From: Wen Yang <wen.yang99@xxxxxxxxxx> [ Upstream commit 098336deb946f37a70afc0979af388b615c378bf ] The error checks on ret for a negative error return always fails because the return value of iommu_map_sg() is unsigned and can never be negative. Detected with Coccinelle: drivers/gpu/drm/msm/msm_iommu.c:69:9-12: WARNING: Unsigned expression compared with zero: ret < 0 Signed-off-by: Wen Yang <wen.yang99@xxxxxxxxxx> CC: Rob Clark <robdclark@xxxxxxxxx> CC: David Airlie <airlied@xxxxxxxx> CC: Julia Lawall <julia.lawall@xxxxxxx> CC: linux-arm-msm@xxxxxxxxxxxxxxx CC: dri-devel@xxxxxxxxxxxxxxxxxxxxx CC: freedreno@xxxxxxxxxxxxxxxxxxxxx CC: linux-kernel@xxxxxxxxxxxxxxx Signed-off-by: Sean Paul <seanpaul@xxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/msm/msm_iommu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/msm/msm_iommu.c b/drivers/gpu/drm/msm/msm_iommu.c index b23d33622f37..2a90aa4caec0 100644 --- a/drivers/gpu/drm/msm/msm_iommu.c +++ b/drivers/gpu/drm/msm/msm_iommu.c @@ -66,7 +66,7 @@ static int msm_iommu_map(struct msm_mmu *mmu, uint64_t iova, // pm_runtime_get_sync(mmu->dev); ret = iommu_map_sg(iommu->domain, iova, sgt->sgl, sgt->nents, prot); // pm_runtime_put_sync(mmu->dev); - WARN_ON(ret < 0); + WARN_ON(!ret); return (ret == len) ? 0 : -EINVAL; } -- 2.19.1
