[PATCH 2/6] shm: add sealing API

[David Herrmann]

Hi

On Sat, Apr 12, 2014 at 12:07 AM, Andy Lutomirski <luto at amacapital.net> wrote:
> I bet this is missing from lots of places.  For example, I can't find
> any write_access stuff in the rdma code.
>
> I suspect that the VM_DENYWRITE code is just generally racy.

So what does S_IMMUTABLE do to prevent such races? I somehow suspect
it's broken in that regard, too.

I really dislike pinning pages like this, but if people want to keep
it I guess I have to scan all shmem-inode pages before changing seals.

Thanks
David