1 files changed, 36 insertions, 44 deletions

diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 29be1c018949..e25b4fd8412c 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -108,14 +108,15 @@ __do_kernel_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr,
  */
 static void
 __do_user_fault(struct task_struct *tsk, unsigned long addr,
-                unsigned int fsr, int code, struct pt_regs *regs)
+                unsigned int fsr, unsigned int sig, int code,
+                struct pt_regs *regs)
 {
         struct siginfo si;
 
 #ifdef CONFIG_DEBUG_USER
         if (user_debug & UDBG_SEGV) {
-                printk(KERN_DEBUG "%s: unhandled page fault at 0x%08lx, code 0x%03x\n",
-                       tsk->comm, addr, fsr);
+                printk(KERN_DEBUG "%s: unhandled page fault (%d) at 0x%08lx, code 0x%03x\n",
+                       tsk->comm, sig, addr, fsr);
                 show_pte(tsk->mm, addr);
                 show_regs(regs);
         }
@@ -124,11 +125,11 @@ __do_user_fault(struct task_struct *tsk, unsigned long addr,
         tsk->thread.address = addr;
         tsk->thread.error_code = fsr;
         tsk->thread.trap_no = 14;
-        si.si_signo = SIGSEGV;
+        si.si_signo = sig;
         si.si_errno = 0;
         si.si_code = code;
         si.si_addr = (void __user *)addr;
-        force_sig_info(SIGSEGV, &si, tsk);
+        force_sig_info(sig, &si, tsk);
 }
 
 void
@@ -140,7 +141,7 @@ do_bad_area(struct task_struct *tsk, struct mm_struct *mm, unsigned long addr,
          * have no context to handle this fault with.
          */
         if (user_mode(regs))
-                __do_user_fault(tsk, addr, fsr, SEGV_MAPERR, regs);
+                __do_user_fault(tsk, addr, fsr, SIGSEGV, SEGV_MAPERR, regs);
         else
                 __do_kernel_fault(mm, addr, fsr, regs);
 }
@@ -201,10 +202,11 @@ survive:
                 goto out;
 
         /*
-         * If we are out of memory for pid1,
-         * sleep for a while and retry
+         * If we are out of memory for pid1, sleep for a while and retry
          */
+        up_read(&mm->mmap_sem);
         yield();
+        down_read(&mm->mmap_sem);
         goto survive;
 
 check_stack:
@@ -219,7 +221,7 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 {
         struct task_struct *tsk;
         struct mm_struct *mm;
-        int fault;
+        int fault, sig, code;
 
         tsk = current;
         mm  = tsk->mm;
@@ -242,55 +244,45 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
                 return 0;
 
         /*
-         * We had some memory, but were unable to
-         * successfully fix up this page fault.
-         */
-        if (fault == 0)
-                goto do_sigbus;
-
-        /*
          * If we are in kernel mode at this point, we
          * have no context to handle this fault with.
          */
         if (!user_mode(regs))
                 goto no_context;
 
-        if (fault == VM_FAULT_OOM) {
+        switch (fault) {
+        case VM_FAULT_OOM:
                 /*
-                 * We ran out of memory, or some other thing happened to
-                 * us that made us unable to handle the page fault gracefully.
+                 * We ran out of memory, or some other thing
+                 * happened to us that made us unable to handle
+                 * the page fault gracefully.
                  */
                 printk("VM: killing process %s\n", tsk->comm);
                 do_exit(SIGKILL);
-        } else
-                __do_user_fault(tsk, addr, fsr, fault == VM_FAULT_BADACCESS ?
-                                SEGV_ACCERR : SEGV_MAPERR, regs);
-        return 0;
+                return 0;
 
+        case 0:
+                /*
+                 * We had some memory, but were unable to
+                 * successfully fix up this page fault.
+                 */
+                sig = SIGBUS;
+                code = BUS_ADRERR;
+                break;
 
-/*
- * We ran out of memory, or some other thing happened to us that made
- * us unable to handle the page fault gracefully.
- */
-do_sigbus:
-        /*
-         * Send a sigbus, regardless of whether we were in kernel
-         * or user mode.
-         */
-        tsk->thread.address = addr;
-        tsk->thread.error_code = fsr;
-        tsk->thread.trap_no = 14;
-        force_sig(SIGBUS, tsk);
-#ifdef CONFIG_DEBUG_USER
-        if (user_debug & UDBG_BUS) {
-                printk(KERN_DEBUG "%s: sigbus at 0x%08lx, pc=0x%08lx\n",
-                        current->comm, addr, instruction_pointer(regs));
+        default:
+                /*
+                 * Something tried to access memory that
+                 * isn't in our memory map..
+                 */
+                sig = SIGSEGV;
+                code = fault == VM_FAULT_BADACCESS ?
+                        SEGV_ACCERR : SEGV_MAPERR;
+                break;
         }
-#endif
 
-        /* Kernel mode? Handle exceptions or die */
-        if (user_mode(regs))
-                return 0;
+        __do_user_fault(tsk, addr, fsr, sig, code, regs);
+        return 0;
 
 no_context:
         __do_kernel_fault(mm, addr, fsr, regs);