[PATCH AUTOSEL 5.4 10/14] drm/msm/mdp5: check the return of kzalloc()

[PATCH AUTOSEL 5.4 10/14] drm/msm/mdp5: check the return of kzalloc()

[Sasha Levin]

From: Xiaoke Wang <xkernel.wang@foxmail.com>

[ Upstream commit 047ae665577776b7feb11bd4f81f46627cff95e7 ]

kzalloc() is a memory allocation function which can return NULL when
some internal memory errors happen. So it is better to check it to
prevent potential wrong memory access.

Besides, since mdp5_plane_reset() is void type, so we should better
set `plane-state` to NULL after releasing it.

Signed-off-by: Xiaoke Wang <xkernel.wang@foxmail.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/481055/
Link: https://lore.kernel.org/r/tencent_8E2A1C78140EE1784AB2FF4B2088CC0AB908@qq.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c b/drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c
index 83423092de2f..da0799333970 100644
--- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c
+++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c
@@ -179,7 +179,10 @@ static void mdp5_plane_reset(struct drm_plane *plane)
 		drm_framebuffer_put(plane->state->fb);
 
 	kfree(to_mdp5_plane_state(plane->state));
+	plane->state = NULL;
 	mdp5_state = kzalloc(sizeof(*mdp5_state), GFP_KERNEL);
+	if (!mdp5_state)
+		return;
 
 	/* assign default blend parameters */
 	mdp5_state->alpha = 255;
-- 
2.35.1

[PATCH AUTOSEL 5.4 11/14] drm/msm: Stop using iommu_present()

[Sasha Levin]

From: Robin Murphy <robin.murphy@arm.com>

[ Upstream commit e2a88eabb02410267519b838fb9b79f5206769be ]

Even if some IOMMU has registered itself on the platform "bus", that
doesn't necessarily mean it provides translation for the device we
care about. Replace iommu_present() with a more appropriate check.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Patchwork: https://patchwork.freedesktop.org/patch/480707/
Link: https://lore.kernel.org/r/5ab4f4574d7f3e042261da702d493ee40d003356.1649168268.git.robin.murphy@arm.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/msm/msm_drv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index 407b51cf6790..7322df9cf673 100644
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -303,7 +303,7 @@ bool msm_use_mmu(struct drm_device *dev)
 	struct msm_drm_private *priv = dev->dev_private;
 
 	/* a2xx comes with its own MMU */
-	return priv->is_a2xx || iommu_present(&platform_bus_type);
+	return priv->is_a2xx || device_iommu_mapped(dev->dev);
 }
 
 static int msm_init_vram(struct drm_device *dev)
-- 
2.35.1

Re: [PATCH AUTOSEL 5.4 11/14] drm/msm: Stop using iommu_present()

[Rob Clark]

You might want to drop this one, it seems to be causing some issues on
older generations.. I'll be sending another PR shortly with a revert.

https://patchwork.freedesktop.org/patch/482453

BR,
-R

On Tue, Apr 19, 2022 at 11:15 AM Sasha Levin <sashal@kernel.org> wrote:
>
> From: Robin Murphy <robin.murphy@arm.com>
>
> [ Upstream commit e2a88eabb02410267519b838fb9b79f5206769be ]
>
> Even if some IOMMU has registered itself on the platform "bus", that
> doesn't necessarily mean it provides translation for the device we
> care about. Replace iommu_present() with a more appropriate check.
>
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> Reviewed-by: Rob Clark <robdclark@gmail.com>
> Patchwork: https://patchwork.freedesktop.org/patch/480707/
> Link: https://lore.kernel.org/r/5ab4f4574d7f3e042261da702d493ee40d003356.1649168268.git.robin.murphy@arm.com
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> Signed-off-by: Rob Clark <robdclark@chromium.org>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
>  drivers/gpu/drm/msm/msm_drv.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
> index 407b51cf6790..7322df9cf673 100644
> --- a/drivers/gpu/drm/msm/msm_drv.c
> +++ b/drivers/gpu/drm/msm/msm_drv.c
> @@ -303,7 +303,7 @@ bool msm_use_mmu(struct drm_device *dev)
>         struct msm_drm_private *priv = dev->dev_private;
>
>         /* a2xx comes with its own MMU */
> -       return priv->is_a2xx || iommu_present(&platform_bus_type);
> +       return priv->is_a2xx || device_iommu_mapped(dev->dev);
>  }
>
>  static int msm_init_vram(struct drm_device *dev)
> --
> 2.35.1
>

Re: [PATCH AUTOSEL 5.4 11/14] drm/msm: Stop using iommu_present()

[Sasha Levin]

On Tue, Apr 19, 2022 at 11:53:23AM -0700, Rob Clark wrote:
>You might want to drop this one, it seems to be causing some issues on
>older generations.. I'll be sending another PR shortly with a revert.
>
>https://patchwork.freedesktop.org/patch/482453

Dropped, thanks!

-- 
Thanks,
Sasha