Re: [PATCH 16/22] x86/fpu: Always store the registers in copy_fpstate_to_sigframe()

Sebastian Andrzej Siewior
2019-02-07T13:28:07Z

On 2019-01-30 12:43:22 [+0100], Borislav Petkov wrote:
> > @@ -171,9 +156,15 @@ int copy_fpstate_to_sigframe(void __user *buf, void __user *buf_fx, int size)
> > sizeof(struct user_i387_ia32_struct), NULL,
> > (struct _fpstate_32 __user *) buf) ? -1 : 1;
> >
> > - /* Save the live register state to the user directly. */
> > - if (copy_fpregs_to_sigframe(buf_fx))
> > - return -1;
> > + copy_fpregs_to_fpstate(fpu);
> > +
> > + if (using_compacted_format()) {
> > + copy_xstate_to_user(buf_fx, xsave, 0, size);
> > + } else {
> > + fpstate_sanitize_xstate(fpu);
> > + if (__copy_to_user(buf_fx, xsave, fpu_user_xstate_size))
> > + return -1;
> > + }
> >
> > /* Save the fsave header for the 32-bit frames. */
> > if ((ia32_fxstate || !use_fxsr()) && save_fsave_header(tsk, buf))
>
> Comments above that function need updating.

Did:
- * Save the state directly to the user frame pointed by the aligned pointer
- * 'buf_fx'.
+ * Save the state to task's fpu->state and then copy it to the user frame
+ * pointed by the aligned pointer 'buf_fx'.

Sebastian