Re: [PATCH v7 00/14] KVM: mm: fd-based approach for supporting KVM guest private memory

[Kirill A . Shutemov]

On Fri, Sep 02, 2022 at 06:27:57PM +0800, Chao Peng wrote:
> > +   if (flags & MFD_INACCESSIBLE) {
> > +           struct file *inaccessible_file;
> > +
> > +           inaccessible_file = memfd_mkinaccessible(file);
> > +           if (IS_ERR(inaccessible_file)) {
> > +                   error = PTR_ERR(inaccessible_file);
> > +                   goto err_file;
> > +           }
> 
> The new file should alse be marked as O_LARGEFILE otherwise setting the
> initial size greater than 2^31 on the fd will be refused by ftruncate().
> 
> +               inaccessible_file->f_flags |= O_LARGEFILE;
> +

Good catch. Thanks.

I will modify memfd_mkinaccessible() to do this.

-- 
  Kiryl Shutsemau / Kirill A. Shutemov