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Date:   Thu, 17 Sep 2020 13:35:37 +0200
From:   Cornelia Huck <cohuck@redhat.com>
To:     Zenghui Yu <yuzenghui@huawei.com>
Cc:     <kvm@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <alex.williamson@redhat.com>, <wanghaibin.wang@huawei.com>
Subject: Re: [PATCH 2/2] vfio/pci: Remove bardirty from vfio_pci_device
Message-ID: <20200917133537.17af2ef3.cohuck@redhat.com>
In-Reply-To: <20200917033128.872-2-yuzenghui@huawei.com>
References: <20200917033128.872-1-yuzenghui@huawei.com>
        <20200917033128.872-2-yuzenghui@huawei.com>
Organization: Red Hat GmbH
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On Thu, 17 Sep 2020 11:31:28 +0800
Zenghui Yu <yuzenghui@huawei.com> wrote:

> It isn't clear what purpose the @bardirty serves. It might be used to avoid
> the unnecessary vfio_bar_fixup() invoking on a user-space BAR read, which
> is not required when bardirty is unset.
> 
> The variable was introduced in commit 89e1f7d4c66d ("vfio: Add PCI device
> driver") but never actually used, so it shouldn't be that important. Remove
> it.
> 
> Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
> ---
>  drivers/vfio/pci/vfio_pci_config.c  | 7 -------
>  drivers/vfio/pci/vfio_pci_private.h | 1 -
>  2 files changed, 8 deletions(-)

Yes, it seems to have been write-only all the time.

Reviewed-by: Cornelia Huck <cohuck@redhat.com>