722 lines
19 KiB
C
722 lines
19 KiB
C
/*
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* linux/arch/arm/kernel/signal.c
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*
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* Copyright (C) 1995-2002 Russell King
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/config.h>
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#include <linux/errno.h>
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#include <linux/signal.h>
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#include <linux/ptrace.h>
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#include <linux/personality.h>
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#include <asm/cacheflush.h>
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#include <asm/ucontext.h>
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#include <asm/uaccess.h>
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#include <asm/unistd.h>
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#include "ptrace.h"
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#include "signal.h"
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#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
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/*
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* For ARM syscalls, we encode the syscall number into the instruction.
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*/
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#define SWI_SYS_SIGRETURN (0xef000000|(__NR_sigreturn))
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#define SWI_SYS_RT_SIGRETURN (0xef000000|(__NR_rt_sigreturn))
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/*
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* With EABI, the syscall number has to be loaded into r7.
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*/
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#define MOV_R7_NR_SIGRETURN (0xe3a07000 | (__NR_sigreturn - __NR_SYSCALL_BASE))
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#define MOV_R7_NR_RT_SIGRETURN (0xe3a07000 | (__NR_rt_sigreturn - __NR_SYSCALL_BASE))
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/*
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* For Thumb syscalls, we pass the syscall number via r7. We therefore
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* need two 16-bit instructions.
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*/
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#define SWI_THUMB_SIGRETURN (0xdf00 << 16 | 0x2700 | (__NR_sigreturn - __NR_SYSCALL_BASE))
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#define SWI_THUMB_RT_SIGRETURN (0xdf00 << 16 | 0x2700 | (__NR_rt_sigreturn - __NR_SYSCALL_BASE))
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const unsigned long sigreturn_codes[7] = {
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MOV_R7_NR_SIGRETURN, SWI_SYS_SIGRETURN, SWI_THUMB_SIGRETURN,
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MOV_R7_NR_RT_SIGRETURN, SWI_SYS_RT_SIGRETURN, SWI_THUMB_RT_SIGRETURN,
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};
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static int do_signal(sigset_t *oldset, struct pt_regs * regs, int syscall);
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/*
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* atomically swap in the new signal mask, and wait for a signal.
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*/
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asmlinkage int sys_sigsuspend(int restart, unsigned long oldmask, old_sigset_t mask, struct pt_regs *regs)
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{
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sigset_t saveset;
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mask &= _BLOCKABLE;
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spin_lock_irq(¤t->sighand->siglock);
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saveset = current->blocked;
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siginitset(¤t->blocked, mask);
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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regs->ARM_r0 = -EINTR;
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while (1) {
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current->state = TASK_INTERRUPTIBLE;
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schedule();
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if (do_signal(&saveset, regs, 0))
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return regs->ARM_r0;
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}
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}
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asmlinkage int
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sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize, struct pt_regs *regs)
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{
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sigset_t saveset, newset;
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/* XXX: Don't preclude handling different sized sigset_t's. */
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if (sigsetsize != sizeof(sigset_t))
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return -EINVAL;
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if (copy_from_user(&newset, unewset, sizeof(newset)))
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return -EFAULT;
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sigdelsetmask(&newset, ~_BLOCKABLE);
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spin_lock_irq(¤t->sighand->siglock);
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saveset = current->blocked;
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current->blocked = newset;
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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regs->ARM_r0 = -EINTR;
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while (1) {
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current->state = TASK_INTERRUPTIBLE;
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schedule();
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if (do_signal(&saveset, regs, 0))
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return regs->ARM_r0;
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}
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}
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asmlinkage int
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sys_sigaction(int sig, const struct old_sigaction __user *act,
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struct old_sigaction __user *oact)
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{
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struct k_sigaction new_ka, old_ka;
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int ret;
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if (act) {
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old_sigset_t mask;
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if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
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__get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
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__get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
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return -EFAULT;
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__get_user(new_ka.sa.sa_flags, &act->sa_flags);
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__get_user(mask, &act->sa_mask);
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siginitset(&new_ka.sa.sa_mask, mask);
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}
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ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
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if (!ret && oact) {
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if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
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__put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
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__put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
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return -EFAULT;
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__put_user(old_ka.sa.sa_flags, &oact->sa_flags);
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__put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
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}
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return ret;
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}
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#ifdef CONFIG_IWMMXT
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/* iwmmxt_area is 0x98 bytes long, preceeded by 8 bytes of signature */
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#define IWMMXT_STORAGE_SIZE (0x98 + 8)
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#define IWMMXT_MAGIC0 0x12ef842a
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#define IWMMXT_MAGIC1 0x1c07ca71
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struct iwmmxt_sigframe {
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unsigned long magic0;
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unsigned long magic1;
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unsigned long storage[0x98/4];
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};
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static int preserve_iwmmxt_context(struct iwmmxt_sigframe *frame)
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{
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char kbuf[sizeof(*frame) + 8];
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struct iwmmxt_sigframe *kframe;
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/* the iWMMXt context must be 64 bit aligned */
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kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7);
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kframe->magic0 = IWMMXT_MAGIC0;
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kframe->magic1 = IWMMXT_MAGIC1;
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iwmmxt_task_copy(current_thread_info(), &kframe->storage);
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return __copy_to_user(frame, kframe, sizeof(*frame));
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}
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static int restore_iwmmxt_context(struct iwmmxt_sigframe *frame)
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{
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char kbuf[sizeof(*frame) + 8];
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struct iwmmxt_sigframe *kframe;
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/* the iWMMXt context must be 64 bit aligned */
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kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7);
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if (__copy_from_user(kframe, frame, sizeof(*frame)))
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return -1;
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if (kframe->magic0 != IWMMXT_MAGIC0 ||
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kframe->magic1 != IWMMXT_MAGIC1)
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return -1;
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iwmmxt_task_restore(current_thread_info(), &kframe->storage);
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return 0;
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}
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#endif
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/*
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* Auxiliary signal frame. This saves stuff like FP state.
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* The layout of this structure is not part of the user ABI.
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*/
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struct aux_sigframe {
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#ifdef CONFIG_IWMMXT
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struct iwmmxt_sigframe iwmmxt;
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#endif
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#ifdef CONFIG_VFP
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union vfp_state vfp;
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#endif
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};
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/*
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* Do a signal return; undo the signal stack. These are aligned to 64-bit.
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*/
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struct sigframe {
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struct sigcontext sc;
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unsigned long extramask[_NSIG_WORDS-1];
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unsigned long retcode[2];
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struct aux_sigframe aux __attribute__((aligned(8)));
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};
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struct rt_sigframe {
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struct siginfo __user *pinfo;
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void __user *puc;
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struct siginfo info;
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struct ucontext uc;
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unsigned long retcode[2];
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struct aux_sigframe aux __attribute__((aligned(8)));
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};
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static int
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restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
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struct aux_sigframe __user *aux)
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{
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int err = 0;
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__get_user_error(regs->ARM_r0, &sc->arm_r0, err);
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__get_user_error(regs->ARM_r1, &sc->arm_r1, err);
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__get_user_error(regs->ARM_r2, &sc->arm_r2, err);
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__get_user_error(regs->ARM_r3, &sc->arm_r3, err);
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__get_user_error(regs->ARM_r4, &sc->arm_r4, err);
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__get_user_error(regs->ARM_r5, &sc->arm_r5, err);
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__get_user_error(regs->ARM_r6, &sc->arm_r6, err);
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__get_user_error(regs->ARM_r7, &sc->arm_r7, err);
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__get_user_error(regs->ARM_r8, &sc->arm_r8, err);
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__get_user_error(regs->ARM_r9, &sc->arm_r9, err);
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__get_user_error(regs->ARM_r10, &sc->arm_r10, err);
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__get_user_error(regs->ARM_fp, &sc->arm_fp, err);
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__get_user_error(regs->ARM_ip, &sc->arm_ip, err);
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__get_user_error(regs->ARM_sp, &sc->arm_sp, err);
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__get_user_error(regs->ARM_lr, &sc->arm_lr, err);
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__get_user_error(regs->ARM_pc, &sc->arm_pc, err);
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__get_user_error(regs->ARM_cpsr, &sc->arm_cpsr, err);
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err |= !valid_user_regs(regs);
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#ifdef CONFIG_IWMMXT
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if (err == 0 && test_thread_flag(TIF_USING_IWMMXT))
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err |= restore_iwmmxt_context(&aux->iwmmxt);
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#endif
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#ifdef CONFIG_VFP
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// if (err == 0)
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// err |= vfp_restore_state(&aux->vfp);
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#endif
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return err;
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}
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asmlinkage int sys_sigreturn(struct pt_regs *regs)
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{
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struct sigframe __user *frame;
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sigset_t set;
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/* Always make any pending restarted system calls return -EINTR */
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current_thread_info()->restart_block.fn = do_no_restart_syscall;
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/*
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* Since we stacked the signal on a 64-bit boundary,
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* then 'sp' should be word aligned here. If it's
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* not, then the user is trying to mess with us.
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*/
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if (regs->ARM_sp & 7)
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goto badframe;
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frame = (struct sigframe __user *)regs->ARM_sp;
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if (!access_ok(VERIFY_READ, frame, sizeof (*frame)))
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goto badframe;
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if (__get_user(set.sig[0], &frame->sc.oldmask)
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|| (_NSIG_WORDS > 1
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&& __copy_from_user(&set.sig[1], &frame->extramask,
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sizeof(frame->extramask))))
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goto badframe;
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sigdelsetmask(&set, ~_BLOCKABLE);
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spin_lock_irq(¤t->sighand->siglock);
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current->blocked = set;
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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if (restore_sigcontext(regs, &frame->sc, &frame->aux))
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goto badframe;
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/* Send SIGTRAP if we're single-stepping */
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if (current->ptrace & PT_SINGLESTEP) {
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ptrace_cancel_bpt(current);
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send_sig(SIGTRAP, current, 1);
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}
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return regs->ARM_r0;
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badframe:
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force_sig(SIGSEGV, current);
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return 0;
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}
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asmlinkage int sys_rt_sigreturn(struct pt_regs *regs)
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{
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struct rt_sigframe __user *frame;
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sigset_t set;
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/* Always make any pending restarted system calls return -EINTR */
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current_thread_info()->restart_block.fn = do_no_restart_syscall;
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/*
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* Since we stacked the signal on a 64-bit boundary,
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* then 'sp' should be word aligned here. If it's
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* not, then the user is trying to mess with us.
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*/
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if (regs->ARM_sp & 7)
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goto badframe;
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frame = (struct rt_sigframe __user *)regs->ARM_sp;
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if (!access_ok(VERIFY_READ, frame, sizeof (*frame)))
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goto badframe;
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if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
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goto badframe;
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sigdelsetmask(&set, ~_BLOCKABLE);
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spin_lock_irq(¤t->sighand->siglock);
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current->blocked = set;
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &frame->aux))
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goto badframe;
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if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->ARM_sp) == -EFAULT)
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goto badframe;
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/* Send SIGTRAP if we're single-stepping */
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if (current->ptrace & PT_SINGLESTEP) {
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ptrace_cancel_bpt(current);
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send_sig(SIGTRAP, current, 1);
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}
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return regs->ARM_r0;
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badframe:
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force_sig(SIGSEGV, current);
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return 0;
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}
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static int
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setup_sigcontext(struct sigcontext __user *sc, struct aux_sigframe __user *aux,
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struct pt_regs *regs, unsigned long mask)
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{
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int err = 0;
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__put_user_error(regs->ARM_r0, &sc->arm_r0, err);
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__put_user_error(regs->ARM_r1, &sc->arm_r1, err);
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__put_user_error(regs->ARM_r2, &sc->arm_r2, err);
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__put_user_error(regs->ARM_r3, &sc->arm_r3, err);
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__put_user_error(regs->ARM_r4, &sc->arm_r4, err);
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__put_user_error(regs->ARM_r5, &sc->arm_r5, err);
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__put_user_error(regs->ARM_r6, &sc->arm_r6, err);
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__put_user_error(regs->ARM_r7, &sc->arm_r7, err);
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__put_user_error(regs->ARM_r8, &sc->arm_r8, err);
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__put_user_error(regs->ARM_r9, &sc->arm_r9, err);
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__put_user_error(regs->ARM_r10, &sc->arm_r10, err);
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__put_user_error(regs->ARM_fp, &sc->arm_fp, err);
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__put_user_error(regs->ARM_ip, &sc->arm_ip, err);
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__put_user_error(regs->ARM_sp, &sc->arm_sp, err);
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__put_user_error(regs->ARM_lr, &sc->arm_lr, err);
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__put_user_error(regs->ARM_pc, &sc->arm_pc, err);
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__put_user_error(regs->ARM_cpsr, &sc->arm_cpsr, err);
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__put_user_error(current->thread.trap_no, &sc->trap_no, err);
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__put_user_error(current->thread.error_code, &sc->error_code, err);
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__put_user_error(current->thread.address, &sc->fault_address, err);
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__put_user_error(mask, &sc->oldmask, err);
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#ifdef CONFIG_IWMMXT
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if (err == 0 && test_thread_flag(TIF_USING_IWMMXT))
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err |= preserve_iwmmxt_context(&aux->iwmmxt);
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#endif
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#ifdef CONFIG_VFP
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// if (err == 0)
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// err |= vfp_save_state(&aux->vfp);
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#endif
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return err;
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}
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static inline void __user *
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get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, int framesize)
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{
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unsigned long sp = regs->ARM_sp;
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void __user *frame;
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/*
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* This is the X/Open sanctioned signal stack switching.
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*/
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if ((ka->sa.sa_flags & SA_ONSTACK) && !sas_ss_flags(sp))
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sp = current->sas_ss_sp + current->sas_ss_size;
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/*
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* ATPCS B01 mandates 8-byte alignment
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*/
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frame = (void __user *)((sp - framesize) & ~7);
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/*
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* Check that we can actually write to the signal frame.
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*/
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if (!access_ok(VERIFY_WRITE, frame, framesize))
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frame = NULL;
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return frame;
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}
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static int
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setup_return(struct pt_regs *regs, struct k_sigaction *ka,
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unsigned long __user *rc, void __user *frame, int usig)
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{
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unsigned long handler = (unsigned long)ka->sa.sa_handler;
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unsigned long retcode;
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int thumb = 0;
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unsigned long cpsr = regs->ARM_cpsr & ~PSR_f;
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/*
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* Maybe we need to deliver a 32-bit signal to a 26-bit task.
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*/
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if (ka->sa.sa_flags & SA_THIRTYTWO)
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cpsr = (cpsr & ~MODE_MASK) | USR_MODE;
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#ifdef CONFIG_ARM_THUMB
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if (elf_hwcap & HWCAP_THUMB) {
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/*
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* The LSB of the handler determines if we're going to
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* be using THUMB or ARM mode for this signal handler.
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*/
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thumb = handler & 1;
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if (thumb)
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cpsr |= PSR_T_BIT;
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else
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cpsr &= ~PSR_T_BIT;
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}
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#endif
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if (ka->sa.sa_flags & SA_RESTORER) {
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retcode = (unsigned long)ka->sa.sa_restorer;
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} else {
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unsigned int idx = thumb << 1;
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if (ka->sa.sa_flags & SA_SIGINFO)
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idx += 3;
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if (__put_user(sigreturn_codes[idx], rc) ||
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__put_user(sigreturn_codes[idx+1], rc+1))
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return 1;
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if (cpsr & MODE32_BIT) {
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/*
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* 32-bit code can use the new high-page
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* signal return code support.
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*/
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retcode = KERN_SIGRETURN_CODE + (idx << 2) + thumb;
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} else {
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/*
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* Ensure that the instruction cache sees
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* the return code written onto the stack.
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*/
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flush_icache_range((unsigned long)rc,
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(unsigned long)(rc + 2));
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retcode = ((unsigned long)rc) + thumb;
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}
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}
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regs->ARM_r0 = usig;
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regs->ARM_sp = (unsigned long)frame;
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regs->ARM_lr = retcode;
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regs->ARM_pc = handler;
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|
regs->ARM_cpsr = cpsr;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
setup_frame(int usig, struct k_sigaction *ka, sigset_t *set, struct pt_regs *regs)
|
|
{
|
|
struct sigframe __user *frame = get_sigframe(ka, regs, sizeof(*frame));
|
|
int err = 0;
|
|
|
|
if (!frame)
|
|
return 1;
|
|
|
|
err |= setup_sigcontext(&frame->sc, &frame->aux, regs, set->sig[0]);
|
|
|
|
if (_NSIG_WORDS > 1) {
|
|
err |= __copy_to_user(frame->extramask, &set->sig[1],
|
|
sizeof(frame->extramask));
|
|
}
|
|
|
|
if (err == 0)
|
|
err = setup_return(regs, ka, frame->retcode, frame, usig);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int
|
|
setup_rt_frame(int usig, struct k_sigaction *ka, siginfo_t *info,
|
|
sigset_t *set, struct pt_regs *regs)
|
|
{
|
|
struct rt_sigframe __user *frame = get_sigframe(ka, regs, sizeof(*frame));
|
|
stack_t stack;
|
|
int err = 0;
|
|
|
|
if (!frame)
|
|
return 1;
|
|
|
|
__put_user_error(&frame->info, &frame->pinfo, err);
|
|
__put_user_error(&frame->uc, &frame->puc, err);
|
|
err |= copy_siginfo_to_user(&frame->info, info);
|
|
|
|
__put_user_error(0, &frame->uc.uc_flags, err);
|
|
__put_user_error(NULL, &frame->uc.uc_link, err);
|
|
|
|
memset(&stack, 0, sizeof(stack));
|
|
stack.ss_sp = (void __user *)current->sas_ss_sp;
|
|
stack.ss_flags = sas_ss_flags(regs->ARM_sp);
|
|
stack.ss_size = current->sas_ss_size;
|
|
err |= __copy_to_user(&frame->uc.uc_stack, &stack, sizeof(stack));
|
|
|
|
err |= setup_sigcontext(&frame->uc.uc_mcontext, &frame->aux,
|
|
regs, set->sig[0]);
|
|
err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
|
|
|
|
if (err == 0)
|
|
err = setup_return(regs, ka, frame->retcode, frame, usig);
|
|
|
|
if (err == 0) {
|
|
/*
|
|
* For realtime signals we must also set the second and third
|
|
* arguments for the signal handler.
|
|
* -- Peter Maydell <pmaydell@chiark.greenend.org.uk> 2000-12-06
|
|
*/
|
|
regs->ARM_r1 = (unsigned long)&frame->info;
|
|
regs->ARM_r2 = (unsigned long)&frame->uc;
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static inline void restart_syscall(struct pt_regs *regs)
|
|
{
|
|
regs->ARM_r0 = regs->ARM_ORIG_r0;
|
|
regs->ARM_pc -= thumb_mode(regs) ? 2 : 4;
|
|
}
|
|
|
|
/*
|
|
* OK, we're invoking a handler
|
|
*/
|
|
static void
|
|
handle_signal(unsigned long sig, struct k_sigaction *ka,
|
|
siginfo_t *info, sigset_t *oldset,
|
|
struct pt_regs * regs, int syscall)
|
|
{
|
|
struct thread_info *thread = current_thread_info();
|
|
struct task_struct *tsk = current;
|
|
int usig = sig;
|
|
int ret;
|
|
|
|
/*
|
|
* If we were from a system call, check for system call restarting...
|
|
*/
|
|
if (syscall) {
|
|
switch (regs->ARM_r0) {
|
|
case -ERESTART_RESTARTBLOCK:
|
|
case -ERESTARTNOHAND:
|
|
regs->ARM_r0 = -EINTR;
|
|
break;
|
|
case -ERESTARTSYS:
|
|
if (!(ka->sa.sa_flags & SA_RESTART)) {
|
|
regs->ARM_r0 = -EINTR;
|
|
break;
|
|
}
|
|
/* fallthrough */
|
|
case -ERESTARTNOINTR:
|
|
restart_syscall(regs);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* translate the signal
|
|
*/
|
|
if (usig < 32 && thread->exec_domain && thread->exec_domain->signal_invmap)
|
|
usig = thread->exec_domain->signal_invmap[usig];
|
|
|
|
/*
|
|
* Set up the stack frame
|
|
*/
|
|
if (ka->sa.sa_flags & SA_SIGINFO)
|
|
ret = setup_rt_frame(usig, ka, info, oldset, regs);
|
|
else
|
|
ret = setup_frame(usig, ka, oldset, regs);
|
|
|
|
/*
|
|
* Check that the resulting registers are actually sane.
|
|
*/
|
|
ret |= !valid_user_regs(regs);
|
|
|
|
if (ret != 0) {
|
|
force_sigsegv(sig, tsk);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Block the signal if we were successful.
|
|
*/
|
|
spin_lock_irq(&tsk->sighand->siglock);
|
|
sigorsets(&tsk->blocked, &tsk->blocked,
|
|
&ka->sa.sa_mask);
|
|
if (!(ka->sa.sa_flags & SA_NODEFER))
|
|
sigaddset(&tsk->blocked, sig);
|
|
recalc_sigpending();
|
|
spin_unlock_irq(&tsk->sighand->siglock);
|
|
|
|
}
|
|
|
|
/*
|
|
* Note that 'init' is a special process: it doesn't get signals it doesn't
|
|
* want to handle. Thus you cannot kill init even with a SIGKILL even by
|
|
* mistake.
|
|
*
|
|
* Note that we go through the signals twice: once to check the signals that
|
|
* the kernel can handle, and then we build all the user-level signal handling
|
|
* stack-frames in one go after that.
|
|
*/
|
|
static int do_signal(sigset_t *oldset, struct pt_regs *regs, int syscall)
|
|
{
|
|
struct k_sigaction ka;
|
|
siginfo_t info;
|
|
int signr;
|
|
|
|
/*
|
|
* We want the common case to go fast, which
|
|
* is why we may in certain cases get here from
|
|
* kernel mode. Just return without doing anything
|
|
* if so.
|
|
*/
|
|
if (!user_mode(regs))
|
|
return 0;
|
|
|
|
if (try_to_freeze())
|
|
goto no_signal;
|
|
|
|
if (current->ptrace & PT_SINGLESTEP)
|
|
ptrace_cancel_bpt(current);
|
|
|
|
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
|
|
if (signr > 0) {
|
|
handle_signal(signr, &ka, &info, oldset, regs, syscall);
|
|
if (current->ptrace & PT_SINGLESTEP)
|
|
ptrace_set_bpt(current);
|
|
return 1;
|
|
}
|
|
|
|
no_signal:
|
|
/*
|
|
* No signal to deliver to the process - restart the syscall.
|
|
*/
|
|
if (syscall) {
|
|
if (regs->ARM_r0 == -ERESTART_RESTARTBLOCK) {
|
|
if (thumb_mode(regs)) {
|
|
regs->ARM_r7 = __NR_restart_syscall - __NR_SYSCALL_BASE;
|
|
regs->ARM_pc -= 2;
|
|
} else {
|
|
#if defined(CONFIG_AEABI) && !defined(CONFIG_OABI_COMPAT)
|
|
regs->ARM_r7 = __NR_restart_syscall;
|
|
regs->ARM_pc -= 4;
|
|
#else
|
|
u32 __user *usp;
|
|
u32 swival = __NR_restart_syscall;
|
|
|
|
regs->ARM_sp -= 12;
|
|
usp = (u32 __user *)regs->ARM_sp;
|
|
|
|
/*
|
|
* Either we supports OABI only, or we have
|
|
* EABI with the OABI compat layer enabled.
|
|
* In the later case we don't know if user
|
|
* space is EABI or not, and if not we must
|
|
* not clobber r7. Always using the OABI
|
|
* syscall solves that issue and works for
|
|
* all those cases.
|
|
*/
|
|
swival = swival - __NR_SYSCAll_BASE + __NR_OABI_SYSCALL_BASE;
|
|
|
|
put_user(regs->ARM_pc, &usp[0]);
|
|
/* swi __NR_restart_syscall */
|
|
put_user(0xef000000 | swival, &usp[1]);
|
|
/* ldr pc, [sp], #12 */
|
|
put_user(0xe49df00c, &usp[2]);
|
|
|
|
flush_icache_range((unsigned long)usp,
|
|
(unsigned long)(usp + 3));
|
|
|
|
regs->ARM_pc = regs->ARM_sp + 4;
|
|
#endif
|
|
}
|
|
}
|
|
if (regs->ARM_r0 == -ERESTARTNOHAND ||
|
|
regs->ARM_r0 == -ERESTARTSYS ||
|
|
regs->ARM_r0 == -ERESTARTNOINTR) {
|
|
restart_syscall(regs);
|
|
}
|
|
}
|
|
if (current->ptrace & PT_SINGLESTEP)
|
|
ptrace_set_bpt(current);
|
|
return 0;
|
|
}
|
|
|
|
asmlinkage void
|
|
do_notify_resume(struct pt_regs *regs, unsigned int thread_flags, int syscall)
|
|
{
|
|
if (thread_flags & _TIF_SIGPENDING)
|
|
do_signal(¤t->blocked, regs, syscall);
|
|
}
|