[PATCH] x86_64: Use a common function to find code segment bases

To avoid some code duplication.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/arch/x86_64/mm/fault.c b/arch/x86_64/mm/fault.c
index d4676ca091449bd87c075956057716f57decd406..e0330921676413d100b6a1f2cf2c6f579133e3d8 100644 (file)
--- a/arch/x86_64/mm/fault.c
+++ b/arch/x86_64/mm/fault.c
@@ -62,21 +62,19 @@ void bust_spinlocks(int yes)
 static noinline int is_prefetch(struct pt_regs *regs, unsigned long addr,
                                unsigned long error_code)
 { 
-       unsigned char *instr = (unsigned char *)(regs->rip);
+       unsigned char *instr;
        int scan_more = 1;
        int prefetch = 0; 
-       unsigned char *max_instr = instr + 15;
+       unsigned char *max_instr;
 
        /* If it was a exec fault ignore */
        if (error_code & (1<<4))
                return 0;
        
-       /* Code segments in LDT could have a non zero base. Don't check
-          when that's possible */
-       if (regs->cs & (1<<2))
-               return 0;
+       instr = (unsigned char *)convert_rip_to_linear(current, regs);
+       max_instr = instr + 15;
 
-       if ((regs->cs & 3) != 0 && regs->rip >= TASK_SIZE)
+       if ((regs->cs & 3) != 0 && instr >= (unsigned char *)TASK_SIZE)
                return 0;
 
        while (scan_more && instr < max_instr) { 

diff --git a/include/asm-x86_64/ptrace.h b/include/asm-x86_64/ptrace.h
index c7865cfedc1fd7b44943ef30a423a27eb1b6f515..5bbc8d3141c86a1cbed6482854631b46a53caa73 100644 (file)
--- a/include/asm-x86_64/ptrace.h
+++ b/include/asm-x86_64/ptrace.h
@@ -86,6 +86,11 @@ struct pt_regs {
 extern unsigned long profile_pc(struct pt_regs *regs);
 void signal_fault(struct pt_regs *regs, void __user *frame, char *where);
 
+struct task_struct;
+
+extern unsigned long
+convert_rip_to_linear(struct task_struct *child, struct pt_regs *regs);
+
 enum {
         EF_CF   = 0x00000001,
         EF_PF   = 0x00000004,