Re: [PATCH][next] iommu/mediatek: Fix unsigned domid comparison with less than zero

From: Yong Wu
Date: Wed Feb 03 2021 - 20:12:21 EST


On Wed, 2021-02-03 at 13:59 +0000, Colin King wrote:
> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>
> Currently the check for domid < 0 is always false because domid
> is unsigned. Fix this by making it signed.
>
> Addresses-CoverityL ("Unsigned comparison against 0")
> Fixes: ab1d5281a62b ("iommu/mediatek: Add iova reserved function")
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>

Thanks for the fix.

Reviewed-by: Yong Wu <yong.wu@xxxxxxxxxxxx>

> ---
> drivers/iommu/mtk_iommu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
> index 0ad14a7604b1..823d719945b2 100644
> --- a/drivers/iommu/mtk_iommu.c
> +++ b/drivers/iommu/mtk_iommu.c
> @@ -640,7 +640,7 @@ static void mtk_iommu_get_resv_regions(struct device *dev,
> struct list_head *head)
> {
> struct mtk_iommu_data *data = dev_iommu_priv_get(dev);
> - unsigned int domid = mtk_iommu_get_domain_id(dev, data->plat_data), i;
> + int domid = mtk_iommu_get_domain_id(dev, data->plat_data), i;
> const struct mtk_iommu_iova_region *resv, *curdom;
> struct iommu_resv_region *region;
> int prot = IOMMU_WRITE | IOMMU_READ;