[PATCH v2] media: omap3isp: fix unbalanced dma_iommu_mapping

[Suman Anna]

Hi Mauro,

On 03/21/2018 05:26 AM, Laurent Pinchart wrote:
> Hi Suman,
> 
> Thank you for the patch.
> 
> On Wednesday, 14 March 2018 17:41:36 EET Suman Anna wrote:
>> The OMAP3 ISP driver manages its MMU mappings through the IOMMU-aware
>> ARM DMA backend. The current code creates a dma_iommu_mapping and
>> attaches this to the ISP device, but never detaches the mapping in
>> either the probe failure paths or the driver remove path resulting
>> in an unbalanced mapping refcount and a memory leak. Fix this properly.
>>
>> Reported-by: Pavel Machek <pavel at ucw.cz>
>> Signed-off-by: Suman Anna <s-anna at ti.com>
>> Acked-by: Sakari Ailus <sakari.ailus at linux.intel.com>
> 
> Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

I don't see this patch in -next yet, can you pick up this patch at your
earliest?

Thanks,
Suman

> 
>> ---
>> v2 Changes:
>>  - Dropped the error_attach label, and returned directly from the
>>    first error path (comments from Sakari)
>>  - Added Sakari's Acked-by
>> v1: https://patchwork.kernel.org/patch/10276759/
>>
>> Pavel,
>> I dropped your Tested-by from v2 since I modified the patch, can you
>> recheck the new patch again? Thanks.
>>
>> regards
>> Suman
>>
>>  drivers/media/platform/omap3isp/isp.c | 7 ++++---
>>  1 file changed, 4 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/media/platform/omap3isp/isp.c
>> b/drivers/media/platform/omap3isp/isp.c index 8eb000e3d8fd..f2db5128d786
>> 100644
>> --- a/drivers/media/platform/omap3isp/isp.c
>> +++ b/drivers/media/platform/omap3isp/isp.c
>> @@ -1945,6 +1945,7 @@ static int isp_initialize_modules(struct isp_device
>> *isp)
>>
>>  static void isp_detach_iommu(struct isp_device *isp)
>>  {
>> +	arm_iommu_detach_device(isp->dev);
>>  	arm_iommu_release_mapping(isp->mapping);
>>  	isp->mapping = NULL;
>>  }
>> @@ -1961,8 +1962,7 @@ static int isp_attach_iommu(struct isp_device *isp)
>>  	mapping = arm_iommu_create_mapping(&platform_bus_type, SZ_1G, SZ_2G);
>>  	if (IS_ERR(mapping)) {
>>  		dev_err(isp->dev, "failed to create ARM IOMMU mapping\n");
>> -		ret = PTR_ERR(mapping);
>> -		goto error;
>> +		return PTR_ERR(mapping);
>>  	}
>>
>>  	isp->mapping = mapping;
>> @@ -1977,7 +1977,8 @@ static int isp_attach_iommu(struct isp_device *isp)
>>  	return 0;
>>
>>  error:
>> -	isp_detach_iommu(isp);
>> +	arm_iommu_release_mapping(isp->mapping);
>> +	isp->mapping = NULL;
>>  	return ret;
>>  }
>