Re: [Qemu-devel] [RFC PATCH 2/6] virtio/console: Add a failback for unstealable pipe buffer

[Borislav Petkov]

On Thu, Aug 09, 2012 at 02:33:12PM +0530, Amit Shah wrote:
> > @@ -807,9 +807,31 @@ static int pipe_to_sg(struct pipe_inode_info *pipe, 
> > struct pipe_buffer *buf,
> >  
> >             len = min(buf->len, sd->len);
> >             sg_set_page(&(sgl->sg[sgl->n]), buf->page, len, buf->offset);
> > -           sgl->n++;
> > -           sgl->len += len;
> > +   } else {
> > +           /* Failback to copying a page */
> > +           struct page *page = alloc_page(GFP_KERNEL);
> 
> I prefer zeroing out the page.  If there's not enough data to be
> filled in the page, the remaining data can be leaked to the host.

get_zeroed_page()?

-- 
Regards/Gruss,
Boris.

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