Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 748 insertions, 0 deletions

diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
new file mode 100644
index 000000000000..931919fd5121
--- /dev/null
+++ b/arch/arm/kernel/signal.c
@@ -0,0 +1,748 @@
+/*
+ *  linux/arch/arm/kernel/signal.c
+ *
+ *  Copyright (C) 1995-2002 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/ptrace.h>
+#include <linux/personality.h>
+
+#include <asm/cacheflush.h>
+#include <asm/ucontext.h>
+#include <asm/uaccess.h>
+#include <asm/unistd.h>
+
+#include "ptrace.h"
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+/*
+ * For ARM syscalls, we encode the syscall number into the instruction.
+ */
+#define SWI_SYS_SIGRETURN	(0xef000000|(__NR_sigreturn))
+#define SWI_SYS_RT_SIGRETURN	(0xef000000|(__NR_rt_sigreturn))
+
+/*
+ * For Thumb syscalls, we pass the syscall number via r7.  We therefore
+ * need two 16-bit instructions.
+ */
+#define SWI_THUMB_SIGRETURN	(0xdf00 << 16 | 0x2700 | (__NR_sigreturn - __NR_SYSCALL_BASE))
+#define SWI_THUMB_RT_SIGRETURN	(0xdf00 << 16 | 0x2700 | (__NR_rt_sigreturn - __NR_SYSCALL_BASE))
+
+static const unsigned long retcodes[4] = {
+	SWI_SYS_SIGRETURN,	SWI_THUMB_SIGRETURN,
+	SWI_SYS_RT_SIGRETURN,	SWI_THUMB_RT_SIGRETURN
+};
+
+static int do_signal(sigset_t *oldset, struct pt_regs * regs, int syscall);
+
+/*
+ * atomically swap in the new signal mask, and wait for a signal.
+ */
+asmlinkage int sys_sigsuspend(int restart, unsigned long oldmask, old_sigset_t mask, struct pt_regs *regs)
+{
+	sigset_t saveset;
+
+	mask &= _BLOCKABLE;
+	spin_lock_irq(&current->sighand->siglock);
+	saveset = current->blocked;
+	siginitset(&current->blocked, mask);
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
+	regs->ARM_r0 = -EINTR;
+
+	while (1) {
+		current->state = TASK_INTERRUPTIBLE;
+		schedule();
+		if (do_signal(&saveset, regs, 0))
+			return regs->ARM_r0;
+	}
+}
+
+asmlinkage int
+sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize, struct pt_regs *regs)
+{
+	sigset_t saveset, newset;
+
+	/* XXX: Don't preclude handling different sized sigset_t's. */
+	if (sigsetsize != sizeof(sigset_t))
+		return -EINVAL;
+
+	if (copy_from_user(&newset, unewset, sizeof(newset)))
+		return -EFAULT;
+	sigdelsetmask(&newset, ~_BLOCKABLE);
+
+	spin_lock_irq(&current->sighand->siglock);
+	saveset = current->blocked;
+	current->blocked = newset;
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
+	regs->ARM_r0 = -EINTR;
+
+	while (1) {
+		current->state = TASK_INTERRUPTIBLE;
+		schedule();
+		if (do_signal(&saveset, regs, 0))
+			return regs->ARM_r0;
+	}
+}
+
+asmlinkage int 
+sys_sigaction(int sig, const struct old_sigaction __user *act,
+	      struct old_sigaction __user *oact)
+{
+	struct k_sigaction new_ka, old_ka;
+	int ret;
+
+	if (act) {
+		old_sigset_t mask;
+		if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
+		    __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
+		    __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
+			return -EFAULT;
+		__get_user(new_ka.sa.sa_flags, &act->sa_flags);
+		__get_user(mask, &act->sa_mask);
+		siginitset(&new_ka.sa.sa_mask, mask);
+	}
+
+	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
+
+	if (!ret && oact) {
+		if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
+		    __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
+		    __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
+			return -EFAULT;
+		__put_user(old_ka.sa.sa_flags, &oact->sa_flags);
+		__put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
+	}
+
+	return ret;
+}
+
+#ifdef CONFIG_IWMMXT
+
+/* iwmmxt_area is 0x98 bytes long, preceeded by 8 bytes of signature */
+#define IWMMXT_STORAGE_SIZE	(0x98 + 8)
+#define IWMMXT_MAGIC0		0x12ef842a
+#define IWMMXT_MAGIC1		0x1c07ca71
+
+struct iwmmxt_sigframe {
+	unsigned long	magic0;
+	unsigned long	magic1;
+	unsigned long	storage[0x98/4];
+};
+
+static int page_present(struct mm_struct *mm, void __user *uptr, int wr)
+{
+	unsigned long addr = (unsigned long)uptr;
+	pgd_t *pgd = pgd_offset(mm, addr);
+	if (pgd_present(*pgd)) {
+		pmd_t *pmd = pmd_offset(pgd, addr);
+		if (pmd_present(*pmd)) {
+			pte_t *pte = pte_offset_map(pmd, addr);
+			return (pte_present(*pte) && (!wr || pte_write(*pte)));
+		}
+	}
+	return 0;
+}
+
+static int copy_locked(void __user *uptr, void *kptr, size_t size, int write,
+		       void (*copyfn)(void *, void __user *))
+{
+	unsigned char v, __user *userptr = uptr;
+	int err = 0;
+
+	do {
+		struct mm_struct *mm;
+
+		if (write) {
+			__put_user_error(0, userptr, err);
+			__put_user_error(0, userptr + size - 1, err);
+		} else {
+			__get_user_error(v, userptr, err);
+			__get_user_error(v, userptr + size - 1, err);
+		}
+
+		if (err)
+			break;
+
+		mm = current->mm;
+		spin_lock(&mm->page_table_lock);
+		if (page_present(mm, userptr, write) &&
+		    page_present(mm, userptr + size - 1, write)) {
+		    	copyfn(kptr, uptr);
+		} else
+			err = 1;
+		spin_unlock(&mm->page_table_lock);
+	} while (err);
+
+	return err;
+}
+
+static int preserve_iwmmxt_context(struct iwmmxt_sigframe *frame)
+{
+	int err = 0;
+
+	/* the iWMMXt context must be 64 bit aligned */
+	WARN_ON((unsigned long)frame & 7);
+
+	__put_user_error(IWMMXT_MAGIC0, &frame->magic0, err);
+	__put_user_error(IWMMXT_MAGIC1, &frame->magic1, err);
+
+	/*
+	 * iwmmxt_task_copy() doesn't check user permissions.
+	 * Let's do a dummy write on the upper boundary to ensure
+	 * access to user mem is OK all way up.
+	 */
+	err |= copy_locked(&frame->storage, current_thread_info(),
+			   sizeof(frame->storage), 1, iwmmxt_task_copy);
+	return err;
+}
+
+static int restore_iwmmxt_context(struct iwmmxt_sigframe *frame)
+{
+	unsigned long magic0, magic1;
+	int err = 0;
+
+	/* the iWMMXt context is 64 bit aligned */
+	WARN_ON((unsigned long)frame & 7);
+
+	/*
+	 * Validate iWMMXt context signature.
+	 * Also, iwmmxt_task_restore() doesn't check user permissions.
+	 * Let's do a dummy write on the upper boundary to ensure
+	 * access to user mem is OK all way up.
+	 */
+	__get_user_error(magic0, &frame->magic0, err);
+	__get_user_error(magic1, &frame->magic1, err);
+	if (!err && magic0 == IWMMXT_MAGIC0 && magic1 == IWMMXT_MAGIC1)
+		err = copy_locked(&frame->storage, current_thread_info(),
+				  sizeof(frame->storage), 0, iwmmxt_task_restore);
+	return err;
+}
+
+#endif
+
+/*
+ * Auxiliary signal frame.  This saves stuff like FP state.
+ * The layout of this structure is not part of the user ABI.
+ */
+struct aux_sigframe {
+#ifdef CONFIG_IWMMXT
+	struct iwmmxt_sigframe	iwmmxt;
+#endif
+#ifdef CONFIG_VFP
+	union vfp_state		vfp;
+#endif
+};
+
+/*
+ * Do a signal return; undo the signal stack.  These are aligned to 64-bit.
+ */
+struct sigframe {
+	struct sigcontext sc;
+	unsigned long extramask[_NSIG_WORDS-1];
+	unsigned long retcode;
+	struct aux_sigframe aux __attribute__((aligned(8)));
+};
+
+struct rt_sigframe {
+	struct siginfo __user *pinfo;
+	void __user *puc;
+	struct siginfo info;
+	struct ucontext uc;
+	unsigned long retcode;
+	struct aux_sigframe aux __attribute__((aligned(8)));
+};
+
+static int
+restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
+		   struct aux_sigframe __user *aux)
+{
+	int err = 0;
+
+	__get_user_error(regs->ARM_r0, &sc->arm_r0, err);
+	__get_user_error(regs->ARM_r1, &sc->arm_r1, err);
+	__get_user_error(regs->ARM_r2, &sc->arm_r2, err);
+	__get_user_error(regs->ARM_r3, &sc->arm_r3, err);
+	__get_user_error(regs->ARM_r4, &sc->arm_r4, err);
+	__get_user_error(regs->ARM_r5, &sc->arm_r5, err);
+	__get_user_error(regs->ARM_r6, &sc->arm_r6, err);
+	__get_user_error(regs->ARM_r7, &sc->arm_r7, err);
+	__get_user_error(regs->ARM_r8, &sc->arm_r8, err);
+	__get_user_error(regs->ARM_r9, &sc->arm_r9, err);
+	__get_user_error(regs->ARM_r10, &sc->arm_r10, err);
+	__get_user_error(regs->ARM_fp, &sc->arm_fp, err);
+	__get_user_error(regs->ARM_ip, &sc->arm_ip, err);
+	__get_user_error(regs->ARM_sp, &sc->arm_sp, err);
+	__get_user_error(regs->ARM_lr, &sc->arm_lr, err);
+	__get_user_error(regs->ARM_pc, &sc->arm_pc, err);
+	__get_user_error(regs->ARM_cpsr, &sc->arm_cpsr, err);
+
+	err |= !valid_user_regs(regs);
+
+#ifdef CONFIG_IWMMXT
+	if (err == 0 && test_thread_flag(TIF_USING_IWMMXT))
+		err |= restore_iwmmxt_context(&aux->iwmmxt);
+#endif
+#ifdef CONFIG_VFP
+//	if (err == 0)
+//		err |= vfp_restore_state(&aux->vfp);
+#endif
+
+	return err;
+}
+
+asmlinkage int sys_sigreturn(struct pt_regs *regs)
+{
+	struct sigframe __user *frame;
+	sigset_t set;
+
+	/* Always make any pending restarted system calls return -EINTR */
+	current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
+	/*
+	 * Since we stacked the signal on a 64-bit boundary,
+	 * then 'sp' should be word aligned here.  If it's
+	 * not, then the user is trying to mess with us.
+	 */
+	if (regs->ARM_sp & 7)
+		goto badframe;
+
+	frame = (struct sigframe __user *)regs->ARM_sp;
+
+	if (!access_ok(VERIFY_READ, frame, sizeof (*frame)))
+		goto badframe;
+	if (__get_user(set.sig[0], &frame->sc.oldmask)
+	    || (_NSIG_WORDS > 1
+	        && __copy_from_user(&set.sig[1], &frame->extramask,
+				    sizeof(frame->extramask))))
+		goto badframe;
+
+	sigdelsetmask(&set, ~_BLOCKABLE);
+	spin_lock_irq(&current->sighand->siglock);
+	current->blocked = set;
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
+
+	if (restore_sigcontext(regs, &frame->sc, &frame->aux))
+		goto badframe;
+
+	/* Send SIGTRAP if we're single-stepping */
+	if (current->ptrace & PT_SINGLESTEP) {
+		ptrace_cancel_bpt(current);
+		send_sig(SIGTRAP, current, 1);
+	}
+
+	return regs->ARM_r0;
+
+badframe:
+	force_sig(SIGSEGV, current);
+	return 0;
+}
+
+asmlinkage int sys_rt_sigreturn(struct pt_regs *regs)
+{
+	struct rt_sigframe __user *frame;
+	sigset_t set;
+
+	/* Always make any pending restarted system calls return -EINTR */
+	current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
+	/*
+	 * Since we stacked the signal on a 64-bit boundary,
+	 * then 'sp' should be word aligned here.  If it's
+	 * not, then the user is trying to mess with us.
+	 */
+	if (regs->ARM_sp & 7)
+		goto badframe;
+
+	frame = (struct rt_sigframe __user *)regs->ARM_sp;
+
+	if (!access_ok(VERIFY_READ, frame, sizeof (*frame)))
+		goto badframe;
+	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
+		goto badframe;
+
+	sigdelsetmask(&set, ~_BLOCKABLE);
+	spin_lock_irq(&current->sighand->siglock);
+	current->blocked = set;
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
+
+	if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &frame->aux))
+		goto badframe;
+
+	if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->ARM_sp) == -EFAULT)
+		goto badframe;
+
+	/* Send SIGTRAP if we're single-stepping */
+	if (current->ptrace & PT_SINGLESTEP) {
+		ptrace_cancel_bpt(current);
+		send_sig(SIGTRAP, current, 1);
+	}
+
+	return regs->ARM_r0;
+
+badframe:
+	force_sig(SIGSEGV, current);
+	return 0;
+}
+
+static int
+setup_sigcontext(struct sigcontext __user *sc, struct aux_sigframe __user *aux,
+		 struct pt_regs *regs, unsigned long mask)
+{
+	int err = 0;
+
+	__put_user_error(regs->ARM_r0, &sc->arm_r0, err);
+	__put_user_error(regs->ARM_r1, &sc->arm_r1, err);
+	__put_user_error(regs->ARM_r2, &sc->arm_r2, err);
+	__put_user_error(regs->ARM_r3, &sc->arm_r3, err);
+	__put_user_error(regs->ARM_r4, &sc->arm_r4, err);
+	__put_user_error(regs->ARM_r5, &sc->arm_r5, err);
+	__put_user_error(regs->ARM_r6, &sc->arm_r6, err);
+	__put_user_error(regs->ARM_r7, &sc->arm_r7, err);
+	__put_user_error(regs->ARM_r8, &sc->arm_r8, err);
+	__put_user_error(regs->ARM_r9, &sc->arm_r9, err);
+	__put_user_error(regs->ARM_r10, &sc->arm_r10, err);
+	__put_user_error(regs->ARM_fp, &sc->arm_fp, err);
+	__put_user_error(regs->ARM_ip, &sc->arm_ip, err);
+	__put_user_error(regs->ARM_sp, &sc->arm_sp, err);
+	__put_user_error(regs->ARM_lr, &sc->arm_lr, err);
+	__put_user_error(regs->ARM_pc, &sc->arm_pc, err);
+	__put_user_error(regs->ARM_cpsr, &sc->arm_cpsr, err);
+
+	__put_user_error(current->thread.trap_no, &sc->trap_no, err);
+	__put_user_error(current->thread.error_code, &sc->error_code, err);
+	__put_user_error(current->thread.address, &sc->fault_address, err);
+	__put_user_error(mask, &sc->oldmask, err);
+
+#ifdef CONFIG_IWMMXT
+	if (err == 0 && test_thread_flag(TIF_USING_IWMMXT))
+		err |= preserve_iwmmxt_context(&aux->iwmmxt);
+#endif
+#ifdef CONFIG_VFP
+//	if (err == 0)
+//		err |= vfp_save_state(&aux->vfp);
+#endif
+
+	return err;
+}
+
+static inline void __user *
+get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, int framesize)
+{
+	unsigned long sp = regs->ARM_sp;
+	void __user *frame;
+
+	/*
+	 * This is the X/Open sanctioned signal stack switching.
+	 */
+	if ((ka->sa.sa_flags & SA_ONSTACK) && !sas_ss_flags(sp))
+		sp = current->sas_ss_sp + current->sas_ss_size;
+
+	/*
+	 * ATPCS B01 mandates 8-byte alignment
+	 */
+	frame = (void __user *)((sp - framesize) & ~7);
+
+	/*
+	 * Check that we can actually write to the signal frame.
+	 */
+	if (!access_ok(VERIFY_WRITE, frame, framesize))
+		frame = NULL;
+
+	return frame;
+}
+
+static int
+setup_return(struct pt_regs *regs, struct k_sigaction *ka,
+	     unsigned long __user *rc, void __user *frame, int usig)
+{
+	unsigned long handler = (unsigned long)ka->sa.sa_handler;
+	unsigned long retcode;
+	int thumb = 0;
+	unsigned long cpsr = regs->ARM_cpsr & ~PSR_f;
+
+	/*
+	 * Maybe we need to deliver a 32-bit signal to a 26-bit task.
+	 */
+	if (ka->sa.sa_flags & SA_THIRTYTWO)
+		cpsr = (cpsr & ~MODE_MASK) | USR_MODE;
+
+#ifdef CONFIG_ARM_THUMB
+	if (elf_hwcap & HWCAP_THUMB) {
+		/*
+		 * The LSB of the handler determines if we're going to
+		 * be using THUMB or ARM mode for this signal handler.
+		 */
+		thumb = handler & 1;
+
+		if (thumb)
+			cpsr |= PSR_T_BIT;
+		else
+			cpsr &= ~PSR_T_BIT;
+	}
+#endif
+
+	if (ka->sa.sa_flags & SA_RESTORER) {
+		retcode = (unsigned long)ka->sa.sa_restorer;
+	} else {
+		unsigned int idx = thumb;
+
+		if (ka->sa.sa_flags & SA_SIGINFO)
+			idx += 2;
+
+		if (__put_user(retcodes[idx], rc))
+			return 1;
+
+		/*
+		 * Ensure that the instruction cache sees
+		 * the return code written onto the stack.
+		 */
+		flush_icache_range((unsigned long)rc,
+				   (unsigned long)(rc + 1));
+
+		retcode = ((unsigned long)rc) + thumb;
+	}
+
+	regs->ARM_r0 = usig;
+	regs->ARM_sp = (unsigned long)frame;
+	regs->ARM_lr = retcode;
+	regs->ARM_pc = handler;
+	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);
+
+	/*
+	 * Block the signal if we were unsuccessful.
+	 */
+	if (ret != 0 || !(ka->sa.sa_flags & SA_NODEFER)) {
+		spin_lock_irq(&tsk->sighand->siglock);
+		sigorsets(&tsk->blocked, &tsk->blocked,
+			  &ka->sa.sa_mask);
+		sigaddset(&tsk->blocked, sig);
+		recalc_sigpending();
+		spin_unlock_irq(&tsk->sighand->siglock);
+	}
+
+	if (ret == 0)
+		return;
+
+	force_sigsegv(sig, tsk);
+}
+
+/*
+ * 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(0))
+		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;
+				regs->ARM_pc -= 2;
+			} else {
+				u32 __user *usp;
+
+				regs->ARM_sp -= 12;
+				usp = (u32 __user *)regs->ARM_sp;
+
+				put_user(regs->ARM_pc, &usp[0]);
+				/* swi __NR_restart_syscall */
+				put_user(0xef000000 | __NR_restart_syscall, &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;
+			}
+		}
+		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(&current->blocked, regs, syscall);
+}