From 098336deb946f37a70afc0979af388b615c378bf Mon Sep 17 00:00:00 2001
From: Wen Yang <wen.yang99@zte.com.cn>
Date: Thu, 29 Nov 2018 14:01:50 +0800
Subject: drm/msm: Fix error return checking
Git-commit: 098336deb946f37a70afc0979af388b615c378bf
Patch-mainline: v4.20-rc6
References: bsc#1113956
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@zte.com.cn>
CC: Rob Clark <robdclark@gmail.com>
CC: David Airlie <airlied@linux.ie>
CC: Julia Lawall <julia.lawall@lip6.fr>
CC: linux-arm-msm@vger.kernel.org
CC: dri-devel@lists.freedesktop.org
CC: freedreno@lists.freedesktop.org
CC: linux-kernel@vger.kernel.org
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
---
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;
}
--
2.20.1