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Diffstat (limited to 'arch/i386/mm/fault.c')
-rw-r--r--arch/i386/mm/fault.c29
1 files changed, 10 insertions, 19 deletions
diff --git a/arch/i386/mm/fault.c b/arch/i386/mm/fault.c
index f7279468323..2581575786c 100644
--- a/arch/i386/mm/fault.c
+++ b/arch/i386/mm/fault.c
@@ -27,21 +27,24 @@
#include <asm/uaccess.h>
#include <asm/desc.h>
#include <asm/kdebug.h>
+#include <asm/segment.h>
extern void die(const char *,struct pt_regs *,long);
-#ifdef CONFIG_KPROBES
-ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain);
+static 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);
}
+EXPORT_SYMBOL_GPL(register_page_fault_notifier);
int unregister_page_fault_notifier(struct notifier_block *nb)
{
return atomic_notifier_chain_unregister(&notify_page_fault_chain, nb);
}
+EXPORT_SYMBOL_GPL(unregister_page_fault_notifier);
static inline int notify_page_fault(enum die_val val, const char *str,
struct pt_regs *regs, long err, int trap, int sig)
@@ -55,14 +58,6 @@ static inline int notify_page_fault(enum die_val val, const char *str,
};
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
@@ -119,10 +114,10 @@ static inline unsigned long get_segment_eip(struct pt_regs *regs,
}
/* The standard kernel/user address space limit. */
- *eip_limit = (seg & 3) ? USER_DS.seg : KERNEL_DS.seg;
+ *eip_limit = user_mode(regs) ? USER_DS.seg : KERNEL_DS.seg;
/* By far the most common cases. */
- if (likely(seg == __USER_CS || seg == __KERNEL_CS))
+ if (likely(SEGMENT_IS_FLAT_CODE(seg)))
return eip;
/* Check the segment exists, is within the current LDT/GDT size,
@@ -436,11 +431,7 @@ good_area:
write = 0;
switch (error_code & 3) {
default: /* 3: write, present */
-#ifdef TEST_VERIFY_AREA
- if (regs->cs == KERNEL_CS)
- printk("WP fault at %08lx\n", regs->eip);
-#endif
- /* fall through */
+ /* fall through */
case 2: /* write, not present */
if (!(vma->vm_flags & VM_WRITE))
goto bad_area;
@@ -449,7 +440,7 @@ good_area:
case 1: /* read, present */
goto bad_area;
case 0: /* read, not present */
- if (!(vma->vm_flags & (VM_READ | VM_EXEC)))
+ if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)))
goto bad_area;
}
@@ -598,7 +589,7 @@ no_context:
*/
out_of_memory:
up_read(&mm->mmap_sem);
- if (tsk->pid == 1) {
+ if (is_init(tsk)) {
yield();
down_read(&mm->mmap_sem);
goto survive;