Revert to Fedora kernel-2.6.17-1.2187_FC5 patched with vs2.0.2.1; there are too many...

[linux-2.6.git] / arch / i386 / mm / fault.c

diff --git a/arch/i386/mm/fault.c b/arch/i386/mm/fault.c
index f727946..7f0fcf2 100644 (file)
--- a/arch/i386/mm/fault.c
+++ b/arch/i386/mm/fault.c
@@ -30,40 +30,6 @@
 
 extern void die(const char *,struct pt_regs *,long);
 
-#ifdef CONFIG_KPROBES
-ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain);
-int register_page_fault_notifier(struct notifier_block *nb)
-{
-       vmalloc_sync_all();
-       return atomic_notifier_chain_register(&notify_page_fault_chain, nb);
-}
-
-int unregister_page_fault_notifier(struct notifier_block *nb)
-{
-       return atomic_notifier_chain_unregister(&notify_page_fault_chain, nb);
-}
-
-static inline int notify_page_fault(enum die_val val, const char *str,
-                       struct pt_regs *regs, long err, int trap, int sig)
-{
-       struct die_args args = {
-               .regs = regs,
-               .str = str,
-               .err = err,
-               .trapnr = trap,
-               .signr = sig
-       };
-       return atomic_notifier_call_chain(&notify_page_fault_chain, val, &args);
-}
-#else
-static inline int notify_page_fault(enum die_val val, const char *str,
-                       struct pt_regs *regs, long err, int trap, int sig)
-{
-       return NOTIFY_DONE;
-}
-#endif
-
-
 /*
  * Unlock any spinlocks which will prevent us from getting the
  * message out 
@@ -111,15 +77,12 @@ static inline unsigned long get_segment_eip(struct pt_regs *regs,
        unsigned seg = regs->xcs & 0xffff;
        u32 seg_ar, seg_limit, base, *desc;
 
-       /* Unlikely, but must come before segment checks. */
-       if (unlikely(regs->eflags & VM_MASK)) {
-               base = seg << 4;
-               *eip_limit = base + 0xffff;
-               return base + (eip & 0xffff);
-       }
-
        /* The standard kernel/user address space limit. */
        *eip_limit = (seg & 3) ? USER_DS.seg : KERNEL_DS.seg;
+
+       /* Unlikely, but must come before segment checks. */
+       if (unlikely((regs->eflags & VM_MASK) != 0))
+               return eip + (seg << 4);
        
        /* By far the most common cases. */
        if (likely(seg == __USER_CS || seg == __KERNEL_CS))
@@ -358,7 +321,7 @@ fastcall void __kprobes do_page_fault(struct pt_regs *regs,
        if (unlikely(address >= TASK_SIZE)) {
                if (!(error_code & 0x0000000d) && vmalloc_fault(address) >= 0)
                        return;
-               if (notify_page_fault(DIE_PAGE_FAULT, "page fault", regs, error_code, 14,
+               if (notify_die(DIE_PAGE_FAULT, "page fault", regs, error_code, 14,
                                                SIGSEGV) == NOTIFY_STOP)
                        return;
                /*
@@ -368,7 +331,7 @@ fastcall void __kprobes do_page_fault(struct pt_regs *regs,
                goto bad_area_nosemaphore;
        }
 
-       if (notify_page_fault(DIE_PAGE_FAULT, "page fault", regs, error_code, 14,
+       if (notify_die(DIE_PAGE_FAULT, "page fault", regs, error_code, 14,
                                        SIGSEGV) == NOTIFY_STOP)
                return;
 
@@ -389,7 +352,7 @@ fastcall void __kprobes do_page_fault(struct pt_regs *regs,
        /* When running in the kernel we expect faults to occur only to
         * addresses in user space.  All other faults represent errors in the
         * kernel and should generate an OOPS.  Unfortunatly, in the case of an
-        * erroneous fault occurring in a code path which already holds mmap_sem
+        * erroneous fault occuring in a code path which already holds mmap_sem
         * we will deadlock attempting to validate the fault against the
         * address space.  Luckily the kernel only validly references user
         * space from well defined areas of code, which are listed in the
@@ -417,12 +380,12 @@ fastcall void __kprobes do_page_fault(struct pt_regs *regs,
                goto bad_area;
        if (error_code & 4) {
                /*
-                * Accessing the stack below %esp is always a bug.
-                * The large cushion allows instructions like enter
-                * and pusha to work.  ("enter $65535,$31" pushes
-                * 32 pointers and then decrements %esp by 65535.)
+                * accessing the stack below %esp is always a bug.
+                * The "+ 32" is there due to some instructions (like
+                * pusha) doing post-decrement on the stack and that
+                * doesn't show up until later..
                 */
-               if (address + 65536 + 32 * sizeof(unsigned long) < regs->esp)
+               if (address + 32 < regs->esp)
                        goto bad_area;
        }
        if (expand_stack(vma, address))