[PATCH x86/mm 6/6] x86-64 ia32 ptrace get/putreg32 current task

Roland McGrath
2007-11-29T00:42:41Z

This generalizes the getreg32 and putreg32 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>
---
arch/x86/ia32/ptrace32.c | 16 ++++++++++++++++
1 files changed, 16 insertions(+), 0 deletions(-)

diff --git a/arch/x86/ia32/ptrace32.c b/arch/x86/ia32/ptrace32.c
index c52d066..d5663e2 100644
--- a/arch/x86/ia32/ptrace32.c
+++ b/arch/x86/ia32/ptrace32.c
@@ -48,19 +48,27 @@ static int putreg32(struct task_struct *child, unsigned regno, u32 val)
if (val && (val & 3) != 3)
return -EIO;
child->thread.fsindex = val & 0xffff;
+ if (child == current)
+ loadsegment(fs, child->thread.fsindex);
break;
case offsetof(struct user32, regs.gs):
if (val && (val & 3) != 3)
return -EIO;
child->thread.gsindex = val & 0xffff;
+ if (child == current)
+ load_gs_index(child->thread.gsindex);
break;
case offsetof(struct user32, regs.ds):
if (val && (val & 3) != 3)
return -EIO;
child->thread.ds = val & 0xffff;
+ if (child == current)
+ loadsegment(ds, child->thread.ds);
break;
case offsetof(struct user32, regs.es):
child->thread.es = val & 0xffff;
+ if (child == current)
+ loadsegment(es, child->thread.ds);
break;
case offsetof(struct user32, regs.ss):
if ((val & 3) != 3)
@@ -129,15 +137,23 @@ static int getreg32(struct task_struct *child, unsigned regno, u32 *val)
switch (regno) {
case offsetof(struct user32, regs.fs):
*val = child->thread.fsindex;
+ if (child == current)
+ asm("movl %%fs,%0" : "=r" (*val));
break;
case offsetof(struct user32, regs.gs):
*val = child->thread.gsindex;
+ if (child == current)
+ asm("movl %%gs,%0" : "=r" (*val));
break;
case offsetof(struct user32, regs.ds):
*val = child->thread.ds;
+ if (child == current)
+ asm("movl %%ds,%0" : "=r" (*val));
break;
case offsetof(struct user32, regs.es):
*val = child->thread.es;
+ if (child == current)
+ asm("movl %%es,%0" : "=r" (*val));
break;

R32(cs, cs);