Re: [Xen-devel] [PATCH RESEND] xen/gntdev: Grant maps should not be subject to NUMA balancing

From: David Vrabel
Date: Thu Nov 10 2016 - 12:49:31 EST


On 10/11/16 17:47, Olaf Hering wrote:
> On Thu, Nov 10, Boris Ostrovsky wrote:
>
>> Are you sure it's this patch that causes the failure?
>>
>> I commented out '| VM_IO' and still unable to boot with this option.
>
> Yes, this works for me, sles12sp2 dom0+domU, which is linux-4.4 based:
>
> +++ b/drivers/xen/gntdev.c
> @@ -804,7 +804,7 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
>
> vma->vm_ops = &gntdev_vmops;
>
> - vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP | VM_IO;
> + vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP /*| VM_IO*/;
>
> if (use_ptemod)
> vma->vm_flags |= VM_DONTCOPY;

I think we need a custom policy for this VMA with MPOL_F_MOF cleared.

David