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

[Al Viro]

On Tue, Apr 21, 2020 at 09:01:48PM +0200, Christoph Hellwig wrote:
> 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.

Wait a bloody minute, it's doing *what* under a spinlock?