>
> * Roland McGrath <roland@redhat.com> wrote:
>
> > ptrace has always returned only -EIO for all failures to access
> > registers. The user_regset calls are allowed to return a more
> > meaningful variety of errors. The REGSET_XFP calls use -ENODEV for
> > !cpu_has_fxsr hardware. Make ptrace return the traditional -EIO
> > instead of the error code from the user_regset call.
>
> since the original fix is already upstream, i've applied the delta patch
> below. Should we still do this for v2.6.26 or can we defer it to
> v2.6.27? As ptrace is the only user of this facility for now this would
> be an identity transformation AFAICS and the v2.6.26 release is very
> close.
>
> Ingo
>
> ---------------->
> Subject: x86 ptrace: fix PTRACE_GETFPXREGS error
> From: Roland McGrath <roland@redhat.com>
> Date: Mon, 30 Jun 2008 14:02:41 -0700 (PDT)
>
> ptrace has always returned only -EIO for all failures to access
> registers. The user_regset calls are allowed to return a more
> meaningful variety of errors. The REGSET_XFP calls use -ENODEV
> for !cpu_has_fxsr hardware. Make ptrace return the traditional
> -EIO instead of the error code from the user_regset call.
>
> Signed-off-by: Roland McGrath <roland@redhat.com>
> Cc:
stable@kernel.org
> Signed-off-by: Ingo Molnar <mingo@elte.hu>
> ---
> arch/x86/kernel/i387.c | 4 ++--
> arch/x86/kernel/ptrace.c | 4 ++--
> 2 files changed, 4 insertions(+), 4 deletions(-)
>
> Index: tip/arch/x86/kernel/i387.c
> ===================================================================
> --- tip.orig/arch/x86/kernel/i387.c
> +++ tip/arch/x86/kernel/i387.c
> @@ -162,7 +162,7 @@ int xfpregs_get(struct task_struct *targ
> int ret;
>
> if (!cpu_has_fxsr)
> - return -EIO;
> + return -ENODEV;
>
> ret = init_fpu(target);
> if (ret)
> @@ -179,7 +179,7 @@ int xfpregs_set(struct task_struct *targ
> int ret;
>
> if (!cpu_has_fxsr)
> - return -EIO;
> + return -ENODEV;
>
> ret = init_fpu(target);
> if (ret)
> Index: tip/arch/x86/kernel/ptrace.c
> ===================================================================
> --- tip.orig/arch/x86/kernel/ptrace.c
> +++ tip/arch/x86/kernel/ptrace.c
> @@ -943,13 +943,13 @@ long arch_ptrace(struct task_struct *chi
> return copy_regset_to_user(child, &user_x86_32_view,
> REGSET_XFP,
> 0, sizeof(struct user_fxsr_struct),
> - datap);
> + datap) ? -EIO : 0;
>
> case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
> return copy_regset_from_user(child, &user_x86_32_view,
> REGSET_XFP,
> 0, sizeof(struct user_fxsr_struct),
> - datap);
> + datap) ? -EIO : 0;
> #endif
>
> #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
