Merge branch 'topic/core-cleanup' into for-linus
[safe/jmp/linux-2.6] / arch / arm / kernel / signal.c
index 652bb1a..907d5a6 100644 (file)
@@ -1,22 +1,24 @@
 /*
  *  linux/arch/arm/kernel/signal.c
  *
- *  Copyright (C) 1995-2002 Russell King
+ *  Copyright (C) 1995-2009 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 <linux/freezer.h>
+#include <linux/uaccess.h>
+#include <linux/tracehook.h>
 
+#include <asm/elf.h>
 #include <asm/cacheflush.h>
 #include <asm/ucontext.h>
-#include <asm/uaccess.h>
 #include <asm/unistd.h>
+#include <asm/vfp.h>
 
 #include "ptrace.h"
 #include "signal.h"
@@ -26,8 +28,9 @@
 /*
  * 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))
+#define SWI_SYS_SIGRETURN      (0xef000000|(__NR_sigreturn)|(__NR_OABI_SYSCALL_BASE))
+#define SWI_SYS_RT_SIGRETURN   (0xef000000|(__NR_rt_sigreturn)|(__NR_OABI_SYSCALL_BASE))
+#define SWI_SYS_RESTART                (0xef000000|__NR_restart_syscall|__NR_OABI_SYSCALL_BASE)
 
 /*
  * With EABI, the syscall number has to be loaded into r7.
@@ -47,57 +50,34 @@ const unsigned long sigreturn_codes[7] = {
        MOV_R7_NR_RT_SIGRETURN, SWI_SYS_RT_SIGRETURN, SWI_THUMB_RT_SIGRETURN,
 };
 
-static int do_signal(sigset_t *oldset, struct pt_regs * regs, int syscall);
+/*
+ * Either we support 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.
+ */
+const unsigned long syscall_restart_code[2] = {
+       SWI_SYS_RESTART,        /* swi  __NR_restart_syscall */
+       0xe49df004,             /* ldr  pc, [sp], #4 */
+};
 
 /*
  * 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)
+asmlinkage int sys_sigsuspend(int restart, unsigned long oldmask, old_sigset_t mask)
 {
-       sigset_t saveset;
-
        mask &= _BLOCKABLE;
        spin_lock_irq(&current->sighand->siglock);
-       saveset = current->blocked;
+       current->saved_sigmask = 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;
-       }
+       current->state = TASK_INTERRUPTIBLE;
+       schedule();
+       set_restore_sigmask();
+       return -ERESTARTNOHAND;
 }
 
 asmlinkage int 
@@ -132,18 +112,38 @@ sys_sigaction(int sig, const struct old_sigaction __user *act,
        return ret;
 }
 
-#ifdef CONFIG_IWMMXT
+#ifdef CONFIG_CRUNCH
+static int preserve_crunch_context(struct crunch_sigframe __user *frame)
+{
+       char kbuf[sizeof(*frame) + 8];
+       struct crunch_sigframe *kframe;
 
-/* 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
+       /* the crunch context must be 64 bit aligned */
+       kframe = (struct crunch_sigframe *)((unsigned long)(kbuf + 8) & ~7);
+       kframe->magic = CRUNCH_MAGIC;
+       kframe->size = CRUNCH_STORAGE_SIZE;
+       crunch_task_copy(current_thread_info(), &kframe->storage);
+       return __copy_to_user(frame, kframe, sizeof(*frame));
+}
 
-struct iwmmxt_sigframe {
-       unsigned long   magic0;
-       unsigned long   magic1;
-       unsigned long   storage[0x98/4];
-};
+static int restore_crunch_context(struct crunch_sigframe __user *frame)
+{
+       char kbuf[sizeof(*frame) + 8];
+       struct crunch_sigframe *kframe;
+
+       /* the crunch context must be 64 bit aligned */
+       kframe = (struct crunch_sigframe *)((unsigned long)(kbuf + 8) & ~7);
+       if (__copy_from_user(kframe, frame, sizeof(*frame)))
+               return -1;
+       if (kframe->magic != CRUNCH_MAGIC ||
+           kframe->size != CRUNCH_STORAGE_SIZE)
+               return -1;
+       crunch_task_restore(current_thread_info(), &kframe->storage);
+       return 0;
+}
+#endif
+
+#ifdef CONFIG_IWMMXT
 
 static int preserve_iwmmxt_context(struct iwmmxt_sigframe *frame)
 {
@@ -152,8 +152,8 @@ static int preserve_iwmmxt_context(struct iwmmxt_sigframe *frame)
 
        /* the iWMMXt context must be 64 bit aligned */
        kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7);
-       kframe->magic0 = IWMMXT_MAGIC0;
-       kframe->magic1 = IWMMXT_MAGIC1;
+       kframe->magic = IWMMXT_MAGIC;
+       kframe->size = IWMMXT_STORAGE_SIZE;
        iwmmxt_task_copy(current_thread_info(), &kframe->storage);
        return __copy_to_user(frame, kframe, sizeof(*frame));
 }
@@ -167,8 +167,8 @@ static int restore_iwmmxt_context(struct iwmmxt_sigframe *frame)
        kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7);
        if (__copy_from_user(kframe, frame, sizeof(*frame)))
                return -1;
-       if (kframe->magic0 != IWMMXT_MAGIC0 ||
-           kframe->magic1 != IWMMXT_MAGIC1)
+       if (kframe->magic != IWMMXT_MAGIC ||
+           kframe->size != IWMMXT_STORAGE_SIZE)
                return -1;
        iwmmxt_task_restore(current_thread_info(), &kframe->storage);
        return 0;
@@ -176,18 +176,89 @@ static int restore_iwmmxt_context(struct iwmmxt_sigframe *frame)
 
 #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;
+
+static int preserve_vfp_context(struct vfp_sigframe __user *frame)
+{
+       struct thread_info *thread = current_thread_info();
+       struct vfp_hard_struct *h = &thread->vfpstate.hard;
+       const unsigned long magic = VFP_MAGIC;
+       const unsigned long size = VFP_STORAGE_SIZE;
+       int err = 0;
+
+       vfp_sync_hwstate(thread);
+       __put_user_error(magic, &frame->magic, err);
+       __put_user_error(size, &frame->size, err);
+
+       /*
+        * Copy the floating point registers. There can be unused
+        * registers see asm/hwcap.h for details.
+        */
+       err |= __copy_to_user(&frame->ufp.fpregs, &h->fpregs,
+                             sizeof(h->fpregs));
+       /*
+        * Copy the status and control register.
+        */
+       __put_user_error(h->fpscr, &frame->ufp.fpscr, err);
+
+       /*
+        * Copy the exception registers.
+        */
+       __put_user_error(h->fpexc, &frame->ufp_exc.fpexc, err);
+       __put_user_error(h->fpinst, &frame->ufp_exc.fpinst, err);
+       __put_user_error(h->fpinst2, &frame->ufp_exc.fpinst2, err);
+
+       return err ? -EFAULT : 0;
+}
+
+static int restore_vfp_context(struct vfp_sigframe __user *frame)
+{
+       struct thread_info *thread = current_thread_info();
+       struct vfp_hard_struct *h = &thread->vfpstate.hard;
+       unsigned long magic;
+       unsigned long size;
+       unsigned long fpexc;
+       int err = 0;
+
+       __get_user_error(magic, &frame->magic, err);
+       __get_user_error(size, &frame->size, err);
+
+       if (err)
+               return -EFAULT;
+       if (magic != VFP_MAGIC || size != VFP_STORAGE_SIZE)
+               return -EINVAL;
+
+       /*
+        * Copy the floating point registers. There can be unused
+        * registers see asm/hwcap.h for details.
+        */
+       err |= __copy_from_user(&h->fpregs, &frame->ufp.fpregs,
+                               sizeof(h->fpregs));
+       /*
+        * Copy the status and control register.
+        */
+       __get_user_error(h->fpscr, &frame->ufp.fpscr, err);
+
+       /*
+        * Sanitise and restore the exception registers.
+        */
+       __get_user_error(fpexc, &frame->ufp_exc.fpexc, err);
+       /* Ensure the VFP is enabled. */
+       fpexc |= FPEXC_EN;
+       /* Ensure FPINST2 is invalid and the exception flag is cleared. */
+       fpexc &= ~(FPEXC_EX | FPEXC_FP2V);
+       h->fpexc = fpexc;
+
+       __get_user_error(h->fpinst, &frame->ufp_exc.fpinst, err);
+       __get_user_error(h->fpinst2, &frame->ufp_exc.fpinst2, err);
+
+       if (!err)
+               vfp_flush_hwstate(thread);
+
+       return err ? -EFAULT : 0;
+}
+
 #endif
-};
 
 /*
  * Do a signal return; undo the signal stack.  These are aligned to 64-bit.
@@ -195,7 +266,6 @@ struct aux_sigframe {
 struct sigframe {
        struct ucontext uc;
        unsigned long retcode[2];
-       struct aux_sigframe aux __attribute__((aligned(8)));
 };
 
 struct rt_sigframe {
@@ -203,39 +273,53 @@ struct rt_sigframe {
        struct sigframe sig;
 };
 
-static int
-restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
-                  struct aux_sigframe __user *aux)
+static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf)
 {
-       int err = 0;
+       struct aux_sigframe __user *aux;
+       sigset_t set;
+       int err;
+
+       err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set));
+       if (err == 0) {
+               sigdelsetmask(&set, ~_BLOCKABLE);
+               spin_lock_irq(&current->sighand->siglock);
+               current->blocked = set;
+               recalc_sigpending();
+               spin_unlock_irq(&current->sighand->siglock);
+       }
 
-       __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);
+       __get_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err);
+       __get_user_error(regs->ARM_r1, &sf->uc.uc_mcontext.arm_r1, err);
+       __get_user_error(regs->ARM_r2, &sf->uc.uc_mcontext.arm_r2, err);
+       __get_user_error(regs->ARM_r3, &sf->uc.uc_mcontext.arm_r3, err);
+       __get_user_error(regs->ARM_r4, &sf->uc.uc_mcontext.arm_r4, err);
+       __get_user_error(regs->ARM_r5, &sf->uc.uc_mcontext.arm_r5, err);
+       __get_user_error(regs->ARM_r6, &sf->uc.uc_mcontext.arm_r6, err);
+       __get_user_error(regs->ARM_r7, &sf->uc.uc_mcontext.arm_r7, err);
+       __get_user_error(regs->ARM_r8, &sf->uc.uc_mcontext.arm_r8, err);
+       __get_user_error(regs->ARM_r9, &sf->uc.uc_mcontext.arm_r9, err);
+       __get_user_error(regs->ARM_r10, &sf->uc.uc_mcontext.arm_r10, err);
+       __get_user_error(regs->ARM_fp, &sf->uc.uc_mcontext.arm_fp, err);
+       __get_user_error(regs->ARM_ip, &sf->uc.uc_mcontext.arm_ip, err);
+       __get_user_error(regs->ARM_sp, &sf->uc.uc_mcontext.arm_sp, err);
+       __get_user_error(regs->ARM_lr, &sf->uc.uc_mcontext.arm_lr, err);
+       __get_user_error(regs->ARM_pc, &sf->uc.uc_mcontext.arm_pc, err);
+       __get_user_error(regs->ARM_cpsr, &sf->uc.uc_mcontext.arm_cpsr, err);
 
        err |= !valid_user_regs(regs);
 
+       aux = (struct aux_sigframe __user *) sf->uc.uc_regspace;
+#ifdef CONFIG_CRUNCH
+       if (err == 0)
+               err |= restore_crunch_context(&aux->crunch);
+#endif
 #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);
+       if (err == 0)
+               err |= restore_vfp_context(&aux->vfp);
 #endif
 
        return err;
@@ -244,7 +328,6 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
 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;
@@ -261,23 +344,11 @@ asmlinkage int sys_sigreturn(struct pt_regs *regs)
 
        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))
+       if (restore_sigframe(regs, frame))
                goto badframe;
 
-       /* Send SIGTRAP if we're single-stepping */
-       if (current->ptrace & PT_SINGLESTEP) {
-               ptrace_cancel_bpt(current);
-               send_sig(SIGTRAP, current, 1);
-       }
+       single_step_trap(current);
 
        return regs->ARM_r0;
 
@@ -289,7 +360,6 @@ badframe:
 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;
@@ -306,26 +376,14 @@ asmlinkage int sys_rt_sigreturn(struct pt_regs *regs)
 
        if (!access_ok(VERIFY_READ, frame, sizeof (*frame)))
                goto badframe;
-       if (__copy_from_user(&set, &frame->sig.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->sig.uc.uc_mcontext, &frame->sig.aux))
+       if (restore_sigframe(regs, &frame->sig))
                goto badframe;
 
        if (do_sigaltstack(&frame->sig.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);
-       }
+       single_step_trap(current);
 
        return regs->ARM_r0;
 
@@ -335,42 +393,50 @@ badframe:
 }
 
 static int
-setup_sigcontext(struct sigcontext __user *sc, struct aux_sigframe __user *aux,
-                struct pt_regs *regs, unsigned long mask)
+setup_sigframe(struct sigframe __user *sf, struct pt_regs *regs, sigset_t *set)
 {
+       struct aux_sigframe __user *aux;
        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);
-
+       __put_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err);
+       __put_user_error(regs->ARM_r1, &sf->uc.uc_mcontext.arm_r1, err);
+       __put_user_error(regs->ARM_r2, &sf->uc.uc_mcontext.arm_r2, err);
+       __put_user_error(regs->ARM_r3, &sf->uc.uc_mcontext.arm_r3, err);
+       __put_user_error(regs->ARM_r4, &sf->uc.uc_mcontext.arm_r4, err);
+       __put_user_error(regs->ARM_r5, &sf->uc.uc_mcontext.arm_r5, err);
+       __put_user_error(regs->ARM_r6, &sf->uc.uc_mcontext.arm_r6, err);
+       __put_user_error(regs->ARM_r7, &sf->uc.uc_mcontext.arm_r7, err);
+       __put_user_error(regs->ARM_r8, &sf->uc.uc_mcontext.arm_r8, err);
+       __put_user_error(regs->ARM_r9, &sf->uc.uc_mcontext.arm_r9, err);
+       __put_user_error(regs->ARM_r10, &sf->uc.uc_mcontext.arm_r10, err);
+       __put_user_error(regs->ARM_fp, &sf->uc.uc_mcontext.arm_fp, err);
+       __put_user_error(regs->ARM_ip, &sf->uc.uc_mcontext.arm_ip, err);
+       __put_user_error(regs->ARM_sp, &sf->uc.uc_mcontext.arm_sp, err);
+       __put_user_error(regs->ARM_lr, &sf->uc.uc_mcontext.arm_lr, err);
+       __put_user_error(regs->ARM_pc, &sf->uc.uc_mcontext.arm_pc, err);
+       __put_user_error(regs->ARM_cpsr, &sf->uc.uc_mcontext.arm_cpsr, err);
+
+       __put_user_error(current->thread.trap_no, &sf->uc.uc_mcontext.trap_no, err);
+       __put_user_error(current->thread.error_code, &sf->uc.uc_mcontext.error_code, err);
+       __put_user_error(current->thread.address, &sf->uc.uc_mcontext.fault_address, err);
+       __put_user_error(set->sig[0], &sf->uc.uc_mcontext.oldmask, err);
+
+       err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set));
+
+       aux = (struct aux_sigframe __user *) sf->uc.uc_regspace;
+#ifdef CONFIG_CRUNCH
+       if (err == 0)
+               err |= preserve_crunch_context(&aux->crunch);
+#endif
 #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);
+       if (err == 0)
+               err |= preserve_vfp_context(&aux->vfp);
 #endif
+       __put_user_error(0, &aux->end_magic, err);
 
        return err;
 }
@@ -424,9 +490,13 @@ setup_return(struct pt_regs *regs, struct k_sigaction *ka,
                 */
                thumb = handler & 1;
 
-               if (thumb)
+               if (thumb) {
                        cpsr |= PSR_T_BIT;
-               else
+#if __LINUX_ARM_ARCH__ >= 7
+                       /* clear the If-Then Thumb-2 execution state */
+                       cpsr &= ~PSR_IT_MASK;
+#endif
+               } else
                        cpsr &= ~PSR_T_BIT;
        }
 #endif
@@ -479,9 +549,12 @@ setup_frame(int usig, struct k_sigaction *ka, sigset_t *set, struct pt_regs *reg
        if (!frame)
                return 1;
 
-       err |= setup_sigcontext(&frame->uc.uc_mcontext, &frame->aux, regs, set->sig[0]);
-       err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+       /*
+        * Set uc.uc_flags to a value which sc.trap_no would never have.
+        */
+       __put_user_error(0x5ac3c35a, &frame->uc.uc_flags, err);
 
+       err |= setup_sigframe(frame, regs, set);
        if (err == 0)
                err = setup_return(regs, ka, frame->retcode, frame, usig);
 
@@ -510,10 +583,7 @@ setup_rt_frame(int usig, struct k_sigaction *ka, siginfo_t *info,
        stack.ss_size = current->sas_ss_size;
        err |= __copy_to_user(&frame->sig.uc.uc_stack, &stack, sizeof(stack));
 
-       err |= setup_sigcontext(&frame->sig.uc.uc_mcontext, &frame->sig.aux,
-                               regs, set->sig[0]);
-       err |= __copy_to_user(&frame->sig.uc.uc_sigmask, set, sizeof(*set));
-
+       err |= setup_sigframe(&frame->sig, regs, set);
        if (err == 0)
                err = setup_return(regs, ka, frame->sig.retcode, frame, usig);
 
@@ -530,7 +600,7 @@ setup_rt_frame(int usig, struct k_sigaction *ka, siginfo_t *info,
        return err;
 }
 
-static inline void restart_syscall(struct pt_regs *regs)
+static inline void setup_syscall_restart(struct pt_regs *regs)
 {
        regs->ARM_r0 = regs->ARM_ORIG_r0;
        regs->ARM_pc -= thumb_mode(regs) ? 2 : 4;
@@ -539,7 +609,7 @@ static inline void restart_syscall(struct pt_regs *regs)
 /*
  * OK, we're invoking a handler
  */    
-static void
+static int
 handle_signal(unsigned long sig, struct k_sigaction *ka,
              siginfo_t *info, sigset_t *oldset,
              struct pt_regs * regs, int syscall)
@@ -565,7 +635,7 @@ handle_signal(unsigned long sig, struct k_sigaction *ka,
                        }
                        /* fallthrough */
                case -ERESTARTNOINTR:
-                       restart_syscall(regs);
+                       setup_syscall_restart(regs);
                }
        }
 
@@ -590,7 +660,7 @@ handle_signal(unsigned long sig, struct k_sigaction *ka,
 
        if (ret != 0) {
                force_sigsegv(sig, tsk);
-               return;
+               return ret;
        }
 
        /*
@@ -604,6 +674,7 @@ handle_signal(unsigned long sig, struct k_sigaction *ka,
        recalc_sigpending();
        spin_unlock_irq(&tsk->sighand->siglock);
 
+       return 0;
 }
 
 /*
@@ -615,7 +686,7 @@ handle_signal(unsigned long sig, struct k_sigaction *ka,
  * 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)
+static void do_signal(struct pt_regs *regs, int syscall)
 {
        struct k_sigaction ka;
        siginfo_t info;
@@ -628,20 +699,33 @@ static int do_signal(sigset_t *oldset, struct pt_regs *regs, int syscall)
         * if so.
         */
        if (!user_mode(regs))
-               return 0;
+               return;
 
        if (try_to_freeze())
                goto no_signal;
 
-       if (current->ptrace & PT_SINGLESTEP)
-               ptrace_cancel_bpt(current);
+       single_step_clear(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;
+               sigset_t *oldset;
+
+               if (test_thread_flag(TIF_RESTORE_SIGMASK))
+                       oldset = &current->saved_sigmask;
+               else
+                       oldset = &current->blocked;
+               if (handle_signal(signr, &ka, &info, oldset, regs, syscall) == 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);
+               }
+               single_step_set(current);
+               return;
        }
 
  no_signal:
@@ -651,40 +735,54 @@ static int do_signal(sigset_t *oldset, struct pt_regs *regs, int syscall)
        if (syscall) {
                if (regs->ARM_r0 == -ERESTART_RESTARTBLOCK) {
                        if (thumb_mode(regs)) {
-                               regs->ARM_r7 = __NR_restart_syscall;
+                               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;
 
-                               regs->ARM_sp -= 12;
+                               regs->ARM_sp -= 4;
                                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 (put_user(regs->ARM_pc, usp) == 0) {
+                                       regs->ARM_pc = KERN_RESTART_CODE;
+                               } else {
+                                       regs->ARM_sp += 4;
+                                       force_sigsegv(0, current);
+                               }
+#endif
                        }
                }
                if (regs->ARM_r0 == -ERESTARTNOHAND ||
                    regs->ARM_r0 == -ERESTARTSYS ||
                    regs->ARM_r0 == -ERESTARTNOINTR) {
-                       restart_syscall(regs);
+                       setup_syscall_restart(regs);
+               }
+
+               /* 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);
                }
        }
-       if (current->ptrace & PT_SINGLESTEP)
-               ptrace_set_bpt(current);
-       return 0;
+       single_step_set(current);
 }
 
 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);
+               do_signal(regs, syscall);
+
+       if (thread_flags & _TIF_NOTIFY_RESUME) {
+               clear_thread_flag(TIF_NOTIFY_RESUME);
+               tracehook_notify_resume(regs);
+               if (current->replacement_session_keyring)
+                       key_replace_session_keyring();
+       }
 }