Merge master.kernel.org:/home/rmk/linux-2.6-arm

[pandora-kernel.git] / arch / x86_64 / mm / fault.c

diff --git a/arch/x86_64/mm/fault.c b/arch/x86_64/mm/fault.c
index 5525059..08dc696 100644 (file)
--- a/arch/x86_64/mm/fault.c
+++ b/arch/x86_64/mm/fault.c
@@ -41,6 +41,41 @@
 #define PF_RSVD        (1<<3)
 #define PF_INSTR       (1<<4)
 
+#ifdef CONFIG_KPROBES
+ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain);
+
+/* Hook to register for page fault notifications */
+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
+
 void bust_spinlocks(int yes)
 {
        int loglevel_save = console_loglevel;
@@ -160,7 +195,7 @@ void dump_pagetable(unsigned long address)
        printk("PGD %lx ", pgd_val(*pgd));
        if (!pgd_present(*pgd)) goto ret; 
 
-       pud = __pud_offset_k((pud_t *)pgd_page(*pgd), address);
+       pud = pud_offset(pgd, address);
        if (bad_address(pud)) goto bad;
        printk("PUD %lx ", pud_val(*pud));
        if (!pud_present(*pud)) goto ret;
@@ -348,7 +383,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
                        if (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;
                /*
@@ -358,7 +393,7 @@ asmlinkage 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;
 
@@ -410,8 +445,10 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
        if (!(vma->vm_flags & VM_GROWSDOWN))
                goto bad_area;
        if (error_code & 4) {
-               // XXX: align red zone size with ABI 
-               if (address + 128 < regs->rsp)
+               /* Allow userspace just enough access below the stack pointer
+                * to let the 'enter' instruction work.
+                */
+               if (address + 65536 + 32 * sizeof(unsigned long) < regs->rsp)
                        goto bad_area;
        }
        if (expand_stack(vma, address))