[RFC PATCH] powerpc/spufs: fix copy_to_user while atomic

[Christoph Hellwig]

On Tue, Apr 28, 2020 at 08:02:07PM +0800, Jeremy Kerr wrote:
> Currently, we may perform a copy_to_user (through
> simple_read_from_buffer()) while holding a context's register_lock,
> while accessing the context save area.
> 
> This change uses a temporary buffers for the context save area data,
> which we then pass to simple_read_from_buffer.
> 
> Signed-off-by: Jeremy Kerr <jk at ozlabs.org>
> ---
> 
> Christoph - this fixes the copy_to_user while atomic, hopefully with
> only minimal distruption to your series.

I recognize plenty of sniplets from that :)  Your patch looks good
to me:

Reviewed-by: Christoph Hellwig <hch at lst.de>