2019-05-29 14:46:10

by Colin King

Subject: [PATCH][next] drm/i915: fix uninitialized variable 'subslice_mask'

From: Colin Ian King <[email protected]>

Currently subslice_mask is not initialized and so data is being
bit-wise or'd into a garbage value. Fix this by inintializing
subslice_mask to zero.

Addresses-Coverity: ("Uninitialized scalar variable")
Fixes: 1ac159e23c2c ("drm/i915: Expand subslice mask")
Signed-off-by: Colin Ian King <[email protected]>
---
drivers/gpu/drm/i915/intel_device_info.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_device_info.c b/drivers/gpu/drm/i915/intel_device_info.c
index 3625f777f3a3..d395a09b994f 100644
--- a/drivers/gpu/drm/i915/intel_device_info.c
+++ b/drivers/gpu/drm/i915/intel_device_info.c
@@ -298,7 +298,7 @@ static void cherryview_sseu_info_init(struct drm_i915_private *dev_priv)
{
struct sseu_dev_info *sseu = &RUNTIME_INFO(dev_priv)->sseu;
u32 fuse;
- u8 subslice_mask;
+ u8 subslice_mask = 0;

fuse = I915_READ(CHV_FUSE_GT);

--
2.20.1

2019-05-29 15:04:40

by Jani Nikula

Subject: Re: [PATCH][next] drm/i915: fix uninitialized variable 'subslice_mask'

On Wed, 29 May 2019, Colin King <[email protected]> wrote:
> From: Colin Ian King <[email protected]>
>
> Currently subslice_mask is not initialized and so data is being
> bit-wise or'd into a garbage value. Fix this by inintializing
> subslice_mask to zero.
>
> Addresses-Coverity: ("Uninitialized scalar variable")
> Fixes: 1ac159e23c2c ("drm/i915: Expand subslice mask")

This was already reverted for other reasons. Need to be fixed on the
next round. For future reference, please Cc: author and reviewers of the
referenced commit.

BR,
Jani.


> Signed-off-by: Colin Ian King <[email protected]>
> ---
> drivers/gpu/drm/i915/intel_device_info.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_device_info.c b/drivers/gpu/drm/i915/intel_device_info.c
> index 3625f777f3a3..d395a09b994f 100644
> --- a/drivers/gpu/drm/i915/intel_device_info.c
> +++ b/drivers/gpu/drm/i915/intel_device_info.c
> @@ -298,7 +298,7 @@ static void cherryview_sseu_info_init(struct drm_i915_private *dev_priv)
> {
> struct sseu_dev_info *sseu = &RUNTIME_INFO(dev_priv)->sseu;
> u32 fuse;
> - u8 subslice_mask;
> + u8 subslice_mask = 0;
>
> fuse = I915_READ(CHV_FUSE_GT);

--
Jani Nikula, Intel Open Source Graphics Center

2019-05-29 15:06:34

by Colin King

Subject: Re: [PATCH][next] drm/i915: fix uninitialized variable 'subslice_mask'

On 29/05/2019 16:04, Jani Nikula wrote:
> On Wed, 29 May 2019, Colin King <[email protected]> wrote:
>> From: Colin Ian King <[email protected]>
>>
>> Currently subslice_mask is not initialized and so data is being
>> bit-wise or'd into a garbage value. Fix this by inintializing
>> subslice_mask to zero.
>>
>> Addresses-Coverity: ("Uninitialized scalar variable")
>> Fixes: 1ac159e23c2c ("drm/i915: Expand subslice mask")
>
> This was already reverted for other reasons. Need to be fixed on the
> next round. For future reference, please Cc: author and reviewers of the
> referenced commit.

OK, will do.

Thanks, Colin
>
> BR,
> Jani.
>
>
>> Signed-off-by: Colin Ian King <[email protected]>
>> ---
>> drivers/gpu/drm/i915/intel_device_info.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_device_info.c b/drivers/gpu/drm/i915/intel_device_info.c
>> index 3625f777f3a3..d395a09b994f 100644
>> --- a/drivers/gpu/drm/i915/intel_device_info.c
>> +++ b/drivers/gpu/drm/i915/intel_device_info.c
>> @@ -298,7 +298,7 @@ static void cherryview_sseu_info_init(struct drm_i915_private *dev_priv)
>> {
>> struct sseu_dev_info *sseu = &RUNTIME_INFO(dev_priv)->sseu;
>> u32 fuse;
>> - u8 subslice_mask;
>> + u8 subslice_mask = 0;
>>
>> fuse = I915_READ(CHV_FUSE_GT);
>