i386: move kernel

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 667 insertions, 0 deletions

diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c
new file mode 100644
index 0000000..c03570f
--- /dev/null
+++ b/arch/x86/kernel/signal_32.c
@@ -0,0 +1,667 @@
+/*
+ *  linux/arch/i386/kernel/signal.c
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ *
+ *  1997-11-28  Modified for POSIX.1b signals by Richard Henderson
+ *  2000-06-20  Pentium III FXSR, SSE support by Gareth Hughes
+ */
+
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/errno.h>
+#include <linux/wait.h>
+#include <linux/unistd.h>
+#include <linux/stddef.h>
+#include <linux/personality.h>
+#include <linux/suspend.h>
+#include <linux/ptrace.h>
+#include <linux/elf.h>
+#include <linux/binfmts.h>
+#include <asm/processor.h>
+#include <asm/ucontext.h>
+#include <asm/uaccess.h>
+#include <asm/i387.h>
+#include "sigframe_32.h"
+
+#define DEBUG_SIG 0
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+/*
+ * Atomically swap in the new signal mask, and wait for a signal.
+ */
+asmlinkage int
+sys_sigsuspend(int history0, int history1, old_sigset_t mask)
+{
+	mask &= _BLOCKABLE;
+	spin_lock_irq(&current->sighand->siglock);
+	current->saved_sigmask = current->blocked;
+	siginitset(&current->blocked, mask);
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
+
+	current->state = TASK_INTERRUPTIBLE;
+	schedule();
+	set_thread_flag(TIF_RESTORE_SIGMASK);
+	return -ERESTARTNOHAND;
+}
+
+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;
+}
+
+asmlinkage int
+sys_sigaltstack(unsigned long ebx)
+{
+	/* This is needed to make gcc realize it doesn't own the "struct pt_regs" */
+	struct pt_regs *regs = (struct pt_regs *)&ebx;
+	const stack_t __user *uss = (const stack_t __user *)ebx;
+	stack_t __user *uoss = (stack_t __user *)regs->ecx;
+
+	return do_sigaltstack(uss, uoss, regs->esp);
+}
+
+
+/*
+ * Do a signal return; undo the signal stack.
+ */
+
+static int
+restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *peax)
+{
+	unsigned int err = 0;
+
+	/* Always make any pending restarted system calls return -EINTR */
+	current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
+#define COPY(x)		err |= __get_user(regs->x, &sc->x)
+
+#define COPY_SEG(seg)							\
+	{ unsigned short tmp;						\
+	  err |= __get_user(tmp, &sc->seg);				\
+	  regs->x##seg = tmp; }
+
+#define COPY_SEG_STRICT(seg)						\
+	{ unsigned short tmp;						\
+	  err |= __get_user(tmp, &sc->seg);				\
+	  regs->x##seg = tmp|3; }
+
+#define GET_SEG(seg)							\
+	{ unsigned short tmp;						\
+	  err |= __get_user(tmp, &sc->seg);				\
+	  loadsegment(seg,tmp); }
+
+#define	FIX_EFLAGS	(X86_EFLAGS_AC | X86_EFLAGS_RF |		 \
+			 X86_EFLAGS_OF | X86_EFLAGS_DF |		 \
+			 X86_EFLAGS_TF | X86_EFLAGS_SF | X86_EFLAGS_ZF | \
+			 X86_EFLAGS_AF | X86_EFLAGS_PF | X86_EFLAGS_CF)
+
+	GET_SEG(gs);
+	COPY_SEG(fs);
+	COPY_SEG(es);
+	COPY_SEG(ds);
+	COPY(edi);
+	COPY(esi);
+	COPY(ebp);
+	COPY(esp);
+	COPY(ebx);
+	COPY(edx);
+	COPY(ecx);
+	COPY(eip);
+	COPY_SEG_STRICT(cs);
+	COPY_SEG_STRICT(ss);
+	
+	{
+		unsigned int tmpflags;
+		err |= __get_user(tmpflags, &sc->eflags);
+		regs->eflags = (regs->eflags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
+		regs->orig_eax = -1;		/* disable syscall checks */
+	}
+
+	{
+		struct _fpstate __user * buf;
+		err |= __get_user(buf, &sc->fpstate);
+		if (buf) {
+			if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
+				goto badframe;
+			err |= restore_i387(buf);
+		} else {
+			struct task_struct *me = current;
+			if (used_math()) {
+				clear_fpu(me);
+				clear_used_math();
+			}
+		}
+	}
+
+	err |= __get_user(*peax, &sc->eax);
+	return err;
+
+badframe:
+	return 1;
+}
+
+asmlinkage int sys_sigreturn(unsigned long __unused)
+{
+	struct pt_regs *regs = (struct pt_regs *) &__unused;
+	struct sigframe __user *frame = (struct sigframe __user *)(regs->esp - 8);
+	sigset_t set;
+	int eax;
+
+	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, &eax))
+		goto badframe;
+	return eax;
+
+badframe:
+	if (show_unhandled_signals && printk_ratelimit())
+		printk("%s%s[%d] bad frame in sigreturn frame:%p eip:%lx"
+		       " esp:%lx oeax:%lx\n",
+		    current->pid > 1 ? KERN_INFO : KERN_EMERG,
+		    current->comm, current->pid, frame, regs->eip,
+		    regs->esp, regs->orig_eax);
+
+	force_sig(SIGSEGV, current);
+	return 0;
+}	
+
+asmlinkage int sys_rt_sigreturn(unsigned long __unused)
+{
+	struct pt_regs *regs = (struct pt_regs *) &__unused;
+	struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(regs->esp - 4);
+	sigset_t set;
+	int eax;
+
+	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, &eax))
+		goto badframe;
+
+	if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->esp) == -EFAULT)
+		goto badframe;
+
+	return eax;
+
+badframe:
+	force_sig(SIGSEGV, current);
+	return 0;
+}	
+
+/*
+ * Set up a signal frame.
+ */
+
+static int
+setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate,
+		 struct pt_regs *regs, unsigned long mask)
+{
+	int tmp, err = 0;
+
+	err |= __put_user(regs->xfs, (unsigned int __user *)&sc->fs);
+	savesegment(gs, tmp);
+	err |= __put_user(tmp, (unsigned int __user *)&sc->gs);
+
+	err |= __put_user(regs->xes, (unsigned int __user *)&sc->es);
+	err |= __put_user(regs->xds, (unsigned int __user *)&sc->ds);
+	err |= __put_user(regs->edi, &sc->edi);
+	err |= __put_user(regs->esi, &sc->esi);
+	err |= __put_user(regs->ebp, &sc->ebp);
+	err |= __put_user(regs->esp, &sc->esp);
+	err |= __put_user(regs->ebx, &sc->ebx);
+	err |= __put_user(regs->edx, &sc->edx);
+	err |= __put_user(regs->ecx, &sc->ecx);
+	err |= __put_user(regs->eax, &sc->eax);
+	err |= __put_user(current->thread.trap_no, &sc->trapno);
+	err |= __put_user(current->thread.error_code, &sc->err);
+	err |= __put_user(regs->eip, &sc->eip);
+	err |= __put_user(regs->xcs, (unsigned int __user *)&sc->cs);
+	err |= __put_user(regs->eflags, &sc->eflags);
+	err |= __put_user(regs->esp, &sc->esp_at_signal);
+	err |= __put_user(regs->xss, (unsigned int __user *)&sc->ss);
+
+	tmp = save_i387(fpstate);
+	if (tmp < 0)
+	  err = 1;
+	else
+	  err |= __put_user(tmp ? fpstate : NULL, &sc->fpstate);
+
+	/* non-iBCS2 extensions.. */
+	err |= __put_user(mask, &sc->oldmask);
+	err |= __put_user(current->thread.cr2, &sc->cr2);
+
+	return err;
+}
+
+/*
+ * Determine which stack to use..
+ */
+static inline void __user *
+get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
+{
+	unsigned long esp;
+
+	/* Default to using normal stack */
+	esp = regs->esp;
+
+	/* This is the X/Open sanctioned signal stack switching.  */
+	if (ka->sa.sa_flags & SA_ONSTACK) {
+		if (sas_ss_flags(esp) == 0)
+			esp = current->sas_ss_sp + current->sas_ss_size;
+	}
+
+	/* This is the legacy signal stack switching. */
+	else if ((regs->xss & 0xffff) != __USER_DS &&
+		 !(ka->sa.sa_flags & SA_RESTORER) &&
+		 ka->sa.sa_restorer) {
+		esp = (unsigned long) ka->sa.sa_restorer;
+	}
+
+	esp -= frame_size;
+	/* Align the stack pointer according to the i386 ABI,
+	 * i.e. so that on function entry ((sp + 4) & 15) == 0. */
+	esp = ((esp + 4) & -16ul) - 4;
+	return (void __user *) esp;
+}
+
+/* These symbols are defined with the addresses in the vsyscall page.
+   See vsyscall-sigreturn.S.  */
+extern void __user __kernel_sigreturn;
+extern void __user __kernel_rt_sigreturn;
+
+static int setup_frame(int sig, struct k_sigaction *ka,
+		       sigset_t *set, struct pt_regs * regs)
+{
+	void __user *restorer;
+	struct sigframe __user *frame;
+	int err = 0;
+	int usig;
+
+	frame = get_sigframe(ka, regs, sizeof(*frame));
+
+	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+		goto give_sigsegv;
+
+	usig = current_thread_info()->exec_domain
+		&& current_thread_info()->exec_domain->signal_invmap
+		&& sig < 32
+		? current_thread_info()->exec_domain->signal_invmap[sig]
+		: sig;
+
+	err = __put_user(usig, &frame->sig);
+	if (err)
+		goto give_sigsegv;
+
+	err = setup_sigcontext(&frame->sc, &frame->fpstate, regs, set->sig[0]);
+	if (err)
+		goto give_sigsegv;
+
+	if (_NSIG_WORDS > 1) {
+		err = __copy_to_user(&frame->extramask, &set->sig[1],
+				      sizeof(frame->extramask));
+		if (err)
+			goto give_sigsegv;
+	}
+
+	if (current->binfmt->hasvdso)
+		restorer = (void *)VDSO_SYM(&__kernel_sigreturn);
+	else
+		restorer = (void *)&frame->retcode;
+	if (ka->sa.sa_flags & SA_RESTORER)
+		restorer = ka->sa.sa_restorer;
+
+	/* Set up to return from userspace.  */
+	err |= __put_user(restorer, &frame->pretcode);
+	 
+	/*
+	 * This is popl %eax ; movl $,%eax ; int $0x80
+	 *
+	 * WE DO NOT USE IT ANY MORE! It's only left here for historical
+	 * reasons and because gdb uses it as a signature to notice
+	 * signal handler stack frames.
+	 */
+	err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
+	err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
+	err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));
+
+	if (err)
+		goto give_sigsegv;
+
+	/* Set up registers for signal handler */
+	regs->esp = (unsigned long) frame;
+	regs->eip = (unsigned long) ka->sa.sa_handler;
+	regs->eax = (unsigned long) sig;
+	regs->edx = (unsigned long) 0;
+	regs->ecx = (unsigned long) 0;
+
+	set_fs(USER_DS);
+	regs->xds = __USER_DS;
+	regs->xes = __USER_DS;
+	regs->xss = __USER_DS;
+	regs->xcs = __USER_CS;
+
+	/*
+	 * Clear TF when entering the signal handler, but
+	 * notify any tracer that was single-stepping it.
+	 * The tracer may want to single-step inside the
+	 * handler too.
+	 */
+	regs->eflags &= ~TF_MASK;
+	if (test_thread_flag(TIF_SINGLESTEP))
+		ptrace_notify(SIGTRAP);
+
+#if DEBUG_SIG
+	printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
+		current->comm, current->pid, frame, regs->eip, frame->pretcode);
+#endif
+
+	return 0;
+
+give_sigsegv:
+	force_sigsegv(sig, current);
+	return -EFAULT;
+}
+
+static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+			   sigset_t *set, struct pt_regs * regs)
+{
+	void __user *restorer;
+	struct rt_sigframe __user *frame;
+	int err = 0;
+	int usig;
+
+	frame = get_sigframe(ka, regs, sizeof(*frame));
+
+	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+		goto give_sigsegv;
+
+	usig = current_thread_info()->exec_domain
+		&& current_thread_info()->exec_domain->signal_invmap
+		&& sig < 32
+		? current_thread_info()->exec_domain->signal_invmap[sig]
+		: sig;
+
+	err |= __put_user(usig, &frame->sig);
+	err |= __put_user(&frame->info, &frame->pinfo);
+	err |= __put_user(&frame->uc, &frame->puc);
+	err |= copy_siginfo_to_user(&frame->info, info);
+	if (err)
+		goto give_sigsegv;
+
+	/* Create the ucontext.  */
+	err |= __put_user(0, &frame->uc.uc_flags);
+	err |= __put_user(0, &frame->uc.uc_link);
+	err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
+	err |= __put_user(sas_ss_flags(regs->esp),
+			  &frame->uc.uc_stack.ss_flags);
+	err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
+	err |= setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate,
+			        regs, set->sig[0]);
+	err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+	if (err)
+		goto give_sigsegv;
+
+	/* Set up to return from userspace.  */
+	restorer = (void *)VDSO_SYM(&__kernel_rt_sigreturn);
+	if (ka->sa.sa_flags & SA_RESTORER)
+		restorer = ka->sa.sa_restorer;
+	err |= __put_user(restorer, &frame->pretcode);
+	 
+	/*
+	 * This is movl $,%eax ; int $0x80
+	 *
+	 * WE DO NOT USE IT ANY MORE! It's only left here for historical
+	 * reasons and because gdb uses it as a signature to notice
+	 * signal handler stack frames.
+	 */
+	err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
+	err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
+	err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));
+
+	if (err)
+		goto give_sigsegv;
+
+	/* Set up registers for signal handler */
+	regs->esp = (unsigned long) frame;
+	regs->eip = (unsigned long) ka->sa.sa_handler;
+	regs->eax = (unsigned long) usig;
+	regs->edx = (unsigned long) &frame->info;
+	regs->ecx = (unsigned long) &frame->uc;
+
+	set_fs(USER_DS);
+	regs->xds = __USER_DS;
+	regs->xes = __USER_DS;
+	regs->xss = __USER_DS;
+	regs->xcs = __USER_CS;
+
+	/*
+	 * Clear TF when entering the signal handler, but
+	 * notify any tracer that was single-stepping it.
+	 * The tracer may want to single-step inside the
+	 * handler too.
+	 */
+	regs->eflags &= ~TF_MASK;
+	if (test_thread_flag(TIF_SINGLESTEP))
+		ptrace_notify(SIGTRAP);
+
+#if DEBUG_SIG
+	printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
+		current->comm, current->pid, frame, regs->eip, frame->pretcode);
+#endif
+
+	return 0;
+
+give_sigsegv:
+	force_sigsegv(sig, current);
+	return -EFAULT;
+}
+
+/*
+ * OK, we're invoking a handler
+ */	
+
+static int
+handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
+	      sigset_t *oldset,	struct pt_regs * regs)
+{
+	int ret;
+
+	/* Are we from a system call? */
+	if (regs->orig_eax >= 0) {
+		/* If so, check system call restarting.. */
+		switch (regs->eax) {
+		        case -ERESTART_RESTARTBLOCK:
+			case -ERESTARTNOHAND:
+				regs->eax = -EINTR;
+				break;
+
+			case -ERESTARTSYS:
+				if (!(ka->sa.sa_flags & SA_RESTART)) {
+					regs->eax = -EINTR;
+					break;
+				}
+			/* fallthrough */
+			case -ERESTARTNOINTR:
+				regs->eax = regs->orig_eax;
+				regs->eip -= 2;
+		}
+	}
+
+	/*
+	 * If TF is set due to a debugger (PT_DTRACE), clear the TF flag so
+	 * that register information in the sigcontext is correct.
+	 */
+	if (unlikely(regs->eflags & TF_MASK)
+	    && likely(current->ptrace & PT_DTRACE)) {
+		current->ptrace &= ~PT_DTRACE;
+		regs->eflags &= ~TF_MASK;
+	}
+
+	/* Set up the stack frame */
+	if (ka->sa.sa_flags & SA_SIGINFO)
+		ret = setup_rt_frame(sig, ka, info, oldset, regs);
+	else
+		ret = setup_frame(sig, ka, oldset, regs);
+
+	if (ret == 0) {
+		spin_lock_irq(&current->sighand->siglock);
+		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+		if (!(ka->sa.sa_flags & SA_NODEFER))
+			sigaddset(&current->blocked,sig);
+		recalc_sigpending();
+		spin_unlock_irq(&current->sighand->siglock);
+	}
+
+	return ret;
+}
+
+/*
+ * 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.
+ */
+static void fastcall do_signal(struct pt_regs *regs)
+{
+	siginfo_t info;
+	int signr;
+	struct k_sigaction ka;
+	sigset_t *oldset;
+
+	/*
+	 * 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.  vm86 regs switched out by assembly code
+ 	 * before reaching here, so testing against kernel
+ 	 * CS suffices.
+	 */
+	if (!user_mode(regs))
+		return;
+
+	if (test_thread_flag(TIF_RESTORE_SIGMASK))
+		oldset = &current->saved_sigmask;
+	else
+		oldset = &current->blocked;
+
+	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
+	if (signr > 0) {
+		/* Reenable any watchpoints before delivering the
+		 * signal to user space. The processor register will
+		 * have been cleared if the watchpoint triggered
+		 * inside the kernel.
+		 */
+		if (unlikely(current->thread.debugreg[7]))
+			set_debugreg(current->thread.debugreg[7], 7);
+
+		/* Whee!  Actually deliver the signal.  */
+		if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
+			/* a signal was successfully delivered; the saved
+			 * sigmask will have been stored in the signal frame,
+			 * and will be restored by sigreturn, so we can simply
+			 * clear the TIF_RESTORE_SIGMASK flag */
+			if (test_thread_flag(TIF_RESTORE_SIGMASK))
+				clear_thread_flag(TIF_RESTORE_SIGMASK);
+		}
+
+		return;
+	}
+
+	/* Did we come from a system call? */
+	if (regs->orig_eax >= 0) {
+		/* Restart the system call - no handlers present */
+		switch (regs->eax) {
+		case -ERESTARTNOHAND:
+		case -ERESTARTSYS:
+		case -ERESTARTNOINTR:
+			regs->eax = regs->orig_eax;
+			regs->eip -= 2;
+			break;
+
+		case -ERESTART_RESTARTBLOCK:
+			regs->eax = __NR_restart_syscall;
+			regs->eip -= 2;
+			break;
+		}
+	}
+
+	/* if there's no signal to deliver, we just put the saved sigmask
+	 * back */
+	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
+		clear_thread_flag(TIF_RESTORE_SIGMASK);
+		sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
+	}
+}
+
+/*
+ * notification of userspace execution resumption
+ * - triggered by the TIF_WORK_MASK flags
+ */
+__attribute__((regparm(3)))
+void do_notify_resume(struct pt_regs *regs, void *_unused,
+		      __u32 thread_info_flags)
+{
+	/* Pending single-step? */
+	if (thread_info_flags & _TIF_SINGLESTEP) {
+		regs->eflags |= TF_MASK;
+		clear_thread_flag(TIF_SINGLESTEP);
+	}
+
+	/* deal with pending signal delivery */
+	if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
+		do_signal(regs);
+	
+	clear_thread_flag(TIF_IRET);
+}