x86: x86-32 ptrace get/putreg current task
This generalizes the getreg and putreg functions so they can be used on the
current task, as well as on a task stopped in TASK_TRACED and switched off.
This lays the groundwork to share this code for all kinds of user-mode
machine state access, not just ptrace.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/ptrace_32.c b/arch/x86/kernel/ptrace_32.c
index 5aca84e..2607130 100644
--- a/arch/x86/kernel/ptrace_32.c
+++ b/arch/x86/kernel/ptrace_32.c
@@ -55,6 +55,12 @@
if (value && (value & 3) != 3)
return -EIO;
child->thread.gs = value;
+ if (child == current)
+ /*
+ * The user-mode %gs is not affected by
+ * kernel entry, so we must update the CPU.
+ */
+ loadsegment(gs, value);
return 0;
case DS:
case ES:
@@ -104,6 +110,8 @@
break;
case GS:
retval = child->thread.gs;
+ if (child == current)
+ savesegment(gs, retval);
break;
case DS:
case ES: