Re: [PATCH v3] Add udmabuf misc device

From: Gerd Hoffmann
Date: Tue May 29 2018 - 06:49:04 EST


Hi,

> > > qemu test branch:
> > > https://git.kraxel.org/cgit/qemu/log/?h=sirius/udmabuf
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

> > > + if (!shmem_mapping(file_inode(ubuf->filp)->i_mapping))
> > > + goto err_free_ubuf;
>
> Can/should we test here that the memfd has a locked down size here?

Makes sense. Suggested way to check that? unstatic memfd_get_seals()
function (mm/shmem.c)? Or is there some better way?

Also which seals should we require? Is F_SEAL_SHRINK enough?

> On that: Link to userspace patches/git tree using this would be nice.

See above.

cheers,
Gerd