Re: [PATCH 1/7] powerpc/spufs: simplify spufs core dumping

[Christoph Hellwig]

On Tue, Apr 21, 2020 at 07:49:41PM +0100, Al Viro wrote:
> >  	spin_lock(&ctx->csa.register_lock);
> > -	ret = __spufs_proxydma_info_read(ctx, buf, len, pos);
> > +	__spufs_proxydma_info_read(ctx, &info);
> > +	ret = simple_read_from_buffer(buf, len, pos, &info, sizeof(info));
> 
> IDGI...  What's that access_ok() for?  If you are using simple_read_from_buffer(),
> the damn thing goes through copy_to_user().  Why bother with separate access_ok()
> here?

I have no idea at all, this just refactors the code.