Re: [PATCH] drm/tegra: submit: No need for Null pointer check before kfree

From: Mikko Perttunen
Date: Wed Dec 28 2022 - 07:29:37 EST


On 12/27/22 19:14, Deepak R Varma wrote:
kfree() & vfree() internally perform NULL check on the pointer handed
to it and take no action if it indeed is NULL. Hence there is no need
for a pre-check of the memory pointer before handing it to
kfree()/vfree().

Issue reported by ifnullfree.cocci Coccinelle semantic patch script.

Signed-off-by: Deepak R Varma <drv@xxxxxxxxx>
---
drivers/gpu/drm/tegra/submit.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/tegra/submit.c b/drivers/gpu/drm/tegra/submit.c
index 066f88564169..06f836db99d0 100644
--- a/drivers/gpu/drm/tegra/submit.c
+++ b/drivers/gpu/drm/tegra/submit.c
@@ -680,8 +680,8 @@ int tegra_drm_ioctl_channel_submit(struct drm_device *drm, void *data,
kfree(job_data->used_mappings);
}

- if (job_data)
- kfree(job_data);
+ kfree(job_data);
+
put_bo:
gather_bo_put(&bo->base);
unlock:
--
2.34.1




It continues to be the case that I think this transform is bad. Same applies to the host1x patch.

Mikko