[PATCH] i386: Use probe_kernel_address instead of __get_user in fault paths

Makes the intention of the code cleaner to read and avoids
a potential deadlock on mmap_sem. Also change the types of
the arguments to not include __user because they're really
not user addresses.

Signed-off-by: Andi Kleen <ak@suse.de>

1 files changed, 6 insertions, 6 deletions

diff --git a/arch/i386/mm/fault.c b/arch/i386/mm/fault.c
index 2581575786c1..aaaa4d225f7e 100644
--- a/arch/i386/mm/fault.c
+++ b/arch/i386/mm/fault.c
@@ -22,9 +22,9 @@
 #include <linux/highmem.h>
 #include <linux/module.h>
 #include <linux/kprobes.h>
+#include <linux/uaccess.h>
 
 #include <asm/system.h>
-#include <asm/uaccess.h>
 #include <asm/desc.h>
 #include <asm/kdebug.h>
 #include <asm/segment.h>
@@ -167,7 +167,7 @@ static inline unsigned long get_segment_eip(struct pt_regs *regs,
 static int __is_prefetch(struct pt_regs *regs, unsigned long addr)
 { 
         unsigned long limit;
-        unsigned long instr = get_segment_eip (regs, &limit);
+        unsigned char *instr = (unsigned char *)get_segment_eip (regs, &limit);
         int scan_more = 1;
         int prefetch = 0; 
         int i;
@@ -177,9 +177,9 @@ static int __is_prefetch(struct pt_regs *regs, unsigned long addr)
                 unsigned char instr_hi;
                 unsigned char instr_lo;
 
-                if (instr > limit)
+                if (instr > (unsigned char *)limit)
                         break;
-                if (__get_user(opcode, (unsigned char __user *) instr))
+                if (probe_kernel_address(instr, opcode))
                         break; 
 
                 instr_hi = opcode & 0xf0; 
@@ -204,9 +204,9 @@ static int __is_prefetch(struct pt_regs *regs, unsigned long addr)
                 case 0x00:
                         /* Prefetch instruction is 0x0F0D or 0x0F18 */
                         scan_more = 0;
-                        if (instr > limit)
+                        if (instr > (unsigned char *)limit)
                                 break;
-                        if (__get_user(opcode, (unsigned char __user *) instr))
+                        if (probe_kernel_address(instr, opcode))
                                 break;
                         prefetch = (instr_lo == 0xF) &&
                                 (opcode == 0x0D || opcode == 0x18);