1 files changed, 8 insertions, 13 deletions

diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index 06ca07f6ad86..3d9672e59c16 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -75,10 +75,7 @@ static inline bool invalid_selector(u16 value)
 static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long regno)
 {
         BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0);
-        regno >>= 2;
-        if (regno > FS)
-                --regno;
-        return &regs->bx + regno;
+        return &regs->bx + (regno >> 2);
 }
 
 static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
@@ -90,9 +87,10 @@ static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
         if (offset != offsetof(struct user_regs_struct, gs))
                 retval = *pt_regs_access(task_pt_regs(task), offset);
         else {
-                retval = task->thread.gs;
                 if (task == current)
-                        savesegment(gs, retval);
+                        retval = get_user_gs(task_pt_regs(task));
+                else
+                        retval = task_user_gs(task);
         }
         return retval;
 }
@@ -126,13 +124,10 @@ static int set_segment_reg(struct task_struct *task,
                 break;
 
         case offsetof(struct user_regs_struct, gs):
-                task->thread.gs = value;
                 if (task == current)
-                        /*
-                         * The user-mode %gs is not affected by
-                         * kernel entry, so we must update the CPU.
-                         */
-                        loadsegment(gs, value);
+                        set_user_gs(task_pt_regs(task), value);
+                else
+                        task_user_gs(task) = value;
         }
 
         return 0;
@@ -273,7 +268,7 @@ static unsigned long debugreg_addr_limit(struct task_struct *task)
         if (test_tsk_thread_flag(task, TIF_IA32))
                 return IA32_PAGE_OFFSET - 3;
 #endif
-        return TASK_SIZE64 - 7;
+        return TASK_SIZE_MAX - 7;
 }
 
 #endif  /* CONFIG_X86_32 */