Re: [PATCH 08/10] x86/xsaves: Fix PTRACE frames for XSAVES

From: Andy Lutomirski
Date: Mon Feb 22 2016 - 17:46:18 EST


On Mon, Feb 22, 2016 at 11:00 AM, Yu-cheng Yu <yu-cheng.yu@xxxxxxxxx> wrote:
> XSAVES uses compacted format and is a kernel instruction. The kernel
> should use standard-format, non-supervisor state data for PTRACE.
>

> +/*
> + * Convert from kernel XSAVES compacted format to standard format and copy
> + * to a ptrace buffer. It supports partial copy but pos always starts from
> + * zero. This is called from xstateregs_get() and there we check the cpu
> + * has XSAVES.
> + */
> +int copyout_from_xsaves(unsigned int pos, unsigned int count, void *kbuf,
> + void __user *ubuf, const struct xregs_state *xsave)

Now that you've written this code, can it be shared with the signal
handling code?

--Andy


--Andy