vserver 2.0 rc7

[linux-2.6.git] / arch / arm / mm / fault.c

diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 29be1c0..e25b4fd 100644 (file)
--- 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;
@@ -241,13 +243,6 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
        if (fault > 0)
                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.
@@ -255,42 +250,39 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
        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);