Re: [PATCH] [4.2 fix] x86, mpx: do not set ->vm_ops on mpx VMAs

[Greg KH <greg@kroah.com>]

On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote:
> 
> (sorry for the spam, I screwed up the stable@ address).
> 
> BTW, thanks to Kirill for doing this patch!  He posted it to LKML
> but we need to ensure it is picked up for 4.2 and any -stable
> kernels where this commit is applied:
> 
>     	6b7339f4: mm: avoid setting up anonymous pages into file mapping
> 
> That broke MPX support because MPX sets a vma->vm_ops on an
> anonymous VMA.  We need this patch to make it work again,
> basically removing MPX's use of ->vm_ops.  Kirill made me aware
> of this long ago, but I didn't double-check that his fix got
> submitted and merged.
> 
> I (Dave) fixed up a minor merge conflict and added the
> try_unmap_single_bt() use of is_mpx_vma() (which were added
> post-4.1).
> 
> Note for -stable: The first hunk may not apply cleanly because of
> other activity in arch/x86/mm/mmap.c, but should be trivial to
> apply by hand.  Hunk #5 on mpx.c is only present on 4.2-rc kernels.

Can someone send a version that is known to apply, you don't want to
rely on me to get it right :)

thanks,

greg k-h