_task()) {
320 #endif
321 if (haddr & PA_PLABEL_FDESC) {
322 Elf32_Fdesc fdesc;
323 Elf32_Fdesc __user *ufdesc = (Elf32_Fdesc __user *)A(haddr & ~3);
324
325 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
326
327 if (err)
328 return -EFAULT;
329
330 haddr = fdesc.addr;
331 regs->gr[19] = fdesc.gp;
332 }
333 #ifdef CONFIG_64BIT
334 } else {
335 Elf64_Fdesc fdesc;
336 Elf64_Fdesc __user *ufdesc = (Elf64_Fdesc __user *)A(haddr & ~3);
337
338 err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
339
340 if (err)
341 return -EFAULT;
342
343 haddr = fdesc.addr;
344 regs->gr[19] = fdesc.gp;
345 DBG(1,"setup_rt_frame: 64 bit signal, exe=%#lx, r19=%#lx, in_syscall=%d\n",
346 haddr, regs->gr[19], in_syscall);
347 }
348 #endif
349
350 /* The syscall return path will create IAOQ values from r31.
351 */
352 sigframe_size = PARISC_RT_SIGFRAME_SIZE;
353 #ifdef CONFIG_64BIT
354 if (is_compat_task())
355 sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
356 #endif
357 if (in_syscall) {
358 regs->gr[31] = haddr;
359 #ifdef CONFIG_64BIT
360 if (!test_thread_flag(TIF_32BIT))
361 sigframe_size |= 1;
362 #endif
363 } else {
364 unsigned long psw = USER_PSW;
365 #ifdef CONFIG_64BIT
366 if (!test_thread_flag(TIF_32BIT))
367 psw |= PSW_W;
368 #endif
369
370 /* If we are singlestepping, arrange a trap to be delivered
371 when we return to userspace. Note the semantics -- we
372 should trap before the first insn in the handler is
373 executed. Ref:
374 http://sources.redhat.com/ml/gdb/2004-11/msg00245.html
375 */
376 if (pa_psw(current)->r) {
377 pa_psw(current)->r = 0;
378 psw |= PSW_R;
379 mtctl(-1, 0);
380 }
381
382 regs->gr[0] = psw;
383 regs->iaoq[0] = haddr | 3;
384 regs->iaoq[1] = regs->iaoq[0] + 4;
385 }
386
387 regs->gr[2] = rp; /* userland return pointer */
388 regs->gr[26] = ksig->sig; /* signal number */
389
390 #ifdef CONFIG_64BIT
391 if (is_compat_task()) {
392 regs->gr[25] = A(&compat_frame->info); /* siginfo pointer */
393 regs->gr[24] = A(&compat_frame->uc); /* ucontext pointer */
394 } else
395 #endif
396 {
397 regs->gr[25] = A(&frame->info); /* siginfo pointer */
398 regs->gr[24] = A(&frame->uc); /* ucontext pointer */
399 }
400
401 DBG(1,"setup_rt_frame: making sigreturn frame: %#lx + %#lx = %#lx\n",
402 regs->gr[30], sigframe_size,
403 regs->gr[30] + sigframe_size);
404 /* Raise the user stack pointer to make a proper call frame. */
405 regs->gr[30] = (A(frame) + sigframe_size);
406
407
408 DBG(1,"setup_rt_frame: sig deliver (%s,%d) frame=0x%p sp=%#lx iaoq=%#lx/%#lx rp=%#lx\n",
409 current->comm, current->pid, frame, regs->gr[30],
410 regs->iaoq[0], regs->iaoq[1], rp);
411
412 return 0;
413 }
414
415 /*
416 * OK, we're invoking a handler.
417 */
418
419 static void
handle_signal(struct ksignal * ksig,struct pt_regs * regs,int in_syscall)420 handle_signal(struct ksignal *ksig, struct pt_regs *regs, int in_syscall)
421 {
422 int ret;
423 sigset_t *oldset = sigmask_to_save();
424
425 DBG(1,"handle_signal: sig=%ld, ka=%p, info=%p, oldset=%p, regs=%p\n",
426 ksig->sig, ksig->ka, ksig->info, oldset, regs);
427
428 /* Set up the stack frame */
429 ret = setup_rt_frame(ksig, oldset, regs, in_syscall);
430
431 signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP) ||
432 test_thread_flag(TIF_BLOCKSTEP));
433
434 DBG(1,KERN_DEBUG "do_signal: Exit (success), regs->gr[28] = %ld\n",
435 regs->gr[28]);
436 }
437
438 /*
439 * Check how the syscall number gets loaded into %r20 within
440 * the delay branch in userspace and adjust as needed.
441 */
442
check_syscallno_in_delay_branch(struct pt_regs * regs)443 static void check_syscallno_in_delay_branch(struct pt_regs *regs)
444 {
445 u32 opcode, source_reg;
446 u32 __user *uaddr;
447 int err;
448
449 /* Usually we don't have to restore %r20 (the system call number)
450 * because it gets loaded in the delay slot of the branch external
451 * instruction via the ldi instruction.
452 * In some cases a register-to-register copy instruction might have
453 * been used instead, in which case we need to copy the syscall
454 * number into the source register before returning to userspace.
455 */
456
457 /* A syscall is just a branch, so all we have to do is fiddle the
458 * return pointer so that the ble instruction gets executed again.
459 */
460 regs->gr[31] -= 8; /* delayed branching */
461
462 /* Get assembler opcode of code in delay branch */
463 uaddr = (unsigned int *) ((regs->gr[31] & ~3) + 4);
464 err = get_user(opcode, uaddr);
465 if (err)
466 return;
467
468 /* Check if delay branch uses "ldi int,%r20" */
469 if ((opcode & 0xffff0000) == 0x34140000)
470 return; /* everything ok, just return */
471
472 /* Check if delay branch uses "nop" */
473 if (opcode == INSN_NOP)
474 return;
475
476 /* Check if delay branch uses "copy %rX,%r20" */
477 if ((opcode & 0xffe0ffff) == 0x08000254) {
478 source_reg = (opcode >> 16) & 31;
479 regs->gr[source_reg] = regs->gr[20];
480 return;
481 }
482
483 pr_warn("syscall restart: %s (pid %d): unexpected opcode 0x%08x\n",
484 current->comm, task_pid_nr(current), opcode);
485 }
486
487 static inline void
syscall_restart(struct pt_regs * regs,struct k_sigaction * ka)488 syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
489 {
490 if (regs->orig_r28)
491 return;
492 regs->orig_r28 = 1; /* no more restarts */
493 /* Check the return code */
494 switch (regs->gr[28]) {
495 case -ERESTART_RESTARTBLOCK:
496 case -ERESTARTNOHAND:
497 DBG(1,"ERESTARTNOHAND: returning -EINTR\n");
498 regs->gr[28] = -EINTR;
499 break;
500
501 case -ERESTARTSYS:
502 if (!(ka->sa.sa_flags & SA_RESTART)) {
503 DBG(1,"ERESTARTSYS: putting -EINTR\n");
504 regs->gr[28] = -EINTR;
505 break;
506 }
507 /* fallthrough */
508 case -ERESTARTNOINTR:
509 check_syscallno_in_delay_branch(regs);
510 break;
511 }
512 }
513
514 static inline void
insert_restart_trampoline(struct pt_regs * regs)515 insert_restart_trampoline(struct pt_regs *regs)
516 {
517 if (regs->orig_r28)
518 return;
519 regs->orig_r28 = 1; /* no more restarts */
520 switch(regs->gr[28]) {
521 case -ERESTART_RESTARTBLOCK: {
522 /* Restart the system call - no handlers present */
523 unsigned int *usp = (unsigned int *)regs->gr[30];
524 unsigned long start = (unsigned long) &usp[2];
525 unsigned long end = (unsigned long) &usp[5];
526 long err = 0;
527
528 /* Setup a trampoline to restart the syscall
529 * with __NR_restart_syscall
530 *
531 * 0: <return address (orig r31)>
532 * 4: <2nd half for 64-bit>
533 * 8: ldw 0(%sp), %r31
534 * 12: be 0x100(%sr2, %r0)
535 * 16: ldi __NR_restart_syscall, %r20
536 */
537 #ifdef CONFIG_64BIT
538 err |= put_user(regs->gr[31] >> 32, &usp[0]);
539 err |= put_user(regs->gr[31] & 0xffffffff, &usp[1]);
540 err |= put_user(0x0fc010df, &usp[2]);
541 #else
542 err |= put_user(regs->gr[31], &usp[0]);
543 err |= put_user(0x0fc0109f, &usp[2]);
544 #endif
545 err |= put_user(0xe0008200, &usp[3]);
546 err |= put_user(0x34140000, &usp[4]);
547
548 WARN_ON(err);
549
550 /* flush data/instruction cache for new insns */
551 flush_user_dcache_range_asm(start, end);
552 flush_user_icache_range_asm(start, end);
553
554 regs->gr[31] = regs->gr[30] + 8;
555 return;
556 }
557 case -ERESTARTNOHAND:
558 case -ERESTARTSYS:
559 case -ERESTARTNOINTR:
560 check_syscallno_in_delay_branch(regs);
561 return;
562 default:
563 break;
564 }
565 }
566
567 /*
568 * Note that 'init' is a special process: it doesn't get signals it doesn't
569 * want to handle. Thus you cannot kill init even with a SIGKILL even by
570 * mistake.
571 *
572 * We need to be able to restore the syscall arguments (r21-r26) to
573 * restart syscalls. Thus, the syscall path should save them in the
574 * pt_regs structure (it's okay to do so since they are caller-save
575 * registers). As noted below, the syscall number gets restored for
576 * us due to the magic of delayed branching.
577 */
578 asmlinkage void
do_signal(struct pt_regs * regs,long in_syscall)579 do_signal(struct pt_regs *regs, long in_syscall)
580 {
581 struct ksignal ksig;
582
583 DBG(1,"\ndo_signal: regs=0x%p, sr7 %#lx, in_syscall=%d\n",
584 regs, regs->sr[7], in_syscall);
585
586 if (get_signal(&ksig)) {
587 DBG(3,"do_signal: signr = %d, regs->gr[28] = %ld\n", signr, regs->gr[28]);
588 /* Restart a system call if necessary. */
589 if (in_syscall)
590 syscall_restart(regs, &ksig.ka);
591
592 handle_signal(&ksig, regs, in_syscall);
593 return;
594 }
595
596 /* Did we come from a system call? */
597 if (in_syscall)
598 insert_restart_trampoline(regs);
599
600 DBG(1,"do_signal: Exit (not delivered), regs->gr[28] = %ld\n",
601 regs->gr[28]);
602
603 restore_saved_sigmask();
604 }
605
do_notify_resume(struct pt_regs * regs,long in_syscall)606 void do_notify_resume(struct pt_regs *regs, long in_syscall)
607 {
608 if (test_thread_flag(TIF_SIGPENDING))
609 do_signal(regs, in_syscall);
610
611 if (test_thread_flag(TIF_NOTIFY_RESUME)) {
612 clear_thread_flag(TIF_NOTIFY_RESUME);
613 tracehook_notify_resume(regs);
614 }
615 }
616
