Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6

[pandora-kernel.git] / arch / i386 / mm / fault.c

diff --git a/arch/i386/mm/fault.c b/arch/i386/mm/fault.c
index f38085f..6ee7faa 100644 (file)
--- a/arch/i386/mm/fault.c
+++ b/arch/i386/mm/fault.c
@@ -30,6 +30,40 @@
 
 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 
@@ -77,12 +111,15 @@ 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))
@@ -321,7 +358,7 @@ 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_die(DIE_PAGE_FAULT, "page fault", regs, error_code, 14,
+               if (notify_page_fault(DIE_PAGE_FAULT, "page fault", regs, error_code, 14,
                                                SIGSEGV) == NOTIFY_STOP)
                        return;
                /*
@@ -331,7 +368,7 @@ fastcall void __kprobes do_page_fault(struct pt_regs *regs,
                goto bad_area_nosemaphore;
        }
 
-       if (notify_die(DIE_PAGE_FAULT, "page fault", regs, error_code, 14,
+       if (notify_page_fault(DIE_PAGE_FAULT, "page fault", regs, error_code, 14,
                                        SIGSEGV) == NOTIFY_STOP)
                return;