Re: [PATCH v2 09/10] iommu/vt-d: Avoid sending invalid page response

From: Auger Eric
Date: Mon Nov 18 2019 - 16:27:12 EST


Hi Jacob,

On 11/18/19 8:42 PM, Jacob Pan wrote:
> Page responses should only be sent when last page in group (LPIG) or
> private data is present in the page request. This patch avoids sending
> invalid descriptors.
>
> Fixes: 5d308fc1ecf53 ("iommu/vt-d: Add 256-bit invalidation descriptor
> support")
> Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
> Acked-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> ---
> drivers/iommu/intel-svm.c | 7 +++----
> 1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c
> index 26a2f57763ec..098c89246593 100644
> --- a/drivers/iommu/intel-svm.c
> +++ b/drivers/iommu/intel-svm.c
> @@ -688,11 +688,10 @@ static irqreturn_t prq_event_thread(int irq, void *d)
> if (req->priv_data_present)
> memcpy(&resp.qw2, req->priv_data,
> sizeof(req->priv_data));
> + resp.qw2 = 0;
> + resp.qw3 = 0;
> + qi_submit_sync(&resp, iommu);
OK so now all the qwords are initialized ;-)
> }
> - resp.qw2 = 0;
> - resp.qw3 = 0;
> - qi_submit_sync(&resp, iommu);
> -
> head = (head + sizeof(*req)) & PRQ_RING_MASK;
> }
>
>
Reviewed-by: Eric Auger <eric.auger@xxxxxxxxxx>

Thanks

Eric