1 files changed, 29 insertions, 18 deletions

diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index f6de76e0a45d..45e9ea6cd2a5 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -198,25 +198,16 @@ void show_stack(struct task_struct *tsk, unsigned long *sp)
         barrier();
 }
 
-DEFINE_SPINLOCK(die_lock);
-
-/*
- * This function is protected against re-entrancy.
- */
-NORET_TYPE void die(const char *str, struct pt_regs *regs, int err)
+static void __die(const char *str, int err, struct thread_info *thread, struct pt_regs *regs)
 {
-        struct task_struct *tsk = current;
+        struct task_struct *tsk = thread->task;
         static int die_counter;
 
-        console_verbose();
-        spin_lock_irq(&die_lock);
-        bust_spinlocks(1);
-
         printk("Internal error: %s: %x [#%d]\n", str, err, ++die_counter);
         print_modules();
         __show_regs(regs);
         printk("Process %s (pid: %d, stack limit = 0x%p)\n",
-                tsk->comm, tsk->pid, tsk->thread_info + 1);
+                tsk->comm, tsk->pid, thread + 1);
 
         if (!user_mode(regs) || in_interrupt()) {
                 dump_mem("Stack: ", regs->ARM_sp,
@@ -224,7 +215,21 @@ NORET_TYPE void die(const char *str, struct pt_regs *regs, int err)
                 dump_backtrace(regs, tsk);
                 dump_instr(regs);
         }
+}
+
+DEFINE_SPINLOCK(die_lock);
+
+/*
+ * This function is protected against re-entrancy.
+ */
+NORET_TYPE void die(const char *str, struct pt_regs *regs, int err)
+{
+        struct thread_info *thread = current_thread_info();
 
+        console_verbose();
+        spin_lock_irq(&die_lock);
+        bust_spinlocks(1);
+        __die(str, err, thread, regs);
         bust_spinlocks(0);
         spin_unlock_irq(&die_lock);
         do_exit(SIGSEGV);
@@ -345,7 +350,9 @@ static int bad_syscall(int n, struct pt_regs *regs)
         struct thread_info *thread = current_thread_info();
         siginfo_t info;
 
-        if (current->personality != PER_LINUX && thread->exec_domain->handler) {
+        if (current->personality != PER_LINUX &&
+            current->personality != PER_LINUX_32BIT &&
+            thread->exec_domain->handler) {
                 thread->exec_domain->handler(n, regs);
                 return regs->ARM_r0;
         }
@@ -481,29 +488,33 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs)
                 unsigned long addr = regs->ARM_r2;
                 struct mm_struct *mm = current->mm;
                 pgd_t *pgd; pmd_t *pmd; pte_t *pte;
+                spinlock_t *ptl;
 
                 regs->ARM_cpsr &= ~PSR_C_BIT;
-                spin_lock(&mm->page_table_lock);
+                down_read(&mm->mmap_sem);
                 pgd = pgd_offset(mm, addr);
                 if (!pgd_present(*pgd))
                         goto bad_access;
                 pmd = pmd_offset(pgd, addr);
                 if (!pmd_present(*pmd))
                         goto bad_access;
-                pte = pte_offset_map(pmd, addr);
-                if (!pte_present(*pte) || !pte_write(*pte))
+                pte = pte_offset_map_lock(mm, pmd, addr, &ptl);
+                if (!pte_present(*pte) || !pte_write(*pte)) {
+                        pte_unmap_unlock(pte, ptl);
                         goto bad_access;
+                }
                 val = *(unsigned long *)addr;
                 val -= regs->ARM_r0;
                 if (val == 0) {
                         *(unsigned long *)addr = regs->ARM_r1;
                         regs->ARM_cpsr |= PSR_C_BIT;
                 }
-                spin_unlock(&mm->page_table_lock);
+                pte_unmap_unlock(pte, ptl);
+                up_read(&mm->mmap_sem);
                 return val;
 
                 bad_access:
-                spin_unlock(&mm->page_table_lock);
+                up_read(&mm->mmap_sem);
                 /* simulate a write access fault */
                 do_DataAbort(addr, 15 + (1 << 11), regs);
                 return -1;