Re: [PATCH 2/4] vfio: vfio_pci_nvlink2: use mmgrab

[Alex Williamson]

On Tue, 7 Jan 2020 18:00:31 +0100 (CET)
Julia Lawall <julia.lawall@xxxxxxxx> wrote:

> On Mon, 6 Jan 2020, Alex Williamson wrote:
> 
> > On Sun, 29 Dec 2019 16:42:56 +0100
> > Julia Lawall <Julia.Lawall@xxxxxxxx> wrote:
> >  
> > > Mmgrab was introduced in commit f1f1007644ff ("mm: add new mmgrab()
> > > helper") and most of the kernel was updated to use it. Update a
> > > remaining file.
> > >
> > > The semantic patch that makes this change is as follows:
> > > (http://coccinelle.lip6.fr/)
> > >
> > > <smpl>
> > > @@ expression e; @@
> > > - atomic_inc(&e->mm_count);
> > > + mmgrab(e);
> > > </smpl>
> > >
> > > Signed-off-by: Julia Lawall <Julia.Lawall@xxxxxxxx>
> > >
> > > ---
> > >  drivers/vfio/pci/vfio_pci_nvlink2.c |    2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/vfio/pci/vfio_pci_nvlink2.c b/drivers/vfio/pci/vfio_pci_nvlink2.c
> > > index f2983f0f84be..43df10af7f66 100644
> > > --- a/drivers/vfio/pci/vfio_pci_nvlink2.c
> > > +++ b/drivers/vfio/pci/vfio_pci_nvlink2.c
> > > @@ -159,7 +159,7 @@ static int vfio_pci_nvgpu_mmap(struct vfio_pci_device *vdev,
> > >  	data->useraddr = vma->vm_start;
> > >  	data->mm = current->mm;
> > >
> > > -	atomic_inc(&data->mm->mm_count);
> > > +	mmgrab(data->mm);
> > >  	ret = (int) mm_iommu_newdev(data->mm, data->useraddr,
> > >  			vma_pages(vma), data->gpu_hpa, &data->mem);
> > >
> > >  
> >
> > Acked-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
> >
> > Thanks!  I'm assuming these will be routed via janitors tree, please
> > let me know if you intend me to grab these two vfio patches from the
> > series.  Thanks,  
> 
> Please take them directly.

Ok, I'll queue patches 2 & 3 for v5.6.  Thanks,

Alex