signal.c 19 KB

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  1. /*
  2. * Architecture-specific signal handling support.
  3. *
  4. * Copyright (C) 1999-2004 Hewlett-Packard Co
  5. * David Mosberger-Tang <davidm@hpl.hp.com>
  6. *
  7. * Derived from i386 and Alpha versions.
  8. */
  9. #include <linux/errno.h>
  10. #include <linux/kernel.h>
  11. #include <linux/mm.h>
  12. #include <linux/ptrace.h>
  13. #include <linux/sched.h>
  14. #include <linux/signal.h>
  15. #include <linux/smp.h>
  16. #include <linux/smp_lock.h>
  17. #include <linux/stddef.h>
  18. #include <linux/tty.h>
  19. #include <linux/binfmts.h>
  20. #include <linux/unistd.h>
  21. #include <linux/wait.h>
  22. #include <asm/ia32.h>
  23. #include <asm/intrinsics.h>
  24. #include <asm/uaccess.h>
  25. #include <asm/rse.h>
  26. #include <asm/sigcontext.h>
  27. #include "sigframe.h"
  28. #define DEBUG_SIG 0
  29. #define STACK_ALIGN 16 /* minimal alignment for stack pointer */
  30. #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
  31. #if _NSIG_WORDS > 1
  32. # define PUT_SIGSET(k,u) __copy_to_user((u)->sig, (k)->sig, sizeof(sigset_t))
  33. # define GET_SIGSET(k,u) __copy_from_user((k)->sig, (u)->sig, sizeof(sigset_t))
  34. #else
  35. # define PUT_SIGSET(k,u) __put_user((k)->sig[0], &(u)->sig[0])
  36. # define GET_SIGSET(k,u) __get_user((k)->sig[0], &(u)->sig[0])
  37. #endif
  38. long
  39. ia64_rt_sigsuspend (sigset_t __user *uset, size_t sigsetsize, struct sigscratch *scr)
  40. {
  41. sigset_t oldset, set;
  42. /* XXX: Don't preclude handling different sized sigset_t's. */
  43. if (sigsetsize != sizeof(sigset_t))
  44. return -EINVAL;
  45. if (!access_ok(VERIFY_READ, uset, sigsetsize))
  46. return -EFAULT;
  47. if (GET_SIGSET(&set, uset))
  48. return -EFAULT;
  49. sigdelsetmask(&set, ~_BLOCKABLE);
  50. spin_lock_irq(&current->sighand->siglock);
  51. {
  52. oldset = current->blocked;
  53. current->blocked = set;
  54. recalc_sigpending();
  55. }
  56. spin_unlock_irq(&current->sighand->siglock);
  57. /*
  58. * The return below usually returns to the signal handler. We need to
  59. * pre-set the correct error code here to ensure that the right values
  60. * get saved in sigcontext by ia64_do_signal.
  61. */
  62. scr->pt.r8 = EINTR;
  63. scr->pt.r10 = -1;
  64. while (1) {
  65. current->state = TASK_INTERRUPTIBLE;
  66. schedule();
  67. if (ia64_do_signal(&oldset, scr, 1))
  68. return -EINTR;
  69. }
  70. }
  71. asmlinkage long
  72. sys_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, long arg2,
  73. long arg3, long arg4, long arg5, long arg6, long arg7,
  74. struct pt_regs regs)
  75. {
  76. return do_sigaltstack(uss, uoss, regs.r12);
  77. }
  78. static long
  79. restore_sigcontext (struct sigcontext __user *sc, struct sigscratch *scr)
  80. {
  81. unsigned long ip, flags, nat, um, cfm, rsc;
  82. long err;
  83. /* Always make any pending restarted system calls return -EINTR */
  84. current_thread_info()->restart_block.fn = do_no_restart_syscall;
  85. /* restore scratch that always needs gets updated during signal delivery: */
  86. err = __get_user(flags, &sc->sc_flags);
  87. err |= __get_user(nat, &sc->sc_nat);
  88. err |= __get_user(ip, &sc->sc_ip); /* instruction pointer */
  89. err |= __get_user(cfm, &sc->sc_cfm);
  90. err |= __get_user(um, &sc->sc_um); /* user mask */
  91. err |= __get_user(rsc, &sc->sc_ar_rsc);
  92. err |= __get_user(scr->pt.ar_unat, &sc->sc_ar_unat);
  93. err |= __get_user(scr->pt.ar_fpsr, &sc->sc_ar_fpsr);
  94. err |= __get_user(scr->pt.ar_pfs, &sc->sc_ar_pfs);
  95. err |= __get_user(scr->pt.pr, &sc->sc_pr); /* predicates */
  96. err |= __get_user(scr->pt.b0, &sc->sc_br[0]); /* b0 (rp) */
  97. err |= __get_user(scr->pt.b6, &sc->sc_br[6]); /* b6 */
  98. err |= __copy_from_user(&scr->pt.r1, &sc->sc_gr[1], 8); /* r1 */
  99. err |= __copy_from_user(&scr->pt.r8, &sc->sc_gr[8], 4*8); /* r8-r11 */
  100. err |= __copy_from_user(&scr->pt.r12, &sc->sc_gr[12], 2*8); /* r12-r13 */
  101. err |= __copy_from_user(&scr->pt.r15, &sc->sc_gr[15], 8); /* r15 */
  102. scr->pt.cr_ifs = cfm | (1UL << 63);
  103. scr->pt.ar_rsc = rsc | (3 << 2); /* force PL3 */
  104. /* establish new instruction pointer: */
  105. scr->pt.cr_iip = ip & ~0x3UL;
  106. ia64_psr(&scr->pt)->ri = ip & 0x3;
  107. scr->pt.cr_ipsr = (scr->pt.cr_ipsr & ~IA64_PSR_UM) | (um & IA64_PSR_UM);
  108. scr->scratch_unat = ia64_put_scratch_nat_bits(&scr->pt, nat);
  109. if (!(flags & IA64_SC_FLAG_IN_SYSCALL)) {
  110. /* Restore most scratch-state only when not in syscall. */
  111. err |= __get_user(scr->pt.ar_ccv, &sc->sc_ar_ccv); /* ar.ccv */
  112. err |= __get_user(scr->pt.b7, &sc->sc_br[7]); /* b7 */
  113. err |= __get_user(scr->pt.r14, &sc->sc_gr[14]); /* r14 */
  114. err |= __copy_from_user(&scr->pt.ar_csd, &sc->sc_ar25, 2*8); /* ar.csd & ar.ssd */
  115. err |= __copy_from_user(&scr->pt.r2, &sc->sc_gr[2], 2*8); /* r2-r3 */
  116. err |= __copy_from_user(&scr->pt.r16, &sc->sc_gr[16], 16*8); /* r16-r31 */
  117. }
  118. if ((flags & IA64_SC_FLAG_FPH_VALID) != 0) {
  119. struct ia64_psr *psr = ia64_psr(&scr->pt);
  120. __copy_from_user(current->thread.fph, &sc->sc_fr[32], 96*16);
  121. psr->mfh = 0; /* drop signal handler's fph contents... */
  122. preempt_disable();
  123. if (psr->dfh)
  124. ia64_drop_fpu(current);
  125. else {
  126. /* We already own the local fph, otherwise psr->dfh wouldn't be 0. */
  127. __ia64_load_fpu(current->thread.fph);
  128. ia64_set_local_fpu_owner(current);
  129. }
  130. preempt_enable();
  131. }
  132. return err;
  133. }
  134. int
  135. copy_siginfo_to_user (siginfo_t __user *to, siginfo_t *from)
  136. {
  137. if (!access_ok(VERIFY_WRITE, to, sizeof(siginfo_t)))
  138. return -EFAULT;
  139. if (from->si_code < 0) {
  140. if (__copy_to_user(to, from, sizeof(siginfo_t)))
  141. return -EFAULT;
  142. return 0;
  143. } else {
  144. int err;
  145. /*
  146. * If you change siginfo_t structure, please be sure this code is fixed
  147. * accordingly. It should never copy any pad contained in the structure
  148. * to avoid security leaks, but must copy the generic 3 ints plus the
  149. * relevant union member.
  150. */
  151. err = __put_user(from->si_signo, &to->si_signo);
  152. err |= __put_user(from->si_errno, &to->si_errno);
  153. err |= __put_user((short)from->si_code, &to->si_code);
  154. switch (from->si_code >> 16) {
  155. case __SI_FAULT >> 16:
  156. err |= __put_user(from->si_flags, &to->si_flags);
  157. err |= __put_user(from->si_isr, &to->si_isr);
  158. case __SI_POLL >> 16:
  159. err |= __put_user(from->si_addr, &to->si_addr);
  160. err |= __put_user(from->si_imm, &to->si_imm);
  161. break;
  162. case __SI_TIMER >> 16:
  163. err |= __put_user(from->si_tid, &to->si_tid);
  164. err |= __put_user(from->si_overrun, &to->si_overrun);
  165. err |= __put_user(from->si_ptr, &to->si_ptr);
  166. break;
  167. case __SI_RT >> 16: /* Not generated by the kernel as of now. */
  168. case __SI_MESGQ >> 16:
  169. err |= __put_user(from->si_uid, &to->si_uid);
  170. err |= __put_user(from->si_pid, &to->si_pid);
  171. err |= __put_user(from->si_ptr, &to->si_ptr);
  172. break;
  173. case __SI_CHLD >> 16:
  174. err |= __put_user(from->si_utime, &to->si_utime);
  175. err |= __put_user(from->si_stime, &to->si_stime);
  176. err |= __put_user(from->si_status, &to->si_status);
  177. default:
  178. err |= __put_user(from->si_uid, &to->si_uid);
  179. err |= __put_user(from->si_pid, &to->si_pid);
  180. break;
  181. }
  182. return err;
  183. }
  184. }
  185. long
  186. ia64_rt_sigreturn (struct sigscratch *scr)
  187. {
  188. extern char ia64_strace_leave_kernel, ia64_leave_kernel;
  189. struct sigcontext __user *sc;
  190. struct siginfo si;
  191. sigset_t set;
  192. long retval;
  193. sc = &((struct sigframe __user *) (scr->pt.r12 + 16))->sc;
  194. /*
  195. * When we return to the previously executing context, r8 and r10 have already
  196. * been setup the way we want them. Indeed, if the signal wasn't delivered while
  197. * in a system call, we must not touch r8 or r10 as otherwise user-level state
  198. * could be corrupted.
  199. */
  200. retval = (long) &ia64_leave_kernel;
  201. if (test_thread_flag(TIF_SYSCALL_TRACE)
  202. || test_thread_flag(TIF_SYSCALL_AUDIT))
  203. /*
  204. * strace expects to be notified after sigreturn returns even though the
  205. * context to which we return may not be in the middle of a syscall.
  206. * Thus, the return-value that strace displays for sigreturn is
  207. * meaningless.
  208. */
  209. retval = (long) &ia64_strace_leave_kernel;
  210. if (!access_ok(VERIFY_READ, sc, sizeof(*sc)))
  211. goto give_sigsegv;
  212. if (GET_SIGSET(&set, &sc->sc_mask))
  213. goto give_sigsegv;
  214. sigdelsetmask(&set, ~_BLOCKABLE);
  215. spin_lock_irq(&current->sighand->siglock);
  216. {
  217. current->blocked = set;
  218. recalc_sigpending();
  219. }
  220. spin_unlock_irq(&current->sighand->siglock);
  221. if (restore_sigcontext(sc, scr))
  222. goto give_sigsegv;
  223. #if DEBUG_SIG
  224. printk("SIG return (%s:%d): sp=%lx ip=%lx\n",
  225. current->comm, current->pid, scr->pt.r12, scr->pt.cr_iip);
  226. #endif
  227. /*
  228. * It is more difficult to avoid calling this function than to
  229. * call it and ignore errors.
  230. */
  231. do_sigaltstack(&sc->sc_stack, NULL, scr->pt.r12);
  232. return retval;
  233. give_sigsegv:
  234. si.si_signo = SIGSEGV;
  235. si.si_errno = 0;
  236. si.si_code = SI_KERNEL;
  237. si.si_pid = current->pid;
  238. si.si_uid = current->uid;
  239. si.si_addr = sc;
  240. force_sig_info(SIGSEGV, &si, current);
  241. return retval;
  242. }
  243. /*
  244. * This does just the minimum required setup of sigcontext.
  245. * Specifically, it only installs data that is either not knowable at
  246. * the user-level or that gets modified before execution in the
  247. * trampoline starts. Everything else is done at the user-level.
  248. */
  249. static long
  250. setup_sigcontext (struct sigcontext __user *sc, sigset_t *mask, struct sigscratch *scr)
  251. {
  252. unsigned long flags = 0, ifs, cfm, nat;
  253. long err;
  254. ifs = scr->pt.cr_ifs;
  255. if (on_sig_stack((unsigned long) sc))
  256. flags |= IA64_SC_FLAG_ONSTACK;
  257. if ((ifs & (1UL << 63)) == 0)
  258. /* if cr_ifs doesn't have the valid bit set, we got here through a syscall */
  259. flags |= IA64_SC_FLAG_IN_SYSCALL;
  260. cfm = ifs & ((1UL << 38) - 1);
  261. ia64_flush_fph(current);
  262. if ((current->thread.flags & IA64_THREAD_FPH_VALID)) {
  263. flags |= IA64_SC_FLAG_FPH_VALID;
  264. __copy_to_user(&sc->sc_fr[32], current->thread.fph, 96*16);
  265. }
  266. nat = ia64_get_scratch_nat_bits(&scr->pt, scr->scratch_unat);
  267. err = __put_user(flags, &sc->sc_flags);
  268. err |= __put_user(nat, &sc->sc_nat);
  269. err |= PUT_SIGSET(mask, &sc->sc_mask);
  270. err |= __put_user(cfm, &sc->sc_cfm);
  271. err |= __put_user(scr->pt.cr_ipsr & IA64_PSR_UM, &sc->sc_um);
  272. err |= __put_user(scr->pt.ar_rsc, &sc->sc_ar_rsc);
  273. err |= __put_user(scr->pt.ar_unat, &sc->sc_ar_unat); /* ar.unat */
  274. err |= __put_user(scr->pt.ar_fpsr, &sc->sc_ar_fpsr); /* ar.fpsr */
  275. err |= __put_user(scr->pt.ar_pfs, &sc->sc_ar_pfs);
  276. err |= __put_user(scr->pt.pr, &sc->sc_pr); /* predicates */
  277. err |= __put_user(scr->pt.b0, &sc->sc_br[0]); /* b0 (rp) */
  278. err |= __put_user(scr->pt.b6, &sc->sc_br[6]); /* b6 */
  279. err |= __copy_to_user(&sc->sc_gr[1], &scr->pt.r1, 8); /* r1 */
  280. err |= __copy_to_user(&sc->sc_gr[8], &scr->pt.r8, 4*8); /* r8-r11 */
  281. err |= __copy_to_user(&sc->sc_gr[12], &scr->pt.r12, 2*8); /* r12-r13 */
  282. err |= __copy_to_user(&sc->sc_gr[15], &scr->pt.r15, 8); /* r15 */
  283. err |= __put_user(scr->pt.cr_iip + ia64_psr(&scr->pt)->ri, &sc->sc_ip);
  284. if (flags & IA64_SC_FLAG_IN_SYSCALL) {
  285. /* Clear scratch registers if the signal interrupted a system call. */
  286. err |= __put_user(0, &sc->sc_ar_ccv); /* ar.ccv */
  287. err |= __put_user(0, &sc->sc_br[7]); /* b7 */
  288. err |= __put_user(0, &sc->sc_gr[14]); /* r14 */
  289. err |= __clear_user(&sc->sc_ar25, 2*8); /* ar.csd & ar.ssd */
  290. err |= __clear_user(&sc->sc_gr[2], 2*8); /* r2-r3 */
  291. err |= __clear_user(&sc->sc_gr[16], 16*8); /* r16-r31 */
  292. } else {
  293. /* Copy scratch regs to sigcontext if the signal didn't interrupt a syscall. */
  294. err |= __put_user(scr->pt.ar_ccv, &sc->sc_ar_ccv); /* ar.ccv */
  295. err |= __put_user(scr->pt.b7, &sc->sc_br[7]); /* b7 */
  296. err |= __put_user(scr->pt.r14, &sc->sc_gr[14]); /* r14 */
  297. err |= __copy_to_user(&sc->sc_ar25, &scr->pt.ar_csd, 2*8); /* ar.csd & ar.ssd */
  298. err |= __copy_to_user(&sc->sc_gr[2], &scr->pt.r2, 2*8); /* r2-r3 */
  299. err |= __copy_to_user(&sc->sc_gr[16], &scr->pt.r16, 16*8); /* r16-r31 */
  300. }
  301. return err;
  302. }
  303. /*
  304. * Check whether the register-backing store is already on the signal stack.
  305. */
  306. static inline int
  307. rbs_on_sig_stack (unsigned long bsp)
  308. {
  309. return (bsp - current->sas_ss_sp < current->sas_ss_size);
  310. }
  311. static long
  312. force_sigsegv_info (int sig, void __user *addr)
  313. {
  314. unsigned long flags;
  315. struct siginfo si;
  316. if (sig == SIGSEGV) {
  317. /*
  318. * Acquiring siglock around the sa_handler-update is almost
  319. * certainly overkill, but this isn't a
  320. * performance-critical path and I'd rather play it safe
  321. * here than having to debug a nasty race if and when
  322. * something changes in kernel/signal.c that would make it
  323. * no longer safe to modify sa_handler without holding the
  324. * lock.
  325. */
  326. spin_lock_irqsave(&current->sighand->siglock, flags);
  327. current->sighand->action[sig - 1].sa.sa_handler = SIG_DFL;
  328. spin_unlock_irqrestore(&current->sighand->siglock, flags);
  329. }
  330. si.si_signo = SIGSEGV;
  331. si.si_errno = 0;
  332. si.si_code = SI_KERNEL;
  333. si.si_pid = current->pid;
  334. si.si_uid = current->uid;
  335. si.si_addr = addr;
  336. force_sig_info(SIGSEGV, &si, current);
  337. return 0;
  338. }
  339. static long
  340. setup_frame (int sig, struct k_sigaction *ka, siginfo_t *info, sigset_t *set,
  341. struct sigscratch *scr)
  342. {
  343. extern char __kernel_sigtramp[];
  344. unsigned long tramp_addr, new_rbs = 0, new_sp;
  345. struct sigframe __user *frame;
  346. long err;
  347. new_sp = scr->pt.r12;
  348. tramp_addr = (unsigned long) __kernel_sigtramp;
  349. if ((ka->sa.sa_flags & SA_ONSTACK) && sas_ss_flags(new_sp) == 0) {
  350. new_sp = current->sas_ss_sp + current->sas_ss_size;
  351. /*
  352. * We need to check for the register stack being on the signal stack
  353. * separately, because it's switched separately (memory stack is switched
  354. * in the kernel, register stack is switched in the signal trampoline).
  355. */
  356. if (!rbs_on_sig_stack(scr->pt.ar_bspstore))
  357. new_rbs = (current->sas_ss_sp + sizeof(long) - 1) & ~(sizeof(long) - 1);
  358. }
  359. frame = (void __user *) ((new_sp - sizeof(*frame)) & -STACK_ALIGN);
  360. if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
  361. return force_sigsegv_info(sig, frame);
  362. err = __put_user(sig, &frame->arg0);
  363. err |= __put_user(&frame->info, &frame->arg1);
  364. err |= __put_user(&frame->sc, &frame->arg2);
  365. err |= __put_user(new_rbs, &frame->sc.sc_rbs_base);
  366. err |= __put_user(0, &frame->sc.sc_loadrs); /* initialize to zero */
  367. err |= __put_user(ka->sa.sa_handler, &frame->handler);
  368. err |= copy_siginfo_to_user(&frame->info, info);
  369. err |= __put_user(current->sas_ss_sp, &frame->sc.sc_stack.ss_sp);
  370. err |= __put_user(current->sas_ss_size, &frame->sc.sc_stack.ss_size);
  371. err |= __put_user(sas_ss_flags(scr->pt.r12), &frame->sc.sc_stack.ss_flags);
  372. err |= setup_sigcontext(&frame->sc, set, scr);
  373. if (unlikely(err))
  374. return force_sigsegv_info(sig, frame);
  375. scr->pt.r12 = (unsigned long) frame - 16; /* new stack pointer */
  376. scr->pt.ar_fpsr = FPSR_DEFAULT; /* reset fpsr for signal handler */
  377. scr->pt.cr_iip = tramp_addr;
  378. ia64_psr(&scr->pt)->ri = 0; /* start executing in first slot */
  379. ia64_psr(&scr->pt)->be = 0; /* force little-endian byte-order */
  380. /*
  381. * Force the interruption function mask to zero. This has no effect when a
  382. * system-call got interrupted by a signal (since, in that case, scr->pt_cr_ifs is
  383. * ignored), but it has the desirable effect of making it possible to deliver a
  384. * signal with an incomplete register frame (which happens when a mandatory RSE
  385. * load faults). Furthermore, it has no negative effect on the getting the user's
  386. * dirty partition preserved, because that's governed by scr->pt.loadrs.
  387. */
  388. scr->pt.cr_ifs = (1UL << 63);
  389. /*
  390. * Note: this affects only the NaT bits of the scratch regs (the ones saved in
  391. * pt_regs), which is exactly what we want.
  392. */
  393. scr->scratch_unat = 0; /* ensure NaT bits of r12 is clear */
  394. #if DEBUG_SIG
  395. printk("SIG deliver (%s:%d): sig=%d sp=%lx ip=%lx handler=%p\n",
  396. current->comm, current->pid, sig, scr->pt.r12, frame->sc.sc_ip, frame->handler);
  397. #endif
  398. return 1;
  399. }
  400. static long
  401. handle_signal (unsigned long sig, struct k_sigaction *ka, siginfo_t *info, sigset_t *oldset,
  402. struct sigscratch *scr)
  403. {
  404. if (IS_IA32_PROCESS(&scr->pt)) {
  405. /* send signal to IA-32 process */
  406. if (!ia32_setup_frame1(sig, ka, info, oldset, &scr->pt))
  407. return 0;
  408. } else
  409. /* send signal to IA-64 process */
  410. if (!setup_frame(sig, ka, info, oldset, scr))
  411. return 0;
  412. spin_lock_irq(&current->sighand->siglock);
  413. sigorsets(&current->blocked, &current->blocked, &ka->sa.sa_mask);
  414. if (!(ka->sa.sa_flags & SA_NODEFER))
  415. sigaddset(&current->blocked, sig);
  416. recalc_sigpending();
  417. spin_unlock_irq(&current->sighand->siglock);
  418. return 1;
  419. }
  420. /*
  421. * Note that `init' is a special process: it doesn't get signals it doesn't want to
  422. * handle. Thus you cannot kill init even with a SIGKILL even by mistake.
  423. */
  424. long
  425. ia64_do_signal (sigset_t *oldset, struct sigscratch *scr, long in_syscall)
  426. {
  427. struct k_sigaction ka;
  428. siginfo_t info;
  429. long restart = in_syscall;
  430. long errno = scr->pt.r8;
  431. # define ERR_CODE(c) (IS_IA32_PROCESS(&scr->pt) ? -(c) : (c))
  432. /*
  433. * In the ia64_leave_kernel code path, we want the common case to go fast, which
  434. * is why we may in certain cases get here from kernel mode. Just return without
  435. * doing anything if so.
  436. */
  437. if (!user_mode(&scr->pt))
  438. return 0;
  439. if (!oldset)
  440. oldset = &current->blocked;
  441. /*
  442. * This only loops in the rare cases of handle_signal() failing, in which case we
  443. * need to push through a forced SIGSEGV.
  444. */
  445. while (1) {
  446. int signr = get_signal_to_deliver(&info, &ka, &scr->pt, NULL);
  447. /*
  448. * get_signal_to_deliver() may have run a debugger (via notify_parent())
  449. * and the debugger may have modified the state (e.g., to arrange for an
  450. * inferior call), thus it's important to check for restarting _after_
  451. * get_signal_to_deliver().
  452. */
  453. if (IS_IA32_PROCESS(&scr->pt)) {
  454. if (in_syscall) {
  455. if (errno >= 0)
  456. restart = 0;
  457. else
  458. errno = -errno;
  459. }
  460. } else if ((long) scr->pt.r10 != -1)
  461. /*
  462. * A system calls has to be restarted only if one of the error codes
  463. * ERESTARTNOHAND, ERESTARTSYS, or ERESTARTNOINTR is returned. If r10
  464. * isn't -1 then r8 doesn't hold an error code and we don't need to
  465. * restart the syscall, so we can clear the "restart" flag here.
  466. */
  467. restart = 0;
  468. if (signr <= 0)
  469. break;
  470. if (unlikely(restart)) {
  471. switch (errno) {
  472. case ERESTART_RESTARTBLOCK:
  473. case ERESTARTNOHAND:
  474. scr->pt.r8 = ERR_CODE(EINTR);
  475. /* note: scr->pt.r10 is already -1 */
  476. break;
  477. case ERESTARTSYS:
  478. if ((ka.sa.sa_flags & SA_RESTART) == 0) {
  479. scr->pt.r8 = ERR_CODE(EINTR);
  480. /* note: scr->pt.r10 is already -1 */
  481. break;
  482. }
  483. case ERESTARTNOINTR:
  484. if (IS_IA32_PROCESS(&scr->pt)) {
  485. scr->pt.r8 = scr->pt.r1;
  486. scr->pt.cr_iip -= 2;
  487. } else
  488. ia64_decrement_ip(&scr->pt);
  489. restart = 0; /* don't restart twice if handle_signal() fails... */
  490. }
  491. }
  492. /*
  493. * Whee! Actually deliver the signal. If the delivery failed, we need to
  494. * continue to iterate in this loop so we can deliver the SIGSEGV...
  495. */
  496. if (handle_signal(signr, &ka, &info, oldset, scr))
  497. return 1;
  498. }
  499. /* Did we come from a system call? */
  500. if (restart) {
  501. /* Restart the system call - no handlers present */
  502. if (errno == ERESTARTNOHAND || errno == ERESTARTSYS || errno == ERESTARTNOINTR
  503. || errno == ERESTART_RESTARTBLOCK)
  504. {
  505. if (IS_IA32_PROCESS(&scr->pt)) {
  506. scr->pt.r8 = scr->pt.r1;
  507. scr->pt.cr_iip -= 2;
  508. if (errno == ERESTART_RESTARTBLOCK)
  509. scr->pt.r8 = 0; /* x86 version of __NR_restart_syscall */
  510. } else {
  511. /*
  512. * Note: the syscall number is in r15 which is saved in
  513. * pt_regs so all we need to do here is adjust ip so that
  514. * the "break" instruction gets re-executed.
  515. */
  516. ia64_decrement_ip(&scr->pt);
  517. if (errno == ERESTART_RESTARTBLOCK)
  518. scr->pt.r15 = __NR_restart_syscall;
  519. }
  520. }
  521. }
  522. return 0;
  523. }