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Date:   Thu, 7 May 2020 17:47:44 -0400
From:   Peter Xu <peterx@redhat.com>
To:     Alex Williamson <alex.williamson@redhat.com>
Cc:     kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        cohuck@redhat.com, jgg@ziepe.ca
Subject: Re: [PATCH v2 2/3] vfio-pci: Fault mmaps to enable vma tracking
Message-ID: <20200507214744.GP228260@xz-x1>
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 <158871569380.15589.16950418949340311053.stgit@gimli.home>
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Hi, Alex,

On Tue, May 05, 2020 at 03:54:53PM -0600, Alex Williamson wrote:
> +/*
> + * Zap mmaps on open so that we can fault them in on access and therefore
> + * our vma_list only tracks mappings accessed since last zap.
> + */
> +static void vfio_pci_mmap_open(struct vm_area_struct *vma)
> +{
> +	zap_vma_ptes(vma, vma->vm_start, vma->vm_end - vma->vm_start);

A pure question: is this only a safety-belt or it is required in some known
scenarios?

In all cases:

Reviewed-by: Peter Xu <peterx@redhat.com>

Thanks,

-- 
Peter Xu